MRF842

2

MOTOROLA RF DEVICE DATA

Characteristic

Symbol

Min

Typ

Max

Unit

ON CHARACTERISTICS

DC Current Gain

(IC = 2.0 Adc, VCE = 5.0 Vdc)

hFE

10

—

—

—

DYNAMIC CHARACTERISTICS

Output Capacitance

(VCB = 12.5 Vdc, IE = 0, f = 1.0 MHz)

Cob

—

45

65

pF

FUNCTIONAL TESTS

Common–Base Amplifier Power Gain

(Pout = 20 W, VCC = 12.5 Vdc, f = 870 MHz)

GPB

6.0

7.0

—

dB

Collector Efficiency

(Pout = 20 W, VCC = 12.5 Vdc, f = 870 MHz)

η

50

55

—

%

Load Mismatch Stress

(VCC = 15.5 Vdc, Pin (3) = 6.0 W, f = 870 MHz,

VSWR = 20:1, all phase angles)

—

No Degradation in Output Power

NOTE:

3. Pin = 150% of the typical input power requirement for 20 W output power @ 12.5 Vdc.

Figure 1. 870 MHz Test Circuit Schematic

B — Ferrite Bead, Ferroxcube 56–590–65–3B

C1, C11 — 51 pF, 100 Mil Chip Capacitor

C2, C13 — 15

µF, 20 WV Tantalum

C3, C12 — 1000 pF Unelco J101

C4, C10 — 91 pF Mini–Underwood

C5 — 15 pF Mini–Underwood

C6 — 12 pF Mini–Underwood

C7, C8 — 21 pF Mini–Underwood

C9 — 11 pF Mini–Underwood

L1, L4 — 11 Turns #20 AWG Over 10 ohm 1/2 W Carbon

L2, L3 — 4 Turns #20 AWG, 200 Mil ID

TL1, TL4 — Micro Strip, Zo = 50 Ω

TL2 — Micro Strip, Zo = 38 Ω, λ/4 @ 838 MHz

TL3 — Micro Strip, Zo = 24 Ω, λ/4 @ 838 MHz

Board — 0.032

″ Glass Teflon

εr = 2.55

C2

L4

C3

L1

L2

C12

C13

B

B

C1

C11

TL4

C9

C6

L3

C4

C10

TL3

TL2

TL1

+12.5 Vdc

VRE

PORT

C5

C7

C8

D.U.T.

+

+

SOCKET

SOCKET