L9958 datasheet(17/38 Pages) STMICROELECTRONICS

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L9958

Current regulation

Doc ID 17269 Rev 5

17/38

Figure 12.

Temperature dependent current regulation

4.2

Current regulation with low-inductive loads

Each time output stages are turned off, an internal timing starts for duration Toff-min.

Whenever turn-on is reached in a time Toff that is shorter than Toff-min, output stages are

kept OFF, until Toff-min is reached.

In such case the ripple control could be not so precise as specified.

Figure 13.

Current regulation with different loads

4.3

Slew rate control in case of current limitation on low-side

The slew rate control can be done on voltage and current or only on voltage. This can be

selected by SPI through the bit ISR_DIS.

The slew rate of each high-side power transistor of the bridge is controlled either during

turn-on and turn-off (current AND voltage slew rate). The same setting is applied for both

switching. Moreover, this slew rate is configurable by SPI in order to get the best trade-off

between conducted/radiated EMI and power dissipation during switching. The slew rate

L9958 Datasheet(PDF) 17 Page - STMicroelectronics