Siemens A55 - Call Records

V1.20 Page 31 of 48 ICM MP CCQ GRM
A55/C55_Hitachi Company Confidential © Copyright Siemens AG 04/03
Functions
Pin
Requirements
Sequence
Voltage Supply
Logics
REG3
(2.65V)
The linear controller is designed for
2.65V(±3%) and a maximum load current of
220 mA.
It will consist basically of an internal operation
amplifier, an integrated p-channel output
transistor as well as a capacitor (C = 2.2µF) for
stabilizing the voltage. The required reference
voltage for the regulating circuit will be
generated internally via a bandgap. The
negative feedback of the regulating circuit shall
be done via chip-internal resistances.
Voltage Supply
RF
VREGRF1,
RF_EN,
RESET_N
The linear controller is designed for 2.85V(min.
2.79V, max. 2.91V) and a maximum load
current of 120 mA.
Voltage and current for RF-VCO and
Transceiver is supplied from the internal 2.85V
LDO. The operating voltage RF12LDO is kept
constant up to the maximum rated load current.
A reference voltage for the regulator circuit is
generated from a bandgap reference. A low
noise must be guaranteed.
RF1LDO is controlled by RF_EN. If it is set to
high, the regulator is enabled. The control
method can be modified by TWI interface
between external and internal control mode. If
internal control mode is set, RF1LDO can only
be enabled by TWI bit. In external mode,
RF1LDO can only be enabled by RF_EN.
RF1LDO is released with rising edge of
RESET_N signal.
Voltage Supply
RF
VREGRF2,
SLEEP1_N,
SLEEP2_N,
POWER_ON
The linear controller is designed for 2.85V(min.
2.79V, max. 2.91V) and a maximum load
current of 180 mA.
Voltage and current for RF-VCO and
Transceiver is supplied from the internal 2.85V
LDO. The operating voltage RF2LDO is kept
constant up to the maximum rated load current.
A reference voltage for the regulator circuit is
generated from a bandgap reference. A low
noise must be guaranteed.
RF2LDO is controlled by VCXO_EN (PinH1). If
it is set to high, the regulator is enabled. The
control method can be modified by TWI
interface between external and internal control
mode. If internal control mode is set, RF2LDO
can only be enabled by TWI bit. In external
mode, RF2LDO can only be enabled by
VCXO_EN (PinH1).
RF2LDO is released with rising edge of
POWER_ON signal.