Datasheet LFE18500X Datasheet (Philips)

DISCRETE SEMICONDUCTORS

DATA SH EET

LFE18500X

NPN silicon planar epitaxial
microwave power transistor

Product specification
File under Discrete Semiconductors, SC15

Philips Semiconductors

December 1994

Philips Semiconductors Product specification

NPN silicon planar epitaxial
microwave power transistor

FEATURES

• Diffused emitter ballasting resistors
providing excellent current sharing
and withstanding a high VSWR

• Interdigitated structure provides
high emitter efficiency

• Gold metallization realizes very
good stability of the characteristics
and excellent lifetime

• Multicell geometry gives good
balance of dissipated power and
low thermal resistance

• Internal input and output
prematching ensures good stability
and allows an easier design of
wideband circuits.

APPLICATION

Intended for use in common emitter,
class AB amplifiers in CW conditions
for professional applications between

1.8 GHz and 1.9 GHz.

DESCRIPTION

NPN silicon planar epitaxial
microwave power transistor in a
FO-231 glued cap metal ceramic
flange package, with emitter
connected to flange.

QUICK REFERENCE DATA

Microwave performance up to T

=25°C in a common emitter class AB

mb

amplifier.

MODE OF

OPERATIONf(GHz)

Class AB

1.85 24 0.2 ≥48 ≥7 typ. 42 see Figs 7

V

(V)

CE

I

CQ

(A)

(CW)

PINNING - FO-231

PIN DESCRIPTION

1 collector
2 base
3 emitter connected to flange

handbook, 4 columns

Top view

1

2

Fig.1 Simplified outline and symbol.

33

P

L1

(W)

G

po

(dB)

MAM045 - 1

LFE18500X

η

C

(%)

b

Zi;Z

(Ω)

and 8

c

e

L

WARNING

Product and environmental safety - toxic materials

This product contains beryllium oxide. The product is entirely safe provided that the BeO slab is not damaged.
All persons who handle, use or dispose of this product should be aware of its nature and of the necessary safety
precautions. After use, dispose of as chemical or special waste according to the regulations applying at the location of
the user. It must never be thrown out with the general or domestic waste.

December 1994 2

Philips Semiconductors Product specification

NPN silicon planar epitaxial

LFE18500X

microwave power transistor

LIMITING VALUES

In accordance with the Absolute Maximum Rating System (IEC 134).

SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT

V

CBO

V

CER

V

CEO

V

EBO

I

C

P

i

P

tot

T

stg

T

j

T

sld

Note

1. Up to 0.2 mm from ceramic.

collector-base voltage open emitter − 45 V
collector-emitter voltage RBE= 220 Ω−30 V
collector-emitter voltage open base − 22 V
emitter-base voltage open collector − 3V
DC collector current − 12 A
input power f = 1.85 GHz; VCE= 24 V; class AB − 20 W
total power dissipation Tmb=75°C − 120 W
storage temperature −65 +200 °C
junction temperature − 200 °C
soldering temperature t ≤ 10 s; note 1 − 235 °C

160

handbook, halfpage

P

tot

(W)

120

80

40

0

0 50 100 200

150

T ( C)

Fig.2 Power derating curve.

mb

MLC430

o

December 1994 3

Philips Semiconductors Product specification

NPN silicon planar epitaxial

LFE18500X

microwave power transistor

THERMAL CHARACTERISTICS

SYMBOL PARAMETER CONDITIONS MAX. UNIT

R

th j-mb

R

th mb-h

CHARACTERISTICS

=25°C unless otherwise specified.

T

mb

SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT

I

CBO

V

(BR)CER

V

(BR)CBO

V

(BR)EBO

h

FE

APPLICATION INFORMATION

Microwave performance up to T

thermal resistance from junction to mounting base Tj= 100 °C 1 K/W
thermal resistance from mounting base to heatsink 0.2 K/W

collector cut-off current IE= 0; VCB=20V − 6mA
collector-emitter breakdown voltage IC= 30 mA; RBE=56Ω 30 − V
collector-base breakdown voltage IC=30mA 45 − V
emitter-base breakdown voltage IE=30mA 3 − V
DC current gain IC= 1 A; VCE= 5 V 15 100

=25°C in a common emitter class AB amplifier.

mb

MODE OF

OPERATION

f

(GHz)

V

(V)

CE

I

CQ

(A)

P

L1

(W)

Class AB (CW) 1.85 24 0.2 ≥48

typ. 53

G

po

(dB)

≥7

typ. 7.5

η

(%)

C

Zi; Z

(Ω)

L

typ. 42 see Figs 7

and 8

December 1994 4

Philips Semiconductors Product specification

NPN silicon planar epitaxial
microwave power transistor

handbook, full pagewidth

6.0

2.0

5.2

40

2.0

LFE18500X

30

1.5

4.0

4.0

1.5

7.0

2.0

3.0

4.0

3.02.0

5.07.0

3.5

30

15.2

1.0

2.0

40

0.6950.695

1.0

2.0

V

C5

F1

input

C1

The test circuit is split into two independent halves, each being 30 x40 mm in size.
Dimensions in mm.
Substrate: Epsilam 10.
Thickness: 0.635 mm.
Permittivity: εr= 10.

BB

L1

C2

V

C6

L2

C3

CC

C7

output

C4

MLC434

Fig.3 Prematching test circuit board.

December 1994 5

Philips Semiconductors Product specification

NPN silicon planar epitaxial
microwave power transistor

handbook, full pagewidth

R1

R2

P1

BIAS CIRCUIT

TR1

D1

D2

LFE18500X

PREMATCHING TEST

CIRCUIT

V

CC

F1

C6

L2

DUT

MEA600

C5

C7R3

L1

Fig.4 Class AB bias circuit.

List of components (see Figs 3 and 4)

COMPONENT DESCRIPTION VALUE ORDERING INFORMATION

TR1 transistor, BDT91 or equivalent
C1, C4 DC blocking chip capacitor 100 pF ATC 100A101kp
C2, C3 trimmer capacitor 0.5 to 5.0 pF Tekelec 727-1
C5, C6 feedthrough bypass capacitor 1500 pF Erie 1250-003
C7 electrolytic capacitor 10 µF, 50 V
D1 diode BY239 or equivalent; note 1
D2 diode BY239 or equivalent; note 2
L1 4 turns 0.5 mm copper wire;

internal diameter = 2 mm

L2 3 turns 0.5 mm copper wire;

internal diameter = 2 mm
P1 linear potentiometer 4.7 kΩ
R1 resistor 100 Ω, 0.25 W
R2 resistor 10 kΩ, 0.25 W
R3 resistor 56 Ω, 0.25 W
F1 ferrite bead Philips tube, 12NC = 4330 030 43081

4.2 x 2.2 x 3.2 mm (4B1)

Notes

1. In thermal contact with TR1.

2. In thermal contact with DUT.

December 1994 6

Philips Semiconductors Product specification

NPN silicon planar epitaxial
microwave power transistor

60

handbook, halfpage

P

L

(W)

40

I =

CQ

20

0

04 81216

400 mA
200 mA
100 mA

MLC431

P (W)

i

20

handbook, halfpage

d

im

(dBc)

I =

100 mA

30

200 mA

40

400 mA

50

60

01020 40

CQ

LFE18500X

MLC726

30

P (W)

o (av)

VCE= 24 V; f1= 1849.9 MHz; f2= 1850.1 MHz.

VCE= 24 V; f = 1850 MHz.

Fig.6 Intermodulation distortion as a function

Fig.5 Load power as a function of input power.

Input and optimum load impedances

V

=24V; ICQ= 0.2 A; Zo=10Ω; typical values at PL=PL1 (see Figs 7 and 8).

CE

f

(GHz)

Z

(Ω)

i

1.80 5.0 + j4.9 2.0 − j2.0

1.85 5.5 + j2.0 1.8 − j1.2

1.90 3.7 + j0.6 1.6 − j1.6

of average output power.

Z

(Ω)

L

December 1994 7

Philips Semiconductors Product specification

NPN silicon planar epitaxial
microwave power transistor

handbook, full pagewidth

0.2

+ j

0

– j

0.2

VCE= 24 V; Zo=10Ω; ICQ= 0.2 A.

0.5

0.2

0.5

1.9 GHz

Z

1.8 GHz

i

0.5

1

1.85 GHz

1

LFE18500X

2

5

10

1052

∞

10

5

2

MLC432

Fig.7 Input impedance as a function of frequency; typical values at PL=PL1.

handbook, full pagewidth

VCE= 24 V; Zo=10Ω; ICQ= 0.2 A.

1

0.5

0.2

+ j

0

– j

0.2

0.2 0.5 1052

1.85 GHz

Z

L

1.9 GHz

1.8 GHz

0.5

1

2

5

10

∞

10

5

2

MLC433

Fig.8 Optimum load impedance as a function of frequency; typical values at PL=PL1.

December 1994 8

Philips Semiconductors Product specification

NPN silicon planar epitaxial
microwave power transistor

PACKAGE OUTLINE

0.15 max

3.3

2.9

3.3

seating plane

15.5 max

26 max

3.7

max

LFE18500X

6

max

1.6 max

3

9.85
max

2.7
min

10.3

10.0

1

Dimensions in mm.
Torque on screws: max. 0.5 Nm.
Recommended screw: M3.

10.15

20.3

Fig.9 FO-231.

33

MSA376

2.7
min

2

December 1994 9

Philips Semiconductors Product specification

NPN silicon planar epitaxial

LFE18500X

microwave power transistor

DEFINITIONS

Data Sheet Status

Objective specification This data sheet contains target or goal specifications for product development.
Preliminary specification This data sheet contains preliminary data; supplementary data may be published later.
Product specification This data sheet contains final product specifications.

Limiting values

Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or
more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation
of the device at these or at any other conditions above those given in the Characteristics sections of the specification
is not implied. Exposure to limiting values for extended periods may affect device reliability.

Application information

Where application information is given, it is advisory and does not form part of the specification.

LIFE SUPPORT APPLICATIONS

These products are not designed for use in life support appliances, devices, or systems where malfunction of these
products can reasonably be expected to result in personal injury. Philips customers using or selling these products for
use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting from such
improper use or sale.

December 1994 10