Vibrator - LG KS20 Operating Instructions Manual

4. TROUBLE SHOOTING

4.22 Vibrator

The PM7540 IC supports silent incoming-call alarms with its vibration motor driver. The vibration
driver is a programmable voltage output that is referenced to VDD; when off, its output voltage is
VDD. The motor is connected between VDD and pin N2 (VIB_DRV_N); the voltage across the motor
is Vm = VDD - Vout where Vout is the PM7540 IC voltage at pin N2.
A flyback diode is connected across the motor terminals to prevent inductive kickback during turn-off
and suppress voltage transients that could damage the IC. Short circuit current limiting is also
provided to limit the current when the motor is stalled or shorted. The driver is programmable from
1.2 to 3.1 V in 100-mV increments.
VIB_DRV_ON
LGE Internal Use Only
VPWR
KDS160E D700
C700
1u
- 134 -
L700
CN700
68nH
1
2
L701
68nH
ENEY0003801
24-8000-002-000-829
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes