L9634

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mode SPI bit definition.

OSD is able to differentiate short to battery, open circuit, and short to ground. A resistance measurement

provides the resistance value of a load connected between SQH and SQL. MOS diagnostic verifies the

functionality of the high and low side MOS. Refer to Figure 14 for the diagnostic diagram. A detailed op-

eration for each test is described in sections below.

Figure 14. Diagnostic Diagram

Figure 15. Diagnostic Flow Chart

Diagnostics

s1

A/D Converter

Data registers

8 to 1

Mux

s0

s2

SPI

SCLK

CS

MISO

MOSI

SQLx

SG

th

SQHx

I

SRC

VIGN

I

SINK

VRESx

I

BIAS

V

BIAS

SB

th

OC

th

I

PD

GNDx

gnd0

Monitor Mode

Run On-chip

Diagnostic

No

Short to

Ground

Yes

Resistance

Measurement

Indicate

Short to Ground

Yes

No

FET Test

enabled

No

Yes

Indicate

No Fault

LS FET

failed

Yes

No

Indicate

LS FET failed

HS FET

failed

Yes

No

Indicate

HS FET failed

Low Side Driver FET

Test

High Side Driver FET

Test

Indicate

Open Circuit

Open Circuit

Yes

No

Indicate

Short to Battery

Short to Battery

Yes

No

Obsolete

Product(s)

- Obsolete

Product(s)