ZHCSJM7 April 2019 BQ79606A-Q1
PRODUCTION DATA.
As the name suggests, ACTIVE mode enables the full functionality of the BQ79606A-Q1. All of the LDOs and references are enabled and the BQ79606A-Q1 is ready to do ADC conversions, cell balancing, and full communication to all of the devices in the daisy chain. Before enabling any of these functions, the host must wait for the BQ79606A-Q1 to fully start up. It takes approximately tSU(WAKE) for the BQ79606A-Q1 to transition to ACTIVE mode and have full functionality available. Following a SOFT_RESET, Digital Reset , or normal WAKEUP from SHUTDOWN, the host must clear the SYS_FAULT1[DRST] bit (using the SYS_FLT1_RST[DRST_RST] bit) to clear NFAULT and start the heartbeat (if enabled). ADVDD OSC fault may be also be triggered and must be cleared. Table 6 specifies all of the functionality that are enabled or available in ACTIVE mode.
The flow diagram (Figure 21) indicates several different ACTIVE states. These are not actual states, but correspond to the possible actions done while in ACTIVE. These correspond with the specifications in the Electrical Characteristics table that are split into these items:
During ACTIVE mode, if a WAKEUP command (either WAKEUP toggle on base device or WAKE tone on stack device) is received, the BQ79606A-Q1 resets to the system default values and forwards it to the next device and sets the SYS_FAULT1[DRST] bit to signal to the host that a reset has occurred. If a SLEEPtoACTIVE command is received, the BQ79606A-Q1 forwards it up the stack and continues operating with no changes.
The BQ79606A-Q1 exits ACTIVE mode and enters SLEEP mode if the SLEEP command is set (CONTROL1[GOTO_SLEEP]). The BQ79606A-Q1 exits ACTIVE mode and enters SHUTDOWN mode if no valid communication frames are received for the time set in the register (COMM_TO[LONG]) if enabled. Additionally, the IC enters SHUTDOWN mode if a thermal shutdown event occurs, or if the SHUTDOWN command is set (CONTROL1[GOTO_SHUTDOWN]). Table 24 specifies the mode transition for ACTIVE mode response to the different tones for stack devices. Table 23 specifies the mode transition for ACTIVE mode response to the different signals for base devices.
| SHUTDOWN | SLEEP | ACTIVE | |
|---|---|---|---|
| OV/UV Comparators | X | X | |
| OT/UT Comparators | X | X | |
| Communications | X | ||
| Cell Balancing | X | X | |
| WAKE Tone | X | X | X |
| WAKEUP Detection | X | X | X |
| SLEEPtoACTIVE Detection | X | X | |
| SHUTDOWN Detection | X | X | |
| ADC Reads | X | ||
| FAULTDET Tone | X | X | |
| GPIO FAULT | X | X | |
| SPI Master | X | ||
| Communication Timeout | X |