Philips BGA6489 - Manual (Page 7)

BGA6489_2 © NXP B.V. 2009. All rights reserved.
Product data sheet Rev. 02 — 15 June 2009 7 of 13
NXP Semiconductors
BGA6489
MMIC wideband medium power amplifier
8. Application information
Figure 10 shows a typical application circuit for the BGA6489 MMIC. The device is
internally matched to 50
Ω
and therefore does not require any external matching. The
value of the input and output DC blocking capacitors C1 and C2 depends on the operating
frequency; see
Table 9 . Capacitors C1 and C2 are used in conjunction with L1 and C3 to
fine tune the input and output impedance. Capacitor C4 is a supply decoupling capacitor.
A 1
µ
F capacitor (C5) can be added for optimum supply decoupling. The external
components should be placed as close as possible to the MMIC. When using via holes,
use multiple via holes per pin in order to limit ground path induction. Resistor R1 is a bias
resistor providing DC current stability with temperature.
V
S
= 8 V; R
bias
= 39 Ω .
Fig 9. Supply current as function of operating junction temperature; typical values
I
s
(mA)
− 40 40 − 20 0 60 80
T j ( ° C)
20
60
100
90
70
80
mgx408
(1) Optional capacitor for optimum supply decoupling.
(2) R1 values at operating supply voltage:
V
S
= 6 V; R1 = 27
Ω
.
V
S
= 8 V; R1 = 39
Ω
.
V
S
= 11 V; R1 = 82
Ω
.
Fig 10. Typical application circuit
50 Ω
microstrip C1 C2
C3
L1
V S
50 Ω
microstrip
C4 C5(1)
R1(2)
mgx419
1 V
D
2
3