1
MRF857S
MOTOROLA RF DEVICE DATA
The RF Line
Designed for 24 Volt UHF large
signal, common emitter, class A linear
amplifier applications in industrial and commercial equipment operating in the
range of 800
960 MHz.
Specified for VCE = 24 Vdc, IC = 0.3 Adc Characteristics
Output Power = 2.1 Watts CW
Minimum Power Gain = 12.5 dB
Minimum ITO = + 43 dBm
Typical Noise Figure = 5.25 dB
Characterized with Small
Signal S
Parameters and Series Equivalent
Large
Signal Parameters from 800
960 MHz
Silicon Nitride Passivated
100% Tested for Load Mismatch Stress at All Phase Angles with 30:1
VSWR @ 24 Vdc, IC = 0.3 Adc and Rated Output Power
Will Withstand RF Input Overdrive of 0.4 W CW
Gold Metallized, Emitter Ballasted for Long Life and Resistance to Metal
Migration
Circuit board photomaster available upon request by contacting
RF Tactical Marketing in Phoenix, AZ.
MAXIMUM RATINGS
Rating
Symbol
Value
Unit
Collector
Emitter Voltage
VCEO
30
Vdc
Collector
Base Voltage
VCBO
55
Vdc
Emitter
Base Voltage
VEBO
4
Vdc
Total Device Dissipation @ TC = 50 C
Derate above 50 C
PD
17
0.114
Watts
W/ C
Operating Junction Temperature
TJ
200
C
Storage Temperature Range
Tstg
65 to +150
C
THERMAL CHARACTERISTICS
Characteristic
Symbol
Max
Unit
Thermal Resistance (TJ = 150 C, TC = 50 C)
R JC
8.4
C/W
ELECTRICAL CHARACTERISTICS
Characteristic
Symbol
Min
Typ
Max
Unit
OFF CHARACTERISTICS
Collector
Emitter Breakdown Voltage (IC = 20 mA, IB = 0)
V(BR)CEO
28
35
--
Vdc
Collector
Emitter Breakdown Voltage (IC = 20 mA, VBE = 0)
V(BR)CES
55
85
--
Vdc
Collector
Base Breakdown Voltage (IC = 20 mA, IE = 0)
V(BR)CBO
55
85
--
Vdc
Emitter
Base Breakdown Voltage (IE = 1 mA, IC = 0)
V(BR)EBO
4
5
--
Vdc
Collector Cutoff Current (VCB = 24 V, IE = 0)
ICES
--
--
1
mA
(continued)
Order this document
by MRF857/D
SEMICONDUCTOR TECHNICAL DATA
CLASS A
800
960 MHz
2.1 W (CW), 24 V
NPN SILICON
RF POWER TRANSISTOR
CASE 305D
01, STYLE 1
Motorola, Inc. 1997
REV 3
MRF857S
2
MOTOROLA RF DEVICE DATA
ELECTRICAL CHARACTERISTICS
--
continued
Characteristic
Symbol
Min
Typ
Max
Unit
ON CHARACTERISTICS
DC Current Gain
(IC = 0.1 A, VCE = 5 V)
hFE
30
60
120
--
DYNAMIC CHARACTERISTICS
Output Capacitance
(VCB = 24 V, f = 1 MHz)
Cob
2.4
3.3
4.4
pF
FUNCTIONAL CHARACTERISTICS
Common
Emitter Power Gain
(VCE = 24 V, IC = 0.3 A, f = 840
900 MHz,
Power Output = 2.1 W)
Pg
12.5
13.5
--
dB
Load Mismatch
(Po = 2.1 W)
(VCE = 24 V, IC = 0.3 A, f = 840 MHz,
Load VSWR = 30:1, All Phase Angles)
No Degradation in
Output Power
RF Input Overdrive
(VCE = 24 V, IC = 0.3 A, f = 840 MHz)
No degradation
Pin(over)
--
--
0.4
W
Third Order Intercept Point
(VCE = 24 V, IC = 0.3 A)
(f1 = 900 MHz, f2 = 900.1 MHz,
Meas. @ IMD 3rd Order =
40 dBc)
ITO
+ 43
+ 44.5
--
dBm
Noise Figure
(VCE = 24 V, IC = 0.3 A, f = 900 MHz)
NF
--
5.25
--
dB
Input Return Loss
(VCE = 24 V, IC = 0.3 A, f = 840
900 MHz,
Power Output = 2.1 W)
IRL
--
15
10
dB
Table 1. MRF857S Common Emitter S
Parameters
VCE
IC
f
S11
S21
S12
S22
VCE
(V)
IC
(A)
f
(MHz)
|S11|
|S21|
|S12|
|S22|
24
0.3
800
820
840
860
880
900
920
940
960
0.915
0.915
0.915
0.913
0.914
0.914
0.913
0.915
0.916
165
165
165
164
164
163
163
162
162
2.098
2.049
1.991
1.951
1.912
1.865
1.832
1.783
1.748
54
53
52
51
50
49
48
47
46
0.037
0.038
0.038
0.039
0.040
0.041
0.042
0.043
0.043
58
58
58
59
59
59
59
59
59
0.343
0.345
0.349
0.352
0.355
0.359
0.362
0.366
0.369
157
157
157
158
158
158
158
159
159
Table 2. Zin and ZOL* versus Frequency
f
(MHz)
Zin
(Ohms)
ZOL*
(Ohms)
840
870
900
1.5
1.7
1.5
4.4
4.7
4.8
18.4
18.0
14.9
26.3
26.1
26.2
VCE = 24 V, IC = 0.3 A, Po = 2.1 W
ZOL* = Conjugate of optimum load impedance into which the device operates at a given output power, voltage and frequency.
3
MRF857S
MOTOROLA RF DEVICE DATA
B1, B4
Long Ferrite Bead, Fair Rite (2743021447)
B2, B3
Short Ferrite Bead, Fair Rite (2743019447)
C1
250 F, 50 Vdc Electrolytic Capacitor
C2, C8
10 F, 50 Vdc Electrolytic Capacitor
C3, C9
0.1 F, Chip Capacitor
C4, C7
1000 pF, Chip Capacitor
C5, C6
100 pF, Chip Capacitor
C10, C12
43 pF, 100 Mil Chip Capacitor
C11
0.8
8 pF, Johansen Gigatrim
F1
1 A Micro
Fuse
L1, L2
5 Turns, 20 AWG, 0.126 ID, 46.2 nH
Q1
MMBT2222ALT1, NPN Transistor
Q2
BD136, PNP Transistor
R1
330 , 1/4 W
R2
500 Potentiometer, 1/4 W
R3
4.7K , 1/4 W
R4
2 x 4.7K , 1/4 W
R5
47 , 2 W
R6
75 , 1/4 W
R7
4.7 , 1/4 W
R8
10 , 3 W
R9, R10
4 x 39 , 1/8 W Chip Resistors in Parallel
TL1
TL16
Microstrip Transmission Line
V_Supply
+ 27 Vdc 0.5 V Due to Resistor Tolerance
VCE
+ 24 Vdc @ 0.3 A
Board
0.030 Glass
Teflon 2 oz. Cu, r = 2.55
Figure 1. MRF857S Class A RF Test Fixture Schematic
R1
Q1
VCE
R2
R3
Q2
R4
R5
R6
C7
R9
R10
B3
B4
B1
TL6
TL5
TL4
C10
TL1
TL7
TL8
DUT
TL10
TL13
C12
TL16
R7
C8
+
C9
C4
C5
B2
R8
C1
+
V_SUPPLY
OUTPUT
INPUT
TL2
TL3
TL9
L1
C6
L2
TL11
TL12
TL14
TL15
C2
C3
+
C11
F1
MRF857S
4
MOTOROLA RF DEVICE DATA
15
14.5
14
830
910
f, FREQUENCY (MHz)
Figure 2. Performance of MRF857S in
Broadband Circuit
TYPICAL CHARACTERISTICS
13.5
13
12.5
12
840
850
860
870
880
890
900
Gpe
4
3.5
3
2.5
2
1.5
1
VSWR
VCC = 24 Vdc
IC = 300 mA
Pout = 2.1 W (CW)
4
3.5
3
0
Pin, INPUT POWER (WATTS)
Figure 3. MRF857S Output Power & Power Gain
versus Input Power
2.5
2
1.5
0
0.05
0.1
0.15
0.2
Gpe
16
15
14
13
12
11
8
Pout
VCC = 24 Vdc
IC = 300 mA
f = 870 MHz
1
0.5
0.25
0.3
0.35
0.4
10
9
1500
0
VCE (Vdc)
Figure 4. MRF857S DC SOA
0
Tj = 150 C
Tf = 50 C
1000
500
850
0
VCE (Vdc)
Figure 5. MRF857S DC SOA
(This device is MTBF limited for VCE 20 Vdc.)
50
0
Tj = 175 C
Tf = 50 C
800
750
700
650
600
550
1.00E+08
100
TJ, JUNCTION TEMPERATURE ( C)
Figure 6. MRF857S MTBF Factor versus
Junction Temperature
1.00E+07
1.00E+06
1.00E+05
1.00E+04
1.00E+03
1.00E+02
120
140
160
180
200
220
240
260
2
4
6
8
10 12 14 16 18 20 22 24 26 28
2
4
6
8
10 12 14 16 18 20 22 24 26 28
9.80E+06
2.01E+06
4.82E+05
1.32E+05
4.03E+04
1.37E+04
5.05E+03
8.67E+02
2.02E+03
5
MRF857S
MOTOROLA RF DEVICE DATA
Figure 7. MRF857S Test Fixture Component Layout
MRF857S
C11
C12
C1
Q2
C9
C7
C10
C2
C3
L2
C6
B3
B4
R10
+
R8
C8
+
R9
B1
R7
C5
C4
B2
R4
L1
R5
R3
R2
R1
Q1
R6
+
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