User Guide

NHM-8NX
System Module & UI PAMS Technical Documentation
Page 36 ãNokia Corporation Issue 1 05/02
NHM-8NX supports Li-Ion batteries.
Figure 11: Mechanical layout and interconnections of DCT-4 battery
Table 27: Pin numbering of battery pack
The BSI fixed resistor value indicates type and default capacity of a battery. NTC-resistor
BTEMP measures the battery temperature.
Temperature and capacity information are needed for charge control. These resistors are
connected to BSI and BTEMP pins of battery connector. Phone has 100 kΩ pull-up resis-
tors for these lines so that they can be read by A/D inputs in the phone.
External Audio
NHM-8NX is designed to support fully differential external audio accessory connection.
A headset and PPH-1 can be directly connected to system connector. Detection of the
different accessories is made in analog way by reading the DC voltage value of EAD con-
verter.
Signal name Pin number Function
VBAT 1 Positive battery terminal
BSI 2 Battery capacity measurement
(fixed resistor, connected to GND, inside the battery pack)
BTEMP 3 Battery temperature measurement
(measured by ntc resistor connected to GND inside pack)
GND 4 Negative/common battery terminal