DS2777 MAXIM [Maxim Integrated Products], DS2777 Datasheet
DS2777
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DS2777 Summary of contents
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... A Maxim 1-Wire (DS2775/DS2776) or 2-wire (DS2777/DS2778) interface provides serial communica- tion to access measurement and capacity data regis- ters, control registers, and user memory. The DS2776/DS2778 use the SHA-1 hash algorithm in a challenge-response pack authentication protocol for battery-pack verification ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication ABSOLUTE MAXIMUM RATINGS Voltage Range on PLS, CP, CC, DC Pins Relative to V .....................................................-0.3V to +18V SS Voltage Range SRC Pins ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication ELECTRICAL CHARACTERISTICS (continued +4.0V to +9.2V -20°C to +70°C, unless otherwise noted. Typical values are PARAMETER SYMBOL DQ, PIO, SDA Output ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication EEPROM RELIABILITY SPECIFICATION (V = +4.0V to +9.2V -20°C to +70°C, unless otherwise noted PARAMETER SYMBOL EEPROM Copy Time EEPROM Copy Endurance ELECTRICAL CHARACTERISTICS: 1-Wire ...
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... Note 3: Overvoltage (OV) and undervoltage (UV) delays (t detected within 100ms of entering active mode. Note 4: Timing must be fast enough to prevent the DS2777/DS2778 from entering sleep mode due to bus low for period > t Note 5: f must meet the minimum clock low time plus the rise/fall times. ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication (T = +25°C, unless otherwise noted.) A DISCHARGE-OVERCURRENT PROTECTION DELAY 2V/div 0V 2V/div 0V 1V/div 0V 20mV/div TIME (ms) DC ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication (T = +25°C, unless otherwise noted.) A CURRENT MEASUREMENT ACCURACY 125 75 -20°C +25°C 25 -25 +70°C -75 125 -0.052 -0.032 -0.012 0.008 0.028 0.048 V (mV) SNS PIN ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Li+ PLS PROTECTOR CC FET DRIVERS DC CP CHARGE V DD PUMP VOLTAGE REGULATOR VB VB INTERNAL FuelPack is a trademark of Maxim Integrated Products, Inc. 8 _______________________________________________________________________________________ VOLTAGE ...
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... DS2775/DS2776 Typical Application Circuit 1kΩ 1kΩ CC SRC DC PLS IN2 V DS2775 IN1 DS2776 PIO CP VB 0.47μF SNS V OVD SS SRC RSNS DS2777/DS2778 Typical Application Circuit 1kΩ 1kΩ CC SRC DC PLS V DD SDA V IN2 SCL V DS2777 IN1 DS2778 PIO CP VB 0.47μF SNS V SS SRC RSNS 150Ω ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Detailed Description The DS2775–DS2778 function as an accurate fuel gauge, Li+ protector, and SHA-1-based authentication token (SHA-1-based authentication available only on the DS2776/DS2778). The fuel gauge provides accu- rate ...
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... SLEEP ACTIVE PSPIO = 1 PMOD = 1 PSDQ = 1 UVEN = 1 Figure 2. Sleep-Mode State Diagram for DS2777/DS2778 If either of the voltages on (V exceeds the overvoltage threshold, V longer than overvoltage delay, t ven low to shut off the external charge FET and the OV flag in the Protection register is set. The DC output remains high during overvoltage to allow discharging ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Table 1. Li+ Protection Conditions and DS2775/DS2776 Responses CONDITION THRESHOLD Overvoltage (OV) (Note 1) V CELL Undervoltage (UV) (Note 1) V CELL Overcurrent, Charge (COC) V SNS Overcurrent, Discharge ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Undervoltage (UV) If the average of the voltages drops below the undervoltage threshold, IN1 for a period longer than undervoltage ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Temperature Measurement The DS2775–DS2778 use an integrated temperature sensor to measure battery temperature with a resolution of 0.125°C. Temperature measurements are updated every 440ms and placed in the Temperature ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Current Offset Correction Every 1024th conversion, the ADC measures its input offset to facilitate offset correction. Offset correction occurs approximately once per hour. The resulting cor- rection factor is ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication FRSGAIN value is provided to preserve the factory cali- bration value only and is not used to calibrate the current measurement. The 16-bit FRSGAIN value is readable from addresses ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Accumulation Bias In some designs a systematic error or an application preference requires the application of an arbitrary bias to the current accumulation process. The Current Accumulation Bias register ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication VOLTAGE (R) TEMPERATURE (R) CURRENT (R) ACCUMULATED CURRENT (ACR) (RW) AVERAGE CURRENT (R) CELL MODEL PARAMETERS (EEPROM) AGING CAPACITY (AC) (2 BYTES EE) AGE SCALAR (AS) (1-BYTE EE) SENSE-RESISTOR ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication SEGMENT 1 100% DERIVATIVE (ppm/°C) Figure 14. Cell Model Example Diagram read from the Current register. The specified minimum voltage, or active-empty voltage (VAE), should be a 110ms average ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication -10 full with a resolution Standby empty at +40°C is, by definition, zero and therefore no storage is required. The slopes (derivatives) of the four segments ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Minimum Charge Current (IMIN) IMIN stores the charge-current threshold used to detect a fully charged state stored as a 1-byte value with units of 50µV (IMIN x ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication count-based estimation is reset after a learn cycle. The cycle-count-based estimation is used only in the absence of a learn cycle. ACR Housekeeping The ACR value is adjusted occasionally ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication MSB—ADDRESS 02h MSb Figure 16. Remaining Active Absolute Capacity (RAAC) [mAh] The RAAC register reports the capacity available under ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication The Protection register reports events detected by the Li+ safety circuit on bits [7:2]. Bits 0 and 1 are used to disable the charge and discharge FET gate drivers. ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication The Status register contains bits that report the device status. All bits are set internally. The CHGTF, AEF, SEF, LEARNF, and VER bits are read-only. The UVF and PORF ...
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... PIO pin. This control is independent of the PSDQ state. Bit 0: Power-Switch DQ Enable (PSDQ). A value of 1 enables the DQ pin as a power-switch input. A value of 0 dis- ables the power-switch input function on DQ pin. This control is independent of the PSPIO state. This bit has no effect in the DS2777/DS2778. Table 4. Undervoltage Threshold VUV[1:0] BIT FIELD ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication The 8-bit Overvoltage Threshold register (VOV) sets the overvoltage threshold for the protection circuitry. An over- voltage condition is detected if either of the voltages on V the VOV ...
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... X Bits Reserved. Bit 1: SHA Idle Bit (SHA_IDLE). For the DS2777/DS2778, this bit reads logic 1 while an SHA calculation is in progress and reads logic 0 when the calculation is complete. Bit 0: PIO Pin Sense and Control Bit (PIOB). Writing the PIOB bit activates the PIO pin open-drain output driver, forcing the PIO pin low ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication The EEPROM register provides access control of the EEPROM blocks. EEPROM blocks can be locked to prevent alteration of data within the block. Locking a block disables write access ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication The DS2775–DS2778 have a 256-byte linear memory space with registers for instrumentation, status, and control, as well as EEPROM memory blocks to store parameters and user information. Byte addresses ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Table 8. Parameter EEPROM Memory Block ADDRESS DESCRIPTION (HEX) 60h Control Register 61h Accumulation Bias Register (AB) 62h Aging Capacity Register MSB (AC) 63h Aging Capacity Register LSB (AC) ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Table 9. Memory Map (continued) ADDRESS (HEX) 13h Accumulated Current Register LSB - 2 14h Age Scalar Register 15h Special Feature Register 16h Full Register MSB 17h Full Register ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Challenge command. The host then issues the Compute MAC or Compute MAC with ROM ID command. The MAC is computed per FIPS 180, and then returned as a 160-bit ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Table 11. Secret Loading Function Commands COMMAND Clear Secret Compute Next Secret without ROM ID Compute Next Secret with ROM ID Lock Secret the new secret value to EEPROM. ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication also used to provide verification of error-free data trans- fer as each EEPROM page is sent to the master during a Read Data/Generate CRC command and for the 8 ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication Match Net Address [55h] This command allows the bus master to specifically address one DS2775/DS2776 on the 1-Wire bus. Only the addressed DS2775/DS2776 responds to any sub- sequent function ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication or if setting the LOCK bit to 1 does not immediately precede the Lock command, the Lock command has Table 12. All Function Commands COMMAND Write Challenge Compute MAC ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication 1-Wire SKIP-ROM RESET COMMAND PRESENCE COMPUTE PULSE MAC COMMAND Figure 25. Compute MAC Function Command 1-Wire SKIP-ROM RESET COMMAND PRESENCE COMPUTE PULSE NEXT SECRET COMMAND Figure 26. Compute Next ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication 1-Wire SKIP-ROM RESET COMMAND PRESENCE PULSE Figure 28. Clear/Lock Secret, Set/Clear Overdrive Function Commands DQ LINE TYPE LEGEND: Figure 29. 1-Wire Initialization Sequence 1-Wire Signaling The 1-Wire bus requires ...
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... The DS2777/DS2778’s SDA pin operates bidi- rectionally, that is, when the DS2777/DS2778 receive data, SDA operates as an input, and when the DS2777/DS2778 return data, SDA operates as an open- drain output with the host system providing a resistive pullup. The DS2777/DS2778 always operate as a slave ...
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Stand-Alone, Li+ Fuel-Gauge IC with Protector and Optional SHA-1 Authentication V PULLUP GND MIN MODE: 15μs 15μs STANDARD 2μs OVERDRIVE t RDV V PULLUP GND MODE: 15μs STANDARD 2μs OVERDRIVE LINE TYPE LEGEND: Figure 30. 1-Wire Write and Read ...
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... R BIT 7 BIT 6 BIT Bits Slave Address (A[6:0]). A[6:0] contains the 7-bit slave address of the DS2777/DS2778. The factory default is 0110100b. Bit 0: Reserved. 42 ______________________________________________________________________________________ Data Order selects a read transaction, with the subsequent bytes being read from the slave by the master ...
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... EEPROM blocks, as well as a write that auto-increments to the Function Command register (address FEh). Incomplete bytes and bytes that are not acknowledged by the DS2777/DS2778 are not written to memory. As noted in the Memory section, writes to unlocked EEPROM blocks modify the shadow RAM only. ______________________________________________________________________________________ ...
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... No V IN1 No VB Yes V SS Yes *EXPOSED PAD DOCUMENT NO. 56-G0010-001 is a registered trademark of Maxim Integrated Products, Inc 2ms EEC Pin Configuration SRC 3 12 SCL/OVD DS2775 4 DS2776 11 SDA/DQ DS2777 5 10 PLS DS2778 6 9 PIO * SNS TDFN-EP × (3mm 5mm) ...