Nokia 9210i Servicehandbuch

PAMS

Technical Documentation

RAE-5 

3. RF+System Module KL8 

Page 3 – 28

Issue 1 04/02

The PWM pulse width is controlled by the MPU in MADLinda which sends a
control value to CCONT through a serial control data bus. The main battery
voltage rise is limited to a specified level by turning the switch off. Lower limit
(4.8V) in CHAPS is permanently selected because only lithium batteries are
supported. Charging current is monitored by measuring the voltage drop across
a sensor resistor.

* Wake–Up Charge
* Voltage protect

* 4.2V Li–Ion

* A/D conversion

* PWM output
* Serial data in/out

CHARGE 
CONTROL
(PWM in 2–wire
concept)

CHARGER
SENSING

SERIAL DATA

CHARGER

AND BATTERY

INTERRUPT

DSP

MPU

ASIC

CHARGE 
CONTROL
(PWM in 3–wire
concept)

Connect/disconnect

detection

*

BATTERY SENSING:
*  Voltage
*  Size/type
*  Temperature

Figure 5.

Block diagram of charge control in RAE-5

Power–up reset signal, PURX, is the main reset in RAE-5. PURX is generated
by CCONT during power–on. The watchdog within CCONT is enabled and
must be fed periodically to keep CCONT (and whole device) powered on.
PURX –signal is connected to MADLinda’s reset input (PURX). Figure 6 shows
the board/module level reset scheme in RAE-5.