isl12020m Intersil Corporation, isl12020m Datasheet

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... SRAM and Integrated ppm Temperature ± Compensation and Auto Daylight Saving The ISL12020M device is a low power real time clock (RTC) with an embedded temperature sensor for oscillator compensation, clock/calendar, power fail, low battery monitor, brownout indicator, single periodic or polled alarms, intelligent battery-backup switching, and 128 bytes of battery-backed user SRAM ...

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... The output is open drain and requires a pull-up resistor Power supply. DD 16, 17, 18, X1 Crystal Connection. The X1 pin is the input of an inverting amplifier and is connected to one pin of an internal 19, 20 32.768kHz quartz crystal. Do not connect in an application circuit, floating electrical connection. 2 ISL12020M V RANGE TEMP RANGE DD (V) 2.7 to 5.5 - ...

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... The X1 and X2 pins are connected internally to a crystal and should be a floating electrical connection. 4. The ISL12020M Oscillator Initial Accuracy can change after solder reflow attachment. The amount of change will depend on the reflow temperature and length of exposure. A general rule is to use only one reflow cycle and keep the temperature and time as short as possible. ...

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... START Condition Hold Time HD:STA t Input Data Setup Time SU:DAT t Input Data Hold Time HD:DAT t STOP Condition Setup Time SU:STO 4 ISL12020M = +2.7 to +5.5V, Temperature = -40°C to +85°C, unless otherwise stated. DD CONDITIONS =+2.7 to +5.5V, Temperature = -40°C to +85°C, unless otherwise specified. DD TEST CONDITIONS 3mA +25° ...

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... C specific parameters and are not tested, however, they are used to set conditions for testing devices to validate specification. 12. Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified. Temperature limits established by characterization and are not production tested. 5 ISL12020M =+2.7 to +5.5V, Temperature = -40°C to +85°C, unless otherwise specified. (Continued) DD TEST CONDITIONS (Note 12) From SDA rising edge to SCL falling edge ...

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... FIGURE 1. STANDARD OUTPUT LOAD FOR TESTING THE DEVICE WITH V = 5.0V DD Symbol Table WAVEFORM INPUTS Must be steady May change from LOW to HIGH May change from HIGH to LOW Don’t Care: Changes Allowed N/A 6 ISL12020M t t HIGH LOW t SU:DAT t HD:DAT = 5V DD FOR V = 0.4V OL AND I = 3mA OL OUTPUTS ...

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... TEMPERATURE (°C) FIGURE TEMPERATURE DD1 5. 3. -40 - TEMPERATURE (°C) FIGURE 6. OSCILLATOR ERROR vs TEMPERATURE 7 ISL12020M Temperature is +25°C unless otherwise specified. 1600 1400 1200 1000 4.3 4.8 5.3 BAT = 2. 2. 5.5V BAT V = 3.0V BAT 800 ...

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... FIGURE 10. I with TSE = 1 vs TEMPERATURE DD General Description The ISL12020M device is a low power real time clock (RTC) with embedded temperature sensor and crystal. It contains crystal frequency compensation circuitry over the operating temperature range good to ±5ppm accuracy. It also contains a clock/calendar with Daylight Savings Time (DST) ...

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... Many types of batteries can be used with Intersil RTC products. For example, 3.0V or 3.6V Lithium batteries are appropriate, and battery sizes are available that can power the ISL12020M for years. Another option is to use a Super Capacitor for applications where V for month. See the “Application Section” on page 25 for more information ...

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... C bus is deactivated in battery-backup mode to reduce power consumption. Aside from this, all RTC functions are operational during battery-backup mode. Except for SCL and SDA, all the inputs and outputs of the ISL12020M are active during battery-backup mode unless disabled via the control register. ...

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... The frequency output can be enabled/disabled during battery-backup mode using the FOBATB bit. General Purpose User SRAM The ISL12020M provides 128 bytes of user SRAM. The SRAM will continue to operate in battery-backup mode. However, it should be noted that the I battery-backup mode. ...

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... VHR VMIL TSV2B 19h VDT 0 1Ah VMO 0 1Bh BSC 0 1Ch BMN 0 1Dh BHR BMIL TSB2V 1Eh BDT 0 1Fh BMO 0 12 ISL12020M BIT SC22 SC21 SC20 SC13 MN22 MN21 MN20 MN13 0 HR21 HR20 HR13 0 DT21 DT20 DT13 0 0 MO20 MO13 ...

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... NPPM 2Bh NPPMH 0 2Ch XT0 D XT0 2Dh ALPHAH D ALPHAH 2Eh GPM1 GPM17 GPM 2Fh GPM2 GPM27 13 ISL12020M BIT DstMoFd20 DstMoFd13 DstMoFd12 DstMoFd11 DstMoFd10 DstDwFdE DstWkFd12 DstWkFd11 DstWkFd10 DstDwFd12 DstDwFd11 DstDwFd10 D DstDtFd21 DstDtFd20 DstDtFd13 D DstHrFd21 DstHrFd20 DstHrFd13 D D XDstMoRv2 ...

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... This means that the year 2000 is a leap year and the year 2100 is not. The ISL12020M does not correct for the leap year in the year 2100. Control and Status Registers (CSR) Addresses [07h to 0Fh] ...

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... FREQUENCY OUT CONTROL BITS (FO<3:0>) These bits enable/disable the frequency output function and select the output frequency at the IRQ/F for frequency selection. Default for the ISL12020M is FO<3:0> = 1h, or 32.768kHz output (F 15 ISL12020M frequency mode is enabled, it will override the alarm mode at the IRQ/F TABLE 5 ...

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... See Table 10. The IDTR0 register should only be changed while the TSE (Temp Sense Enable) bit is “0”. 2.550 2.805 The ISL12020M has a preset Initial Digital Trimming value corresponding to the crystal in the module. This value is 3.060 recalled on initial power-up and should never be changed for 4 ...

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... This enables fine frequency adjustment for trimming initial crystal accuracy error or to correct for aging drift. The ISL12020M has a preset Initial Analog Trimming value corresponding to the crystal in the module. This value is recalled on initial power-up and should never be ...

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... The practical range of Actual ALPHA values is from -0.020 to -0.060. The ISL12020M has a preset ALPHA value corresponding to the crystal in the module. This value is recalled on initial power-up and should remain unchanged for best compensation performance, although the user can override this preset value if so desired ...

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... The ISL12020M has a preset BETA value corresponding to the crystal in the module. This value is recalled on initial power-up and should never be changed for best temperature compensation performance, although the user may override this preset value if so desired. The value for BETA should only be changed while the TSE (Temp Sense Enable) bit is “ ...

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... ALM bit in the status register to “1” and also bringing the IRQ/F low. 20 ISL12020M Example 2 • Pulsed interrupt once per minute (IM = ”1”) • Interrupts at one minute intervals when the seconds register seconds. ...

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... Week of the month and the Day of the Week. DstDwFdE sets the priority of the Day/Week over the Date. For DstDwFdE = 1, Day/Week is the priority. You must have the correct Day of 21 ISL12020M TABLE 20. DST FORWARD REGISTERS ...

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... XT0. Crystals normally have a turnover temperature between +20°C and +30°C, with most (EQ. 4) occurring near +25°C. ADDR 2Ch The ISL12020M has a preset turnover temperature corresponding to the crystal in the module. This value recalled on initial power-up and should never be changed for best temperature compensation performance, although the user may override this preset value if so desired ...

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... Data states on the SDA line can change only during SCL LOW periods. SDA state changes during SCL HIGH are reserved for indicating START and STOP conditions (see Figure 15). On power-up of the ISL12020M, the SDA pin is in the input mode. TABLE 25. ALPHA HOT REGISTER ...

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... K receiver pulls the SDA line LOW to acknowledge the reception of the eight bits of data (see Figure 16). The ISL12020M responds with an ACK after recognition of a START condition followed by a valid Identification Byte, and once again, after successful receipt of an Address Byte. The ISL12020M also responds with an ACK after receiving a Data Byte of a write operation ...

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... A Write operation requires a START condition, followed by a valid Identification Byte, a valid Address Byte, a Data Byte, and a STOP condition. After each of the three bytes, the ISL12020M responds with an ACK. At this time, the I interface enters a standby state. Read Operation A Read operation consists of a three byte instruction, followed by one or more Data Bytes (see Figure 19) ...

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... IRQ/F OUT from the RTC device as well. Measuring Oscillator Accuracy The best way to analyze the ISL12020M frequency accuracy is to set the IRQ/F at the output of that pin on a high accuracy frequency counter (at least 7 digits accuracy). Note that the IRQ drain output and will require a pull-up resistor. ...

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... Temperature Compensation Operation The ISL12020M temperature compensation feature needs to be enabled by the user. This must be done in a specific order as follows. 1. Read register 0Dh, the BETA register. This register contains the 5-bit BETA trimmed value, which is automatically loaded on initial power-up. Mask off the 5LSB’ ...

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... Package Outline Drawing L20.4.0x5.5 20 LEAD DUAL FLAT NO-LEAD PLASTIC PACKAGE Rev 2, 6/08 4.00 PIN 1 INDEX AREA TOP VIEW (4.95) (2X 0.20) (4.50 ) 10X 0.50 10X 0.50 10X 0. 0.25 Package Boundary 2X 1.50 10X 0.25 0.30 2X 2.44 (4.85) (4.95) TYPICAL RECOMMENDED LAND PATTERN 28 ISL12020M 0.300 0.50 4 2.20 0.10 2X 18X 0.50 0. MAX. 1.30 10X 0.70 (4.40) (2.20) (3.0) (0.10) 2.10 NOTES: 1. Dimensions are in millimeters. ...