DS2790 Maxim Integrated Products, DS2790 Datasheet
DS2790
Related parts for DS2790
DS2790 Summary of contents
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... GENERAL DESCRIPTION The DS2790 provides a complete fuel gauging and protection solution for single cell Li-Ion battery packs. A low-power 16-bit MAXQ20 microcontroller with generous program and data memory, combined with an accurate measurement system for battery current, voltage, and temperature provide the ideal platform for customized fuelgauge algorithms ...
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... SCL, SDA, P0.0–P0.5 Output Logic Low: P0.4–P0.5 Output Logic High: SCL, SDA Pulldown Current SCL, SDA Pullup Current P0.0–P0.3 Pullup Current 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector SYMBOL CONDITIONS CPU Mode I CPU (Note 1, 2) ANALOG Mode I ANALOG ...
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... DD A PARAMETER Output Low: CC Output Low: DC Output High: CC Output High: DC Output Resistance: CC, DC Output Voltage: CP Overvoltage Detect Charge Enable 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector SYMBOL CONDITIONS Rising and Falling t PR Edges V V IS1– IS2 I LSB ...
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... Data Hold Time Data Setup Time Rise Time of both SDA and SCL Signals Fall Time of both SDA and SCL Signals 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector SYMBOL CONDITIONS UVF = 10111b (Note 3) COCT = DOCT = 00b COCT = DOCT = 01b ...
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... Note 12 the cumulative time the slave is allowed to extend the clock from the initial START to the STOP. If the DS2790 LOW:SEXT exceeds this time, it will release both SDA and SCL and reset the communication interface. Note 13 the cumulative time the master is allowed to extend the clock cycles within each byte of a communication sequence ...
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... Figure 1. 2-Wire Bus Timing Diagram SDA LOW SCL t HD;STA S Figure 2. JTAG Timing Diagram TCK TMS / TDI TDO 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector SU;DAT SU;STA HD;DAT Sr V REF DVTH THDX ...
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... IN 27 N.C. 28 N.C. PAD 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector DESCRIPTION No Connection No Connection Charge Pump Output. Bypass Pack Plus. Positive pack terminal connection. Discharge Control. Discharge FET gate drive output. Charge Control. Charge FET gate drive output. 2-wire Serial Interface Clock Input and Output 2-wire Serial Interface Data Input and Output Programmable I/O Pin ...
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... PLS & CONTROL VDD CC FET DRIVERS DC CP FET CHARGE VDD PUMP VDD_INT VSS VSS_INT 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector VOLTAGE (VIN - AVSS) A/D CONTROL TEMPERATURE ANALOG REGISTERS BOI, VI, CI, TI TCI SCI, SDI INTERFACE SNDI BOOTLOADER INTERRUPT ...
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... DETAILED DESCRIPTION The following is an introduction to the primary features of the DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector. More detailed descriptions of the device features can be found in the errata sheets, and user's guides described later in the Additional Documentation section. DS2790 Overview The DS2790 incorporates the 16-bit MAXQ20 microcontroller core with 16 accumulators and 16-level hardware stack ...
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... In addition program memory may be mapped into data space, permitting code constants to be accessed as data memory. Figure 4 shows the DS2790’s memory map when executing from program memory space. See the MAXQ Family User's Guide: DS2790 Supplement for memory map information when executing from data or ROM space ...
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... Integrated Products. The 2-wire interface hardware can connection USB port using a USB to I Semiconductor. A commercial gang programmer can also be used for programming. 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector 2 C connection to another microcontroller converter such as the DS9123O, available from Dallas ...
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... Performing a program request over the 2-wire interface also invokes the bootstrap loader. The user must successfully complete a password match (If PWL = 1). The bootstrap loader functions are then fully supported over the 2-wire interface. When programming is complete, the exit loader function is used to reset the DS2790 and begin execution of the application software. ...
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... The watchdog timer in the DS2790 differs in two respects from the one described in the MAXQ Family User's Guide: 1) the clock used by the timer is the 70kHz OSCA clock that runs independently of the 1MHz OSCI (or system) clock, and 2) the watchdog interrupt is an asynchronous interrupt that can bring the processor out of stop mode ...
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... DS2790 enters the Brown-Out State. In Brown-Out State, the processor is halted without changing the instruction pointer voltage rises above V DD brown-out interrupt (if enabled). Otherwise state where it waits for a charger to be applied. When charge voltage is sensed on PLS, the DS2790 returns to the Brown-Out State where V DD Figure 3. DS2790 State Diagram Brown-Out VDD < ...
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... The peripheral registers define additional functionality that may be included by different products based on the MAXQ20 architecture. This functionality is broken up into discrete modules so that only the features required for a given product need to be included. Table 1 shows the DS2790 register set. Table 1. System Register Map ...
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... GRS.15 GRS.14 GRS.13 GRS.12 GRS.11 GRS.10 GRS.9 GRS.8 GRS.7 GRS.6 GRS.5 GRS.4 GRS.3 GRS.2 GRS.1 GRS.0 GRH GRXL GRXL.15 GRXL.14 GRXL.13 GRXL.12 GRXL.11 GRXL.10 GRXL.9 GRXL.8 GRXL.7 GRXL.6 GRXL.5 GRXL.4 GRXL.3 GRXL.2 GRXL.1 GRXL.0 FP DP[0] DP[1] 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector REGISTER BIT NUMBER CLR ...
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... GRL GRS 0 0 GRH GRXL DP0 0 0 DP1 0 0 Note: s indicates bit reflects pin state 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector REGISTER BIT ...
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... Note: Names that appear in italics indicate that all bits of a register are read-only. Names that appear in bold indicate that a register is 16 bits. All locations are bit addressable. 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector MODULE REGISTER INDEX M1 (1h) ...
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... TWSIM — — TWSCMD TWSCFG ADDR.6 ADDR.5 TWSTXD/RXD TWSFIF Note: Names that appear in italics indicate a read-only register bit. 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector REGISTER BIT NUMBER MSDI MSNDI MCCI MBEI MVI MCI ...
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... ICDA 0 0 ICDD 0 0 TWSINT 0 0 TWSIM 0 0 TWSCMD TWSCFG 0 0 TWSTXD/RXD TWSFIF Note: s indicates bit reflects pin state. 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector REGISTER BIT NUMBER ...
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... Their masks and their configuration bits, along with the RST pin status and control, are present in the EIC and PAF registers of module 0. 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector ...
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... A/D Converter CI TI Timer/ TCI Counter 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector MASK DESCRIPTION The interrupt from pin P0.0 is configurable PAF.0/PIE.0 via the PAF.0, PIT.0 and PIP.0 bits. The interrupt from pin P0.1 is configurable PAF.1/PIE.1 via the PAF.1, PIT.1 and PIP.1 bits. ...
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... I/O PORTS The DS2790 includes a simple input/output (I/O) data port. From a software perspective, the port appears as a group of Special Function Registers within module M0. The simple I/O port defined for this product is described below: · CMOS input buffers · Four open drain output drivers with selectable tri-state or weak pullups · ...
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... PMM.1 Ports P0.0 and P0.1 SDA/SCL PULL-UP SDA/SCL IN SDA/SCL OUT SCL and SDA 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector PIP.x X Interrupt Disabled 0 Interrupt Enabled, Triggered on Logic Low 1 Interrupt Enabled, Triggered on Logic High 0 Interrupt Enabled, Triggered on Falling Edge 1 Interrupt Enabled, Triggered on Rising Edge PPU ...
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... Configuration of the 2-wire interface is handled through the TWS Configuration register (TWSCFG) allowing system software to change the DS2790’s slave address, control handshaking on the clock line, and control bus timeout settings. The asynchronous interface between the TWS and MAXQ20 core is handled by TWS generated interrupts reported in the Interrupt register (TWSINT) and controlled in Interrupt Mask Register (TWSIM) ...
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... TWSCMD register is busy, the 2-wire hardware will not acknowledge (Nack) the command byte. The master can re-attempt to send the command byte until it is Ack’ed. 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector FORMAT 2-Wire Slave Address. R/W ...
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... FIFO) until read by the CPU. Data to be transmitted by the DS2790 is stored in a separate 8-byte transmit FIFO buffer (TXD FIFO) until the master reads it. If the RXD FIFO buffer becomes completely full or the TXD FIFO buffer becomes completely empty during communication, the interface will begin clock extending the bus to maintain data integrity ...
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... ACK symbol will be extended until a timeout occurs or the RXD FIFO has been read and is no longer full. Clock extending during a DS2790 transmit event (master read), is applied to delay the rising edge of SCL just after the ACK symbol following the address, and to any ACK symbols thereafter. If the TXD FIFO is empty, the clock low time just after the ACK symbol will be extended until a timeout occurs of the TXD FIFO has been written and is no longer empty ...
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... DS2790 2-Wire Programming Request Slave S Wr Ack FEh Address Command Enable Master to Slave Slave to Master 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector Data Data Byte ... Ack Ack Ack Byte 1 8 Potential Clock Extension when RXD is full . CMD_HM_DIS = 0, and CMD_HM = 0 ...
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... Programs should read a measurement value as a word to ensure that the value does not change between instructions. The DS2790 current measurement system is designed to provide timely data on charge and discharge current at a moderate resolution level while simultaneously accumulating high resolution average data to support accurate coulomb counting ...
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... Average Current register have a maximum offset of ±4 bits (±7.8125µV). Current Accumulation The DS2790 measures current for coulomb-counting purposes, with an accuracy of ±2% ±3.9µV over a range of ±64mV. Using a 15mΩ sense resistor, current accumulation is performed over a range of ±4.26A while measuring standby currents with an accuracy of ± ...
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... Temperature Measurement The DS2790 uses an integrated temperature sensor to continually measure battery temperature. Temperature measurements are updated in the Temperature register every 220ms in two’s-complement format with a resolution of 0.125°C over a ±127°C range. The Temperature register format is shown in Figure 16. ...
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... Figure 17. ADC Configuration Register Format ADDRESS 600AH Field Bit IBIAS 15:8 COCT 7:6 DOCT 5:4 SCDT 3 Reserved 2:1 OBEN 0 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector Word Address 6005h Format Accumulation Register Bias R/W 8-bit 2’s complement value that is added to the ACR on every update. Charge Overcurrent Threshold¾ ...
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... FETs, but is not able to override the protector and enable the FETs. During active operation (CPU or Analog mode), the DS2790 constantly monitors cell voltage and current to protect the battery from overcharge (overvoltage), overdischarge (undervoltage), excessive charge and discharge currents (overcurrent, short circuit), and extreme temperatures (overtemperature, undertemperature) ...
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... The DS2790 provides a test current of value the DS2790 shuts off the external discharge FET and sets the SCF bit in SCD from V to PLS to pull PLS up to detect the removal of the TST less than or equal to T ...
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... The DS2790 controls charging and discharging through external high-side N-FETs controlled through the CC and DC pins. An internal charge pump generates the voltage needed to drive the external FETs. An external capacitor connected between the CP and VSS pins stores the charge needed for the DS2790 to maintain the CC and DC outputs. To disable discharging, the DS2790 internally connects internally connects internally pulling CC and the CP voltage ...
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... Address Trim Key 7:0 ADDRESS 001Eh Field Bit IG 15:8 SRTC 7:0 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector to prevent damage. V OCP specification. Format R/W Undefined¾General purpose 2-Wire Slave Address R/W Valid only if Trim Key = 76h Default = 0001011b Trim Key Enables or disables all other user trim values. ...
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... UVT 12:8 TLIME 7 TLIM 6:5 OVT 4:0 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector Bit Definition Format Allowable Values R/W Undefined – General purpose R/W Undervoltage Threshold The Undervoltage threshold ranges from 2.30V to 2.90V and is calculated by the equation 2.90V – 0.0195V × UVT[4:0] ...
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... Debug mode can be invoked from background mode. · Debug mode allows the debug engine to take control of the CPU, providing read/write access to internal registers and memory, and single step trace operation. 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector UTILITY ROM DEBUG DEBUG ENGINE SERVICE ...
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... APPLICATIONS The low-power, high-performance RISC architecture of the DS2790 makes it an excellent fit for many portable or battery-powered applications that require cost-effective computing and analog measurement capability. The high- throughput core is programmable in-circuit over the 2-wire and JTAG interfaces, allowing for firmware upgrades, and ease of code development ...
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... Purchase components from Maxim Integrated Products, Inc., or one of its sublicensed Associate Companies, conveys a license under the 2 Philips I C Patent Rights to use these components defined by Philips. 4 DataSheet U .com DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector VIN 26 VDD 25 P0 ...