V1.0 Page 33 of 46 ICM MP CCQ ST
C45, M50 AND MT50 Company Confidential © Copyright Siemens AG 05/02
Measurement of Battery and Ambient Temperature
The temperature is measured as a voltage equivalent of the temperature on the
voltage dividers R131,R136,R135 for the ambient temperature by the EGAIM.
The battery temperature is measured directly at (l3) of the EGOLD+. For this,
the integrated Σ∆ converter of the EGAIM of the RX-I base band branch is used.
This Σ∆ converter compares the voltage of TBAT and TENV internally with a
reference voltage BREF.
Via an analog multiplexer, either the RX-I base band signal, or the TBAT signal
and the TENV signal can be switched to the input of the converter.
The signal MEAS_ON from the EGOLD+(GSM TDMA-TIMER G11) activates the
measurement and is used to generate to BREF by the help of R137,R132
Measurement of the Battery Voltage
The measurement of the battery voltage is done in the Q-branch of the EGAIM.
for this BATT+ is connected via a voltage divider R118, R120 to the EGOLD+
(GAIM N2) (Input limitation 1.33V to 5.91V) .An analog multiplexer does the
switching between the baseband signal processing and the voltage
measurement.
To Next Page
Loading...
Need help?
General
