MHW804–1 MHW804–2

4

MOTOROLA RF DEVICE DATA

APPLICATIONS INFORMATION

NOMINAL OPERATION

All electrical specifications are based on the nominal con-

ditions of Vs1 = Vs2 = Vs3 = Vs4 = Vs5 = 7.5 Vdc (Pins 2, 3, 4,

5, 6) and Pout equal to 4.0 watts. With these conditions, maxi-

mum current density on any device is 1.5 x 105 A/cm2 and

maximum die temperature with 100

°C case operating tem-

perature is 165

°C. While the modules are designed to have

excess gain margin with ruggedness, operation of these

units outside the limits of published specifications is not rec-

ommended unless prior communications regarding intended

use have been made with the factory representative.

GAIN CONTROL

The module output should be limited to 4.0 watts. The pre-

ferred method of power output control is to fix Vs1 = Vs2 = Vs3

= Vs4 = Vs5 = 7.5 Vdc (Pins 2, 3, 4, 5, 6), Pin (Pin 1) at 1.0

mW, and vary Vcont (Pin 1) voltage.

DECOUPLING

Due to the high gain of the three stages and the module

size limitation, external decoupling networks require careful

consideration. Pins 2, 3, 4, and 6 are internally bypassed

with a 0.018

µF chip capacitor which is effective for frequen-

cies from 5.0 MHz through 925 MHz. For bypassing frequen-

cies below 5.0 MHz, networks equivalent to that shown in

Figure 1 are recommended. Inadequate decoupling will re-

sult in spurious outputs at certain operating frequencies and

certain phase angles of input and output VSWR.

LOAD MISMATCH

During final test, each module is load mismatch tested in a

fixture having the identical decoupling networks described in

Figure 1. Electrical conditions are Vs1 = Vs2 = Vs3 = Vs4

= Vs5 equal to 9.0 V, VSWR equal to 20:1, and output

power equal to 6.0 watts.