JAJSGV8B September 2019 – December 2019 DRV8904-Q1 , DRV8906-Q1 , DRV8908-Q1 , DRV8910-Q1 , DRV8912-Q1
UNLESS OTHERWISE NOTED, this document contains PRODUCTION DATA.
A current-limit circuit on each MOSFET limits the current through the MOSFET by removing the gate drive signal. If this current limit stay active for longer than the tOCP deglitch time, the high-side and the low-side FETs in the corresponding half bridge are disabled and the nFAULT pin is driven low. The OCP bit in the IC status (IC_STAT) register and corresponding bit in overcurrent protection status register (OCP_STAT_X) register is latched high. The charge pump remains active during this condition. The OCP bit in the IC status (IC_STAT) register and corresponding bits (HBX_HS_OCP / HBX_LS_OCP) in overcurrent protection status register (OCP_STAT_X) register remains set until cleared through the CLR_FLT bit.
User also has the programmability of disabling the OCP fault on the nFAULT pin by setting the OCP_REP bit in the CONFIG_CTRL register.
The device also provides two slew-rate options for the device turn-off during an OCP event which can be programmed via the PL_MODE_EN bits in OLD_CTRL_2 register. The default option (PL_MODE_EN = 00b) is the faster slew rate option (typical around 1µs) which can be used for the single bridge operation. The slower option (PL_MODE_EN = 01b) provides a slower slew rate (half-bridge slew rate, HBX_SR) which can be used for the higher current applications in device parallel mode operation.
Drive
Current |
BRIDGE
CONFIGURATION |
REGISTER
SETTINGS |
BRIDGE
STATE |
nFAULT PIN | BITS
AFFECTED |
RECOVERY | |
---|---|---|---|---|---|---|---|
OCP_REP
= 0 |
OCP_REP
= 1 |
||||||
ILOAD < IOCP | OUT1 High-Side ON | HB1_HS_EN = 1 | ENABLED | HIGH | HIGH | N/A | N/A |
OUT2 Low-Side ON | HB1_LS_EN = 1 | ENABLED | HIGH | HIGH | |||
ILOAD < IOCP | Full Bridge (OUT1/2)
Forward Direction |
HB1_HS_EN = 1
HB2_LS_EN = 1 |
ENABLED | HIGH | HIGH | ||
Full Bridge (OUT1/2)
Reverse Direction |
HB1_LS_EN = 1
HB2_HS_EN = 1 |
ENABLED | HIGH | HIGH | |||
ISHORT or ILOAD >
IOCP |
OUT1 High-Side ON
OUT1 Short to GND |
HB1_HS_EN = 1 | Hi-Z | LOW | HIGH | OCP = 1 (IC_STAT)
HB1_HS_OCP = 1 |
OCP Condition Removed
CLR_FLT = 1 |
OUT1 Low-Side ON
OUT1 Short to VM |
HB1_LS_EN = 1 | Hi-Z | LOW | HIGH | OCP = 1 (IC_STAT)
HB1_LS_OCP = 1 |
||
ISHORT or ILOAD >
IOCP |
Full Bridge (OUT1/2)
Forward Direction OUT1 / OUT2 Short |
HB1_HS_EN = 1
HB2_LS_EN = 1 |
Hi-Z | LOW | HIGH | OCP = 1 (IC_STAT)
HB1_HS_OCP = 1 or HB2_LS_OCP = 1 (1) |
|
Full Bridge (OUT1/2)
Reverse Direction OUT1 / OUT2 Short |
HB1_LS_EN = 1
HB2_HS_EN = 1 |
Hi-Z | LOW | HIGH | OCP = 1 (IC_STAT)
HB1_LS_OCP = 1 or HB2_HS_OCP = 1 (2) |