HA16178P/FP

REJ03D0903-0100 Rev.1.00 Jun 12, 2007

Page 13 of 24

Description of Functions

1. UVL Circuit

The UVL circuit monitors the Vcc voltage. When the voltage is lower than 9.0 V, the IC is stopped. When the voltage

is higher than 10.5 V, IC is started.

When operation of the IC is stopped by the UVL circuit, the driver circuit output is fixed low, output of VREF is

stopped, and the oscillator is stopped.

VREF

VCC

10.5 V (VH)

5 V

4.0 V

CT

CAO

9 V (VL)

OUT

Figure 1 UVL Operation