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4964B–AUTO–07/07

ATA6842

7.16

12V Switch

Via an SPI command, the voltage at pin V12 can be switched to pin V12S (see Table 7-9 on

page 25). The 12V switch has a current limitation.

7.17

Comparator

The ATA6842 has two comparators. They compare inputs CxI in reference to the bandgap volt-

age. There are no internal pull-ups or pull-downs. The output is a V5-based push-pull stage. A

hysteresis can be implemented by external resistors. Additionally, the output of comparator

number 1 can be read out via SPI.

7.18

TCFET Driver

The ATA6842 features a circuit to drive an external N-channel FET. The control voltage is gen-

erated by a charge pump with bootstrap circuit for faster power-up behavior. Activation is done

by an SPI command (see Table 7-9 on page 25).

7.19

UVM Voltage Monitoring

An undervoltage warning is indicated at output UVW if V12 falls below 3

× UVR. This reference-

voltage level can be adjusted by an external resistor divider. The undervoltage warning can be

tested with an SPI command.