2003 Oct 31
19
Philips Semiconductors
Preliminary specification
Controller for power supply
and battery management
PCF50603
8.10
Real time clock (RTC)
The RTC module provides the time information to the
handset based on a 1 Hz clock frequency. Basically it is a
32-bit counter counting elapsed seconds.
The RTC module contains one alarm function that
generates an interrupt if the actual RTC time equals the
content of the alarm register. The alarm registers are
preset to all 1 s which effectively disables the alarm;
effectively no alarm interrupt will be generated as long
as the RTC counter does not overflow. It is
recommended to mask the ALARM interrupt before a
new value is written to the alarm registers, in order to
prevent interrupts during the write actions (a new setting
may require up to 4 register writes).
The RTC module is able to generate an interrupt each
second (SECOND interrupt) as well as each minute
(MINUTE interrupt). When the RTC starts up the first
time (after transition from NOPOWER state) the minute
interrupt is aligned with each 60 seconds crossing. If the
synchronization with the 60 second crossing is required
after reprogramming the RTC time registers it is up to
the software to program the RTC time registers with a
modulo 60 value.
8.11
Pulse-width modulator (PWM1 and PWM2)
The two PWMs (PWM1 and PWM2) offer the following
features:
Programmable frequency and duty cycle
Any of the GPOs can be connected to either the PWMs
or the inverse of the PWMs
The PWMs can be independently enabled in ACTIVE
state. In all other states the PWMs are disabled.
8.12
LED modulator (LED1 and LED2)
The PCF50603 contains two LED modulators (LED1 and
LED2), which can be selected as input for any of the GPO
outputs. The LED modulator of the PCF50603 is used for
the control of the indicator LEDs. They offer the following
features:
The LED driver can select eight different repetition
periods
Capable of generating eight different blinking patterns.
The selected pattern is generated once per repetition
period
The LED can be used as a status indicator during the
ACTIVE state or when a charger is connected.
8.13
General purpose outputs (GPO)
The PCF50603 contains three high current (100 mA)
open-drain GPOs. They offer the following features:
Each GPO can be configured as a constant LOW level,
a high impedance, a LED modulator output, a PWM
output or as the complementary PWM output PWM
The GPOs can sink 100 mA from any supply or battery
voltage.