L99DZ80EP datasheet(39/68 Pages) STMICROELECTRONICS

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L99DZ80EP

Application information

to be cleared through the SPI to reactivate the gate drivers. The drain source monitoring has

a filter time of typ. 6 µs. This monitoring is only active while the corresponding gate driver is

activated. If a drain-source monitor event is detected, the corresponding gate-driver remains

activated for at maximum the filter time. When the gate driver switches on, the drain-source

comparator requires the specified settling time until the drain-source monitoring is valid.

During this time, this drain-source monitor event may start the filter time. The threshold

voltage VSCd can be programmed using the SPI.

Figure 15. H-bridge diagnosis

3.19

H-bridge monitoring in off-mode

The drain source voltages of the H-Bridge driver external transistors can be monitored,

while the transistors are switched off. If either bit OL_H1L2 or OL_H2L1 is set to ‘1’, while bit

HEN = ‘1’, the H-drivers enter resistive low mode and the drain-source voltages can be

monitored. Since the pull-up resistance is equal to the pull-down resistance on both sides of

Table 26. H-bridge DS-monitor threshold

DIAG<1>

DIAG<0>

Monitoring threshold voltage (typical)

VSCD1 =0.5 V

VSCD2 =1.0 V

VSCD3 =1.5 V

VSCD4 =2.0 V

L99DZ80EP データシート(PDF) 39 Page - STMicroelectronics