BQ2060SS Datasheet, PDF (19/59 Pages) Texas Instruments – SBS V1.1-COMPLIANT GAS GAUGE IC

bq2060
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• Battery Address with R/W = 1: 0x17
• RemainingCapacity(): 0x03e9
For 0x160f17e903, the bq2060 transmits a PEC of 0xe8 to the host.
SLUS035E – JANUARY 2000 – REVISED OCTOBER 2005
PEC Enable in Master Mode
PEC for master mode broadcasts to the charger, host, or both can be enabled/disabled with the combination the
bits HPE and CPE in Control Mode.
SMBus On and Off State
The bq2060 detects whether the SMBus enters the Off state by monitoring the SMBC and SMBD lines. When
both signals are continually low for at least 2.5 s, the bq2060 detects the Off state. When the SMBC and SMBD
lines go high, the bq2060 detects the On state and can begin communication within 1 ms. One-MΩ pulldown
resistors on SMBC and SMBD are recommended for reliable Off tate detection.
HDQ16
The HDQ16 interface is a command-based protocol. (See Figure 10.) A processor sends the command code to
the bq2060. The 8-bit command code consists of two fields, the 7-bit HDQ16 command code (bits 0–6) and the
1-bit R/W field. The R/W field directs the bq2060 either to
• Store the next 16 bits of data to a specified register or
• Output 16 bits of data from the specified register
With HDQ16, the least significant bit of a data byte (command) or word (data) is transmitted first.
A bit transmission consists of three distinct sections. The first section starts the transmission by either the host or
the bq2060 taking the HDQ16 pin to a logic-low state for a period t_STRH;B. The next section is the actual data
transmission, where the data bit is valid by the time, t_DSU;B after the negative edge used to start communication.
The data bit is held for a period t_DH;DV to allow the host processor or bq2060 to sample the data bit.
The final section is used to stop the transmission by returning the HDQ16 pin to a logic-high state by at least the
time t_SSU;B after the negative edge used to start communication. The final logic-high state should be until a period
t_CYCH;B to allow time to ensure that the bit transmission was stopped properly.
If a communication error occurs (e.g., t_CYCB > 250µs), the host sends the bq2060 a BREAK to reinitiate the serial
interface. The bq2060 detects a BREAK when the HDQ16 pin is in a logic-low state for a time t_B or greater. The
HDQ16 pin is then returned to its normal ready-high logic state for a time t_BR. The bq2060 is then ready to
receive a command from the host processor.
The HDQ16 pin is open drain and requires an external pullup resistor.
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Figure 10. HDQ16 Communication Example
Command Codes
The SMBus Command Codes are in (), the HDQ16 in [ ]. Temperature(), Voltage(), Current(), and
AverageCurrent(), performance specifications are at regulated V_CC (V_RO) and a temperature of 0°C–70°C.
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