TRF6900

SINGLE-CHIP RF TRANSCEIVER

SLAS213C – SEPTEMBER 1999 – REVISED MAY 2000

21

POST OFFICE BOX 655303

power amplifier

The power amplifier (PA) can be programmed via two bits (P0 and P1 in the D-word) to provide varying output

power levels. Several control loops are implemented internally to set the output power and to minimize the

sensitivity of the power amplifier to temperature, load impedance, and power supply variations. The output stage

of the PA usually operates in Class-C and enables easy impedance matching. PA_OUT, terminal 5, is an open

collector output terminal.

2

–2

2

–0.5

0.5

1

1

↑1 U

5

1

0.5

0.2

0

–1

–5

START 850 MHz

STOP 950 MHz

CH1 S22

CAL

OFS

CPL

FIL

1k

10

Figure 22. Power Amplifier Output Impedance (S22) at Device Terminal 5