Analog Integrated Circuit Device Data

Freescale Semiconductor

19

33880

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

LOGIC COMMANDS AND REGISTERS

On each SPI communication, an 8-bit command word is sent to the 33880 and an 8-bit fault word is received from the 33880.

The Most Significant Bit (MSB) is sent and received first (see below).

Command Register Definition:

0 = Output Command Off

1 = Output Command On

Fault Register Definition:

0 = No fault

1 = Fault.

MSB

LSB

OUT8

OUT7

OUT6

OUT5

OUT4

OUT3

OUT2

OUT1

Table 6. Fault Operation

SERIAL OUTPUT (SO) PINS REPORTS

Overtemperature

Fault reported by Serial Output (DO) pin.

Overcurrent

DO pin reports short to battery/supply or overcurrent condition.

Output ON Open Load Fault

Not reported.

Output OFF Open Load Fault

DO pin reports output OFF open load condition.

DEVICE SHUTDOWNS

Overvoltage

All outputs assuming the previous state upon recovery from overvoltage.

Overtemperature

Only the output experiencing an overtemperature fault shuts down. Output assumes previous state

upon recovery from overtemperature.