L9969S datasheet(15/70 Pages) STMICROELECTRONICS

15 / 70 page

Figure 8. Overview of VDD voltage ranges

Device overall

Reset logic

VDD monitoring

Output stages

SPI function

VDD

18 V

5.6 V

VDD_THH

4.4 V

1.3 V

VDD_POR

VDD_MR_min

VDD_THL

2.6.2.4

Behavior on pin NABE in case of external short circuit

In case a short circuit on the PCB pulls both pins NABE and VDD for example, to the battery voltage (max. 18 V),

the internal power-stage at pin NABE is designed in such a way that the H-bridge is not damaged, in case NABE

is pulled-down internally to GND, even though an external battery voltage is applied low-ohmic to pin NABE. The

internal power-stage sustains such short-circuit for a few hours.

2.6.2.5

NABE Pin

NABE is a bidirectional pin (input and output). As an input function, all output power-stages are permanently

switched off if an external low signal is applied to pin NABE. NABE output is realized as an open drain low side

switch. During a VDD over-voltage (above VDD_THH) or undervoltage (below VDD_THL), the pin is pulled to GND

(logic low). Refer also to Section 2.6.2.4 Behavior on pin NABE in case of external short circuit in case of an

external short circuit at pin NABE.

The NABE-Pin is made redundant to the DIS-Pin to reach the ISO26262 Safety Goals. The NABE goes directly to

the Gate-Driver of the Bridge.

The default signal level of “NABE” (for example in case of ECU initialization) is low-level with integrated pull

down-current source.

L9969x

Power Supply

DS14029 - Rev 3

page 15/70

L9969S Datasheet(PDF) 15 Page - STMicroelectronics