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
μ
F 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.