Nokia 8550 서비스 매뉴얼
NSM–3/3D
System Module
System Module
PAMS Technical Documentation
Page 16
Issue 4 02/2002
Nokia Corporation
The voltage limit (VLIM1 or VLIM2) is selected by logic LOW or logic
HIGH on the CHAPS (N101) VLIM input pin. In NSM–3 phones VLIM is
fixed low in HW.
HIGH on the CHAPS (N101) VLIM input pin. In NSM–3 phones VLIM is
fixed low in HW.
When the switch in output overvoltage situation has once turned OFF, it
stays OFF until the the battery voltage falls below VLIM and PWM = LOW
is detected. The switch can be turned on again by setting PWM = HIGH.
stays OFF until the the battery voltage falls below VLIM and PWM = LOW
is detected. The switch can be turned on again by setting PWM = HIGH.
PWM (1 Hz)
VOUT
VLIM
t
SWITCH
ON
OFF
VCH
t
VCH<VOUT
ON