MAXQ3180-RAN+ Maxim Integrated Products, MAXQ3180-RAN+ Datasheet
MAXQ3180-RAN+
Specifications of MAXQ3180-RAN+
Related parts for MAXQ3180-RAN+
MAXQ3180-RAN+ Summary of contents
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... Multifunction Electricity Meters Ordering Information PART TEMP RANGE MAXQ3180-RAN+ -40°C to +85°C + Denotes a lead(Pb)-free/RoHS-compliant package. Pin Configuration and Typical Application Circuit appear at end of data sheet. MAXQ is a registered trademark of Maxim Integrated Products, Inc. ...
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Low-Power, Multifunction, Polyphase AFE Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Low-Power, Multifunction, Polyphase AFE TABLE OF CONTENTS (continued) Global Interrupt Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Low-Power, Multifunction, Polyphase AFE TABLE OF CONTENTS (continued) Virtual Register Conversion Coefficients . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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... Overvoltage and Overcurrent Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63 Meter Units to Real Units Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63 Units Conversion Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 Calibration Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 Calibrating Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66 Calibrating Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66 Calibrating Phase Offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67 Interfacing the MAXQ3180 to External Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 Connections to the Power Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 Sensor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 Voltage Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 Voltage-Divider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 Voltage Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69 Current Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69 Current Shunt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69 Current Transformer ...
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Low-Power, Multifunction, Polyphase AFE TABLE OF CONTENTS (continued) Advanced Register Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Low-Power, Multifunction, Polyphase AFE TABLE OF CONTENTS (continued) Linearity Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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... Low-Power, Multifunction, Polyphase AFE TABLE OF CONTENTS (continued) Special Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98 Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98 Grounds and Bypassing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98 Specific Design Considerations for MAXQ3180-Based Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99 Additional Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99 Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99 Typical Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101 8 _______________________________________________________________________________________ ...
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... Figure 4a. SPI Interface Timing (CKPHA = .20 Figure 4b. SPI Interface Timing (CKPHA = .20 Figure 5. Read SPI Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24 Figure 6. Write SPI Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24 Figure 7. Flowchart for Reading from MAXQ3180 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 Figure 8. Flowchart for Writing to MAXQ3180 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 Figure 9. Per Sample Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56 Figure 10. Computation of RMS Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57 Figure 11. Phase Compensation for Energy Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58 Figure 12 ...
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Low-Power, Multifunction, Polyphase AFE ABSOLUTE MAXIMUM RATINGS Voltage Range on DVDD Relative to DGND .........-0.3V to +4.0V Voltage Range on AVDD Relative to AGND..........-0.3V to +4.0V Voltage Range on AGND Relative to DGND .........-0.3V to +0.3V Voltage Range on AVDD ...
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Low-Power, Multifunction, Polyphase AFE ELECTRICAL CHARACTERISTICS (continued 3.6V -40°C to +85°C, unless otherwise noted.) (Note 2) AVDD DVDD RST A PARAMETER SYMBOL Input Low Current RESET Pullup Resistance R Output High Voltage ...
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Low-Power, Multifunction, Polyphase AFE ELECTRICAL CHARACTERISTICS (continued 3.6V -40°C to +85°C, unless otherwise noted.) (Note 2) AVDD DVDD RST A PARAMETER SYMBOL SSEL Low to First SCLK Edge (Slave Enable) Last SCLK ...
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... HW MULTIPLY 48-BIT ACCUMULATE ______________________________________________________________________________________ REF ADC ADC CONTROL, ELECTRICITY METERING DSP, COMMUNICATIONS MANAGER WATCHDOG TIMER POR/ BROWNOUT SYSCLK MONITOR ADCCLK MAXQ3180 Block Diagram CFP, CFQ COUNTERS I/O BUFFERS I/O REGISTERS SPI I/O BUFFERS I/O REGISTERS I/O I/O REGISTERS BUFFERS HF RC OSC/8 ...
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... Master Out-Slave In Input. This line is used by the master to transmit data to the slave (the 15 MOSI MAXQ3180) over the SPI interface. Master In-Slave Out Output. This line is used by the MAXQ3180 (the slave) to transmit data back to 16 MISO the master over the SPI interface. ...
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... Precision Pulse Generators The MAXQ3180 includes two precision pulse genera- tors that generate a pulse whenever certain conditions are met. In the MAXQ3180, many meter quantities can be selected for conversion to meter pulses including absolute energy, net energy, reactive energy, voltage, and current. ...
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... INTERNAL RESET Figure 1. External Reset 16 ______________________________________________________________________________________ MAXQ3180, the SSEL line is normally driven low at the beginning of each SPI command. This means that if the master sends an SPI command after the MAXQ3180 enters Stop Mode, the MAXQ3180 automatically exits Stop Mode. There are several different sources that can cause the MAXQ3180 to undergo a reset cycle ...
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... Under normal circumstances, the MAXQ3180 always resets the watchdog timer often Power-On Reset enough to prevent it from expiring. However internal error of some kind causes the MAXQ3180 to lock up or power-fail RST enter an endless execution loop, the watchdog timer expires and triggers an automatic hardware reset. There ...
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... PWRF has been set hardware, it can only be cleared by the master ( system reset). Whenever PWRF = 1, if the EPWRF interrupt masking bit is also set to 1, the MAXQ3180 drives IRQ low to signal to the master that an interrupt condition (in this case, a power- fail warning) exists and requires attention. ...
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... SPI bus interface, is also used for master/slave communications because it allows the MAXQ3180 to notify the master that an interrupt condi- tion exists. Some SPI peripherals sacrifice speed in favor of simulating a half-duplex operation. This is not the case with the MAXQ3180 truly a full-duplex SPI slave. 19 ...
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... Transfers over the SPI interface always start with the most significant bit and end with the least significant bit. All SPI data transfers to and from the MAXQ3180 are always 8 bits (one byte) in length. The MAXQ3180 SPI interface does not support 16-bit character lengths. ...
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... MAXQ3180’s clock frequency divided by 4. For example, when the MAXQ3180 is run- ning at 8MHz, the SPI clock frequency must be 2MHz or less. And if the MAXQ3180 is running in LOWPM Mode (or if the crystal is still warming up), the SPI clock frequency must remain at 250kHz or less for proper communications operation ...
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... For this reason, the MAXQ3180 always sends zero or more bytes of a NAK character (0x4E or ASCII ‘N’) followed by an ACK char- acter (0x41, or ASCII ‘A’) before sending the data. ...
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... mitted CRC byte does not match the calculated CRC byte (for a write command), the MAXQ3180 ignores the command. The length of the transfer is defined by the first com- mand byte and the status of the CRCEN bit in the OPMODE1 register ...
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... DSPRDY bit, otherwise, host soft- ware is not able to detect the completion of the new DSP cycle. The MAXQ3180 does not clear the bit; it only sets the bit whenever a DSP cycle processing is completed. Users can clear the bit directly after the confirmation that the bit is set ...
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... GET 0x4E? GET 0x41? SEND 0x00 DONE? EXIT Figure 8. Flowchart for Writing to MAXQ3180 Register Set The virtual registers contain calculated values derived from one or more real registers. They are calculated at the time they are requested, and thus can involve addi- tional time to return a value. Most virtual registers are 8 bytes in length and are delivered least significant byte first ...
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Low-Power, Multifunction, Polyphase AFE Table 3. RAM Register Map x0h x1h x2h x3h 0x00 STATUS MODE0 MODE1 MODE2 0x01 AUX_CFG SYS_KHZ 0x02 PLS1_WD THR1 0x03 AVG_C HPF_C 0x04 NS R_ 0x05 R_ADCACQ SPICF 0x06 CHKSUM LINEFR 0x11 ...
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Low-Power, Multifunction, Polyphase AFE Table 4. Virtual Register Map x0 x1 0x80 PWRP.A 0x81 PWRQ.A 0x82 PWRS.A 0x83 V.HARM V.A 0x84 I.N, I.HARM I.A 0x85 HARM_NF 0x86 0x87 ENRS.A 0x88 PWRPF.A 0x89 PWRQF.A 0x8A PWRSF.A 0x8B ENRSF.A 0x8C ENRP.A 0x8D ...
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... BIT NAME 7, 3 — Reserved. When set, the high-frequency crystal has failed and the MAXQ3180 is operating from its internal ring 6 CROFF oscillator. Under these circumstances, energy accumulation is not accurate and the SPI bus does not operate at full speed. When set, the last reset was due to power-on-reset. Host should clear this bit to allow the next POR ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: — — Reset BIT NAME 7:5, 0 — Reserved. When set, the high-frequency crystal oscillator is disabled and the XTAL1 pin is configured EXTCLK clock input ...
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... ______________________________________________________________________________________ Operating Mode Register 1 (OPMODE1) (0x002) (continued) FUNCTION Use this configuration when the load is connected in a wye arrangement and neutral is connected to MAXQ3180 ground, or when the load is connected in a delta arrangement and isolated voltage and current sensors are used. This C arrangement measures power in each load branch rather than power in each source branch ...
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... Setting this bit disables all fundamental frequency registers 4 DFUN but allows the MAXQ3180 to calculate other parameters at a higher rate. Set this bit when (1) fundamental mode values do not need to be read, and (2) R_ADCRATE needs to be reduced below its default value. ...
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Low-Power, Multifunction, Polyphase AFE BIT NAME 3P4W Wiring (00) 3V3A (10) 2:1 WIRSYS 1P3W (00) Selects the mechanism to use for calculating apparent power APPSEL RMS ...
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... When set, the direction of real energy flow has changed (that is, from toward the load to away from the 12 DCHA load, or from away from the load to toward the load). When set, the MAXQ3180 has failed to detect zero crossings on one or more voltage channels for the 11 NOZX time defined by the NZX_TIMO register. ...
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... EDCHA been observed to have changed (that is, from toward the load to away from the load, or from away from the load to toward the load). When set, this flag causes the IRQ pin to become active when the MAXQ3180 has failed to detect zero 11 ENOZX crossings on one or more voltage channels for at least one DSP cycle. ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: This register selects which phases are included in the CFP pulse output and also selects which quantity is accumu- lated to drive the pulse output. BIT NAME CFP Pulse Output Source ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: This register selects which phases are included in the CFQ pulse output and also selects which quantity is accumu- lated to drive the pulse output. BIT NAME CFQ Pulse Output Source ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: Bit Name: Reset: Bit Name: Reset: This register designates the threshold of the CFP pulse. This value is used to set the ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: Bit Name: Reset: Bit Name: Reset: This register designates the threshold of the CFQ pulse. This value is used to set the ...
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Low-Power, Multifunction, Polyphase AFE Voltage Gain, Phase X = A/B/C (X.V_GAIN) (A: 0x132, B: 0x21E, C: 0x30A) Bit Name: Reset: Bit Name: Reset: This register contains gain coefficient for phase X voltage channel. The raw values ...
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Low-Power, Multifunction, Polyphase AFE Phase-Angle Compensation, Medium Range, Phase X = A/B/C (X.PA1) Bit Name: Reset: Bit Name: Reset: This signed register contains the angle fraction of one radian, to add to the measured ...
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... Name: Reset: This register specifies the fraction of full-scale current below which a no-load condition is declared. When X.IRMS falls below this level, the MAXQ3180 no longer accumulates power for phase X. Full scale is represented by 0x10000. The maximum value for this register is 0xFFFF. ______________________________________________________________________________________ Overvoltage Level (OVLVL) (0x046) ...
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Low-Power, Multifunction, Polyphase AFE Interrupt Flags, Phase X = A/B/C (X.FLAGS) (A: 0x144, B: 0x230, C: 0x31C) Bit Name: — — Reset The X.FLAGS register contains condition flags that relate to the function of phase X ...
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Low-Power, Multifunction, Polyphase AFE Interrupt Mask, Phase X = A/B/C (X.MASK) (A: 0x145, B: 0x231, C: 0x31D) Bit Name: DIR_R DIR_A Reset BIT NAME Reactive Energy Direction Status 7 DIR_R 0 = positive 1 = negative ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: Line frequency, LSB = 0.001Hz. Power Factor, Phase X = A/B/C (X.PF) (A: 0x1C6, B: 0x2B2, C: 0x39E) Bit Name: Reset: Bit ...
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Low-Power, Multifunction, Polyphase AFE RMS Current, Phase X = A/B/C (X.IRMS) (A: 0x1CC, B: 0x2B8, C: 0x3A4) Bit Name: Bit Name: Bit Name: Bit Name: This register provides the raw RMS current ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Bit Name: Bit Name: Bit Name: On every DSP cycle, the contents of the X.ACT register are tested, and, if negative, absolute values are added to ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Bit Name: Bit Name: Bit Name: On every DSP cycle, the contents of the X.REA register are tested, and, if negative, absolute values are added to ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: This register contains the value by which the raw voltage value in each phase (A.VRMS, B.VRMS, and C.VRMS) is multiplied before being presented to the virtual ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: This register contains the value by which the raw power value in each phase is multiplied before being presented to the virtual power registers. The table ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: This register contains the value by which the raw accumulated energy value in each phase is multiplied before being presented to the virtual energy registers. The ...
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Low-Power, Multifunction, Polyphase AFE Energy Units Conversion Coefficient (ENR_CC) (0x01A) (continued) DESCRIPTION Reactive energy, phase C, positive direction, fundamental only Reactive energy, phase C, reverse direction, fundamental only Reactive energy, total, fundamental only Apparent energy, phase A, fundamental only Apparent ...
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Low-Power, Multifunction, Polyphase AFE Reactive Power, Phase X = A/B/C/T (PWRQ.X) (A: 0x811, B: 0x812, C: 0x814, T: 0x817) This signed register contains the reactive instantaneous power delivered into phase A/B/C or total. Power is calculat- ed from the instantaneous ...
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Low-Power, Multifunction, Polyphase AFE RMS Volts, Phase X = A/B/C (V.X) (A: 0x831, B: 0x832, C: 0x834) This register contains the RMS voltage on phase A/B/C. The units are defined by the VOLT_CC setting such that V.X = X.VRMS x ...
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Low-Power, Multifunction, Polyphase AFE Real Energy, Phase A/B/C/T (ENRP.X) (A: 0x8C1, B: 0x8C2, C: 0x8C4, T: 0x8C7) This signed register contains the real accumulated energy delivered into phase A/B/C or total. The register is calcu- lated according to the following ...
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... C CLK Using the default register settings (R_ADCRATE = 13Fh = 319d), the time for each analog slot measurement ( 40μs when the MAXQ3180 is running at 8MHz. C Since there are eight analog scan slots in the measure- ment frame, the total time for all measurements ( Using the default settings with the MAXQ3180 ...
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... NS (and every other value in the meter, since they depend on NS) would have a significant amount of uncertainty. A better method is to use each newly cal- culated value input to a filter. The output of the filter is then the value of NS that is actually used in calculations. In the MAXQ3180, this filter is controlled by the AVG_NS register I_GAIN ...
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Low-Power, Multifunction, Polyphase AFE A second problem with updating NS on every line cycles is the fact that noise impulses that occur at near- ly the same time as the zero crossing can shift the zero crossing, affecting the accuracy ...
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... Consequently, for the most precise mea- surements, the phase between the voltage and current signals must be compensated. In the MAXQ3180, the energy signals are compensated for phase offset by performing a complex multiplication of the signal with the contents of the appropriate phase offset register ...
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... If no ascending zero crossings are detected within a specified number (NZX_TIMO) of analog scan sample periods, the NOZXF (X.FLAGS) flag is set by the MAXQ3180 to noti- fy the master of this condition. If the NOZXM bit is set, this flag sets the NOZX bit in the IRQ_FLAG. If the inter- ...
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... So far in this discussion, the values being calculated and managed in the MAXQ3180 have been based on fundamental units meaningful to the device itself: volt- age as a binary fraction of full-scale voltage; current as a binary fraction of full-scale current, and time as a non- integer multiple of the ADC frame time. ...
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... The MAXQ3180 measures energy. But power is just energy per unit time, and the MAXQ3180 keeps track of the time unit over which energy is accumulated. This is simply the NS value, the fractional number of samples that comprises one DSP cycle. So converting energy to power is as simple as dividing the accumulated energy over one DSP cycle by NS ...
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... PHASEA, PHASEB, and PHASEC bits in the PLSCFG1 or PLSCFG2 registers to include them in the accumulation. Generating Pulses On every DSP cycle, the MAXQ3180 adds the value in the selected register (or set of registers) to the pulse accumulator. If the value in the pulse accumulator exceeds the value in the associated threshold register ...
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... OCLVL register. Both OVLVL and OCLVL registers represent the bits 23:8 of the VRMS or IRMS registers. Any time the MAXQ3180 detects the RMS-value exceeding a thresh- old level, the interrupt flag is set. If enabled, any of these flags issues an interrupt request. All inter- rupt flags are “ ...
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... Meter units are defined with respect to the base para- TR meters as shown in Table 5. is design TR When reading virtual registers, the MAXQ3180 uses the configurable conversion coefficients AMP_CC, VOLT_CC, PWR_CC, and ENR_CC to return meaningful data. Table 6 describes how to set the coefficients. and ADC full-scale ...
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... I Use the default ADC timing t = 320μs, we get the fol- FR lowing meter unit to physical unit conversion coeffi- cients (these coefficients are not part of the MAXQ3180 registers): 24 MU_AMP = 6.1E-6 (A) FS ...
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... FS • Divide the applied value (in meter unit) by the value read from the MAXQ3180. The result should be a value between 0 and 2. If the value falls outside of this range, you have probably miscalculated V • Multiply the calculated value by 2 gain value to be programmed into A.V_GAIN. Ensure the most significant bit is 0 ...
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... Low-Power, Multifunction, Polyphase AFE • Divide the applied value (in meter unit) by the value read from the MAXQ3180. The result should be a value between 0 and 2. If the value falls outside of this range, you have probably miscalculated I • Multiply the calculated value by 2 gain value to be programmed into A.I_GAIN. Ensure the most significant bit is 0 ...
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... The MAXQ3180 supports all of these connection arrangements. Sensor Selection The MAXQ3180 supports a variety of voltage and cur- rent sense elements. This section describes the proper- ties of many of these sensing devices. A voltage-divider is an ideal voltage-sensing element when there is no need for voltage isolation ...
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... There are several other registers that directly affect the AFE function. These registers directly affect the hard- ware functionality, and should be modified only when it is explicitly required. For example, if the MAXQ3180 is operated at some frequency other than the nominal 8MHz system clock, modification of these registers by supervisory code becomes necessary to maintain a 320μ ...
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... LPF using following formula: ZC LPF The MSB of this register must be zero. For each phase A, B, and C, the MAXQ3180 counts the number of scan frames (NS) between zero crossings within a DSP cycle. Each individual phase zero-crossing event contributes the raw NS count that plugs as input to lowpass filter (AVG_NS/65,536 ...
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... Also in the AUX_CFG register are two bits that enable the auxiliary channel and enable harmonic measure- ment on the auxiliary channel. To enable the auxiliary channel, set the ENAUX bit. Once set, the MAXQ3180 will perform an RMS calculation on the selected chan- nel. This is useful only for the I ...
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... I . Divide the results of this cal- FS culation by the value read from the MAXQ3180. The result should be a value between 0 and 2. Convert the 14 integer by multiplying 2 , and ensure MSB is zero. The result is the gain value to be programmed into A ...
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... These registers configure the time slot normally assigned to current channels A/B/C. We recommend leaving these registers at their default values. If they must be reassigned, one must ensure that all the current and voltage chan- nels are reassigned properly so that the MAXQ3180 computes the power/energy parameters as intended by your setup. ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset A: Reset B: Reset C: These registers configure the time slot normally assigned to voltage channels A/B/C. The user may wish to change the PGG settings to match the voltage sensor. ...
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Low-Power, Multifunction, Polyphase AFE Time Slot Assignment—Neutral Current Channel (SCAN_IN) (0x00E) Bit Name: Reset: This register configures the time slot normally assigned to the neutral current channel. The user can change the DADCNV bit to enable/disable neutral current ...
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Low-Power, Multifunction, Polyphase AFE Time Slot Assignment—Temperature Channel (SCAN_TE) (0x00F) Bit Name: Reset: This register configures the time slot normally assigned to the temperature measurement device. This register is managed by the firmware and should not be modified ...
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... Name: ENHARM ENAUX Reset The MAXQ3180 can monitor the RMS value of one auxiliary channel in addition to its normal processing. The Auxiliary Channel Configuration register selects which input the auxiliary channel processes and what processing is applied to the auxiliary channel. BIT NAME 15:13, 5:3 — ...
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... The NS register defines the fundamental timing for the electricity meter. It defines a DSP cycle in terms the period of the ADC scan frame. Generally, this register is calculated and updated automatically by the MAXQ3180 firmware based on the zero-crossing detection, and whether noise rejection (REJ_NS) and averaging (AVG_NS) are enabled. ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: This register establishes the sensitivity of the NS rejection filter setting measure of the line frequency line cycle occurs that is ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: This register determines whether the all other measured values in the electricity meter are averaged over time. If the value of this register is nonzero, all ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: This register specifies the b (feed-forward) coefficient for the fundamental-mode filter using the following formula: 0 The MSB of this register must be zero. Bit: 31 ...
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Low-Power, Multifunction, Polyphase AFE Bit Name: Reset: Bit Name: Reset: This register specifies the b (feed-forward) coefficient for the harmonic-mode filter using the following formula: 0 The MSB of this register must be zero. Bit: 31 ...
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... ADCASD ADCRY Reset This register is a mirror of a CPU register in the MAXQ3180. This register should not be modified by supervisory code. BIT NAME Disable ADC Automatic Shutdown. Normally, the ADC analog section is powered off following a conversion to conserve power. If this bit is set, the ADC leaves the analog section powered on ...
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... Name: ESPII SAS Reset This register is a mirror of a CPU register in the MAXQ3180. This register configures the SPI port of the MAXQ3180. BIT NAME 7 ESPII Enable SPI Interrupt. If set, arrival of a character on the SPI bus causes a CPU interrupt. SPI Slave Select Polarity. If clear, SSEL is assumed to be active low; if set, SSEL is assumed to be ...
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... Name: Reset: This register specifies the time in DSP cycles that the MAXQ3180 waits before accumulating energy. If this register is nonzero decremented on each DSP cycle. If the result of the decrement is nonzero, the results of the DSP cycle are discarded and are not accumulated to the energy registers. This register is useful for delaying the initiation of energy accumulation on startup or after some hardware function has been modified ...
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... Reset: Bit Name: Reset: This register specifies the fraction of full-scale current that causes the MAXQ3180 to switch from PA1 to PA2 to pro- vide phase-angle compensation. For more information, see the PA0, PA1, and PA2 register descriptions. The full- scale current is represented by 0x10000. Bit ...
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Low-Power, Multifunction, Polyphase AFE Gain, Fundamental Energy, Phase X = A/B/C (X.EF_GAIN) (A: 0x136, B: 0x222, C: 0x30E) Bit Name: Reset: Bit Name: Reset: This register contains gain coefficient for phase X fundamental energy. The raw ...
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Low-Power, Multifunction, Polyphase AFE Linearity Offset, Low Range, Phase X = A/B/C (X.OFFS_LO) (A: 0x13C, B: 0x228, C: 0x314) Bit Name: Reset: Bit Name: Reset: This signed register contains the linearity offset for phase X current ...
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Low-Power, Multifunction, Polyphase AFE Fundamental Energy Overflow Flags, Phase X = A/B/C (X.EFOVER) Bit Name: — — Reset These bits indicate an overflow condition has occurred on a fundamental frequency energy accumulator. An over- flow condition ...
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Low-Power, Multifunction, Polyphase AFE Energy, Fundamental, Real Negative, Phase X = A/B/C (X.EAFNEG) Bit Name: Bit Name: Bit Name: Bit Name: On every DSP cycle, the contents of the X.ACTF register are ...
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... On every DSP cycle, the contents of the X.ESF register are added to this register. When this register overflows, the SFOV bit in the X.EFOVER register is set. When the MAXQ3180 is operating in low-power mode, energy is not accu- mulated. However, during low-power mode, current values are accumulated to this register, making this register accumulate ampere-hours ...
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Low-Power, Multifunction, Polyphase AFE Real Energy, Phase X = A/B/C (X.ACT) (A: 0x1D0, B: 0x2BC, C: 0x3A8) Bit Name: Bit Name: Bit Name: Bit Name: This signed register provides the raw real ...
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Low-Power, Multifunction, Polyphase AFE Apparent Energy, Phase X = A/B/C (X.APP) (A: 0x1D8, B: 0x2C4, C: 0x3B0) Bit Name: Bit Name: Bit Name: Bit Name: This signed register provides the raw apparent ...
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Low-Power, Multifunction, Polyphase AFE Fundamental Reactive Energy, Phase X = A/B/C (X.REAF) (A: 0x1E0, B: 0x2CC, C: 0x3B8) Bit Name: Bit Name: Bit Name: Bit Name: This signed register accumulates energy in ...
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... This register contains the calculated 16-bit arithmetic checksum over critical configuration and calibration registers updated on every DSP cycle. In use, the administrative processor records the value in the CHKSUM register and then checks it periodically to verify that no configuration or calibration registers have changed. The MAXQ3180 sets the CHSCH bit when this register’s value changes. ...
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Low-Power, Multifunction, Polyphase AFE This signed register contains the real instantaneous power delivered into phase A/B/C or total at the fundamental line frequency only. Power is calculated from the instantaneous energy measurement according to the following equation: Byte 7 (MSByte ...
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Low-Power, Multifunction, Polyphase AFE This register contains the instantaneous apparent power delivered into phase A/B/C or total at the fundamental line frequency only. Power is calculated from the instantaneous energy measurement according to the following equation: Byte 7 (MSByte unused) ...
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... The MAXQ3180 must have separate ground areas for the analog (AGND) and digital (DGND) portions, con- nected together at a single point. ...
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... Doing so reduces the susceptibility of the design to fast transient noise. Because the MAXQ3180 is designed for use in systems where high voltages are present, care must be taken to route all signal paths, both analog and digital, as far away as possible from the high-voltage components ...
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... Low-Power, Multifunction, Polyphase AFE 100 _____________________________________________________________________________________ VOLTAGE SENSE R1 V0P R2 R1 V1P R2 R1 V2P R2 VCOMM VN CURRENT TRANSFORMER I0P R3 R3 I0N I1P R3 R3 I1N I2P R3 R3 I2N Typical Application Circuit MAXQ3180 MASTER ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ___________________ 101 © 2009 Maxim Integrated Products DESCRIPTION V ...