PA2423U
RangeChargerTM 2.4 GHz Bluetoothtm Power Amplifier IC
Preliminary
Applications Information
For test and design purposes, SiGe Semiconductor offers an evaluation board for the PA2423U. The order part
number for the evaluation board is PA2423U-EV1. The evaluation board is intended to simplify the testing with
respect to RF performance of this power amplifier.
The application note, 131-DST-02 provides the supporting information for using the evaluation board. It contains
information on the schematic, bill of materials and recommended layout for the power amplifier and the input and
output matching networks. To assist in the design process, this layout is available, upon request, in gerber file format.
Using VRAMP
V
RAMP is a digital pin used to power-up and power-down the PA2423U in time division duplex systems such as
BluetoothTM 1.1. During receive mode, VRAMP voltage is pulled down, PA2423U acts as a 35 dB isolation block
between the radio and the antenna while consuming a modest 1 µA. In transmit mode, VRAMP voltage is pulled to VCC
and PA2423U offers 19 dB to 21 dB of large signal gain.
Using VCTL
V
CTL is an analog pin that is designed to control the gain of PA2423U. Applying a voltage between 0 V and VCC will
adjust the gain between -15 dB and 21 dB. Used in combination with a variable drive level to PA2423U, the VCTL
function can greatly optimize the PAE of the system at all four BluetoothTM transmitted power levels.
131-DST-01 Rev 1.1 Apr-18-2006
Confidential
9 of 10
QA041806
SIGE [ SIGE SEMICONDUCTOR, INC. ]
