BCR400W Datasheet, PDF (6/7 Pages) Siemens Semiconductor Group – Active Bias Controller (Supplies stable bias current even at low battery voltage and extreme ambient temperature variation)

BCR400W
RF transistor controlled by BCR400
BCR 400
+V _S
3
R _ext. V_drop
4
1
RF IN
Ι_C
2
C₁
C₂
Be aware that BCR400 stabilized
bias current of transistors in an active
control loop
In order to avoid loop ascillation
(hunting),
time constants must be chosen
adequately, i.e. C1 >= 10 x C2
Ι _contr.
RF OUT
RF-Transistor
EHA07217
RX/TX antenna switch, compatible to control logic
and working at wide battery voltage range
Antenna
λ/4
TX
RX
BCR 400
RX
TX
R_ext = 100 Ω - 220 Ω
1
4
2
3
6
+V_S > 2.7 V
EHA07218
Aug-07-2001