EZZE MASS2, Technical Manual, Page: 64 / 137

Model MASS 2 Version V_1.0
Prepared by H/W Date 22/01/2008
Subject Technical Manual Page 42/59
Figure 42. PMIC Charger Block Diagrams
Charger Detector
The charger detector senses the charging voltage from either a standard AC-DC adaptor or a USB connection.
When the charging input voltage is greater than the pre-determined threshold, the charging process is triggered.
The detector resists higher input voltages than other parts of the PMIC.
Charger Control
When the charger is on, this block controls the charging phase and turns on the appropriate LDOs according to the
battery status. The battery voltage is constantly monitored: if the voltage is greater than 4.3 V, charging is stopped
immediately to prevent permanent damage to the battery.
Control for Pre-Charge Indication
The PMIC provides 2 control signals SEL1 and SEL2 for the application that shows pre-charge status on the LCD.
In normal cases, VBAT is selected (SEL2 turned on) as the power input to the PMIC.