Philips BLF278 User Guide

DISCRETE SEMICONDUCTORS

DATA SH EET

M3D091

BLF278

VHF push-pull power MOS
transistor

Product Specification
Supersedes data of 1996 Oct 21

2003 Sep 19

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

FEATURES

• High power gain

• Easy power control

• Good thermal stability

• Gold metallization ensures excellent reliability.

APPLICATIONS

• Broadcast transmitters in the VHF frequency range.

DESCRIPTION

Dual push-pull silicon N-channel enhancement mode
vertical D-MOS transistor encapsulated in a 4-lead,
SOT262A1 balanced flange package with two ceramic
caps. The mounting flange provides the common source
connection for the transistors.

CAUTION

This productis supplied in anti-static packing to prevent
damage caused by electrostatic discharge during
transport and handling. For further information, refer to
Philips specs.: SNW-EQ-608, SNW-FQ-302A, and
SNW-FQ-302B.

PINNING - SOT262A1

PIN DESCRIPTION

1 drain 1
2 drain 2
3 gate 1
4 gate 2
5 source

12

55

34

Top view

Fig.1 Simplified outline and symbol.

d

g

s

g

d

MAM098

QUICK REFERENCE DATA

RF performance at Th=25°C in a push-pull common source test circuit.

MODE OF OPERATION

f

(MHz)

V

(V)

DS

P

(W)

L

G

(dB)

p

η

D

(%)

CW, class-B 108 50 300 >20 >60
CW, class-C 108 50 300 typ. 18 typ. 80
CW, class-AB 225 50 250 >14

typ. 16

>50

typ. 55

WARNING

Product and environmental safety - toxic materials

This product contains beryllium oxide. The product is entirely safe provided that the BeO discs are 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.

2003 Sep 19 2

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

LIMITING VALUES

In accordance with the Absolute Maximum System (IEC 60134).

SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT

Per transistor section

V

DS

V

GS

I

D

P

tot

T

stg

T

j

THERMAL CHARACTERISTICS

SYMBOL PARAMETER CONDITIONS VALUE UNIT

R

th j-mb

R

th mb-h

drain-source voltage − 125 V
gate-source voltage −±20 V
drain current (DC) − 18 A
total power dissipation Tmb≤ 25 °C; total device; both

− 500 W

sections equally loaded
storage temperature −65 150 °C
junction temperature − 200 °C

thermal resistance from junction
to mounting base

thermal resistance from
mounting base to heatsink

total device; both sections

equally loaded.

total device; both sections

equally loaded.

max. 0.35 K/W

max. 0.15 K/W

100

handbook, halfpage

I

D

(A)

(1)

10

1

1 10 100

Total device; both sections equally loaded.
(1) Current is this area may be limited by R
(2) Tmb=25°C.

Fig.2 DC SOAR.

(2)

DSon

MRA988

V (V)

DS

.

500

500

handbook, halfpage

P

tot

(W)

400

300

200

100

0

0 40 80 160

Total device; both sections equally loaded.
(1) Continuous operation.
(2) Short-time operation during mismatch.

(1)

Fig.3 Power derating curves.

(2)

120

MGE616

Th (°C)

2003 Sep 19 3

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

CHARACTERISTICS

Tj=25°C unless otherwise specified.

SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT

Per transistor section

V

(BR)DSS

I

DSS

I

GSS

V

GSth

∆V

GS

g

fs

g

fs1/gfs2

R

DSon

I

DSX

C

is

C

os

C

rs

C

d-f

drain-source breakdown voltage VGS= 0; ID= 100 mA 125 −−V
drain-source leakage current VGS= 0; VDS=50V −−2.5 mA
gate-source leakage current VGS= ±20 V; VDS=0 −−1µA
gate-source threshold voltage VDS= 10 V; ID=50mA 2 − 4.5 V
gate-source voltage difference

VDS= 10 V; ID=50mA −−100 mV
of both sections

forward transconductance VDS= 10 V; ID= 5 A 4.5 6.2 − S
forward transconductance ratio

VDS= 10 V; ID=5A 0.9 − 1.1
of both sections

drain-source on-state resistance VGS= 10 V; ID=5A − 0.2 0.3 Ω
drain cut-off current VGS= 10 V; VDS=10V − 25 − A
input capacitance VGS= 0; VDS= 50 V; f = 1 MHz − 480 − pF
output capacitance VGS= 0; VDS= 50 V; f = 1 MHz − 190 − pF
feedback capacitance VGS= 0; VDS= 50 V; f = 1 MHz − 14 − pF
drain-flange capacitance − 5.4 − pF

VGS group indicator

GROUP

A 2.0 2.1 O 3.3 3.4
B 2.1 2.2 P 3.4 3.5
C 2.2 2.3 Q 3.5 3.6
D 2.3 2.4 R 3.6 3.7
E 2.4 2.5 S 3.7 3.8
F 2.5 2.6 T 3.8 3.9
G 2.6 2.7 U 3.9 4.0
H 2.7 2.8 V 4.0 4.1

J 2.8 2.9 W 4.1 4.2
K 2.9 3.0 X 4.2 4.3
L 3.0 3.1 Y 4.3 4.4

M 3.1 3.2 Z 4.4 4.5
N 3.2 3.3

LIMITS

(V)

GROUP

LIMITS

(V)

MIN. MAX. MIN. MAX.

2003 Sep 19 4

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

handbook, halfpage

0

T.C.

(mV/K)

−1

−2

−3

−4

−5

10

VDS=10V.

−2

−1

10

110

ID (A)

Fig.4 Temperature coefficient of gate-source

voltageasafunctionofdraincurrent;typical
values per section.

MGE623

30

handbook, halfpage

I

D

(A)

20

10

0

0

VDS= 10 V; Tj=25°C.

5

10

MGE622

VGS (V)

Fig.5 Drain current as a function of gate-source

voltage; typical values per section.

15

400

handbook, halfpage

R

DSon

(mΩ)

300

200

100

0

0 50 100 150

VGS= 10 V; ID=5A.

Tj (°C)

Fig.6 Drain-source on-state resistance as a

function of junction temperature; typical
values per section.

MGE621

C

is

C

os

VDS (V)

MGE615

1200

handbook, halfpage

C

(pF)

800

400

0

0

VGS= 0; f = 1 MHz.

20

40

Fig.7 Input and output capacitance as functions

of drain-source voltage; typical values per
section.

60

2003 Sep 19 5

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

400

handbook, halfpage

C

rs

(pF)

300

200

100

0

010 50

VGS= 0; f = 1 MHz.

20 30 40

VDS (V)

Fig.8 Feedback capacitance as a function of

drain-source voltage; typical values per
section.

MGE620

APPLICATION INFORMATION
Class-B operation

RF performance in CW operation in a common source push-pull test circuit. Th=25°C; R
otherwise specified. R

MODE OF OPERATION

=4Ω per section; optimum load impedance per section = 3.2 + j4.3 Ω (VDS= 50 V).

GS

f

(MHz)

V

(V)

DS

I

DQ

(A)

P

(W)

L

CW, class-B 108 50 2 × 0.1 300 >20

= 0.15 K/W unless

th mb-h

G

p

(dB)

typ. 22

η

D

(%)

>60

typ. 70

CW, class-C 108 50 VGS= 0 300 typ. 18 typ. 80

Ruggedness in class-B operation

The BLF278 is capable of withstanding a load mismatch corresponding to VSWR = 7:1 through all phases under the
following conditions: V

= 50 V; f = 108 MHz at rated load power.

DS

2003 Sep 19 6

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

30

handbook, halfpage

G

p

(dB)

20

10

0

0

Class-B operation; VDS=50V;IDQ=2×0.1 A; f = 108 MHz;

= 3.2 + j4.3 Ω (per section); RGS=4Ω (per section).

Z

L

(1) Th=25°C.
(2) Th=70°C.

(1)

(2)

200 400 600

MGE682

PL (W)

Fig.9 Power gain as a function of load power;

typical values.

80

handbook, halfpage

η

D

(%)

60

(1)

40

20

0

0 200 400

Class-B operation; VDS=50V;IDQ=2×0.1 A; f = 108 MHz;

= 3.2 + j4.3 Ω (per section); RGS=4Ω (per section).

Z

L

(1) Th=25°C.
(2) Th=70°C.

(2)

(2)

(1)

PL (W)

Fig.10 Efficiency as a function of load power;

typical values.

MGE683

600

600

handbook, halfpage

P

L

(W)

400

200

0

0

Class-B operation; VDS=50V;IDQ=2×0.1 A; f = 108 MHz;

= 3.2 + j4.3 Ω (per section); RGS=4Ω (per section).

Z

L

(1) Th=25°C.
(2) Th=70°C.

(1)

(2)

51015

MGE684

Pi (W)

Fig.11 Load power as a function of input power;

typical values.

2003 Sep 19 7

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2003 Sep 19 8

+V

handbook, full pagewidth

R2

DD1

C20

C16

C21

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

50 Ω
input

+V

DD1

T1

R11

C1

C2

C36

R1

C3

C4

IC1

A

A

C8

L1

C5

L2

C35

C37

R3

C9

R4

L3 L5 L7

C6 C7

L4 L6 L8

C10

R6

R7

C11

C12

C13

R5

C14

C15

D.U.T.

C17

L12

L9

C26

C27

L14 L18 L20

L10

L15

C18

R9 L16

C19

C22

C28

C23

C24

C25

L11R8

L19L17L13

C29 C30

C31

C32

C33

R10

C34

L21

50 Ω
output

L22

L23

MGE688

+V

DD2

Fig.12 Class-B test circuit at f = 108 MHz.

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

List of components (see Figs 12 and 13).

COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO.

C1, C2, C33, C34 multilayer ceramic chip capacitor;

note 1

C3, C4 multilayer ceramic chip capacitor;

note 1
C5, C6, C28 film dielectric trimmer 5 to 60 pF 2222 809 08003
C7 multilayer ceramic chip capacitor;

note 1

C8, C11, C12,
C15, C16, C19,
C36

C9, C10, C13,
C14, C20, C25

C17, C18, C22,
C23

C21, C24, C35 electrolytic capacitor 10 µF, 63 V
C26 multilayer ceramic chip capacitor;

C27 multilayer ceramic chip capacitor;

C29 multilayer ceramic chip capacitor;

C30 film dielectric trimmer 2 to 18 pF 2222 809 09006
C31, C32 multilayer ceramic chip capacitor;

L1, L2 stripline; note 2 43 Ω length 57.5 mm

L3, L4 stripline; note 2 43 Ω length 29.5 mm

L5, L6 stripline; note 2 43 Ω length 14 mm

L7, L8 stripline; note 2 43 Ω length 6 mm

L9, L10 stripline; note 2 43 Ω length 17.5 mm

L11, L16 2 × grade 3B Ferroxcube wideband

L12, L15 4 turns enamelled 2 mm copper wire 85 nH length 13.5 mm

L13, L14 stripline; note 2 43 Ω length 19.5 mm

multilayer ceramic chip capacitor 100 nF, 500 V 2222 852 47104

multilayer ceramic chip capacitor;

note 1

multilayer ceramic chip capacitor;

note 1

note 1

note 1

note 1

note 1

HF chokes in parallel

22 pF, 500 V

100pF+68pF
in parallel, 500 V

2 × 100 pF +
1 × 120 pF in
parallel, 500 V

1 nF, 500 V

470 pF, 500 V

2 × 15 pF +
1 × 18 pF in
parallel, 500 V

3 × 15 pF in
parallel, 500 V

2 × 18 pF +
1 × 15 pF in
parallel, 500 V

3 × 43 pF in
parallel, 500 V

width 6 mm

width 6 mm

width 6 mm

width 6 mm

width 6 mm

4312 020 36642

int. dia. 10 mm
leads 2 × 7mm

width 6 mm

2003 Sep 19 9

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO.

L17, L18 stripline; note 2 43 Ω length 24.5 mm

width 6 mm

L19, L20 stripline; note 2 43 Ω length 66 mm

width 6 mm

L21, L23 stripline; note 2 50 Ω length 160 mm

width 4.8 mm

L22 semi-rigid cable; note 3 50 Ω ext. dia. 3.6 mm

outer conductor

length 160 mm
R1 metal film resistor 10 Ω, 0.4 W
R2, R7 10 turn potentiometer 50 kΩ
R3, R6 metal film resistor 3 × 12.1 Ω in

parallel, 0.4 W
R4, R5 metal film resistor 10 Ω; 0.4 W
R8, R9 metal film resistor 10 Ω±5%, 1 W
R10 metal film resistor 4 × 10 Ω in

parallel, 1 W
R11 metal film resistor 5.11 kΩ, 1W
IC1 voltage regulator 78L05
T1 1:1 Balun; 7 turns type 4C6 50 Ω

coaxial cable wound around toroid

14 × 9 × 5 mm 4322 020 90770

Notes

1. American Technical Ceramics capacitor, type 100B or capacitor of same quality.

2. L1 to L10, L13, L14, L17 to L21 and L23 are striplines on a double copper-clad printed-circuit board, with fibre-glass
PTFE dielectric (εr= 2.2), thickness1⁄16inch; thickness of copper sheet 2 × 35 µm.

3. L22 is soldered on to stripline L21.

2003 Sep 19 10

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

handbook, full pagewidth

strap

strap

50 Ω
input

C3

R1

C2C1C4

strap

strap

C28

150

L21

L19
L20

L23

L22

C29

C30

C31

C32

C34

MBC438

strap

strap

C33

R10

100

50 Ω
output

130

strap

strap

C20

V

DD1

T1

C5

R11

L1
L2

IC1

C36

slider R2

C6

slider R7

C8

C12

L3
L4

C15

C11

R2 and R7

C7

C35

C9

R3

R4

L5
L6L7L8

R5

R6

C10

C14

C13

L11

C22

C17

L9

L10

C18

C23 C24

C16

R8
L11

V

L12

L13

C26 C27

L14

L15

V

L16
R9

C19

L16

C21

DD1

L17
L18

DD2

C25

Dimensions in mm.

The circuit and components are situated on one side of the PTFE fibre-glass board, the other side being fully metallized to serve as an earth.
Earth connections are made by means of copper straps for a direct contact between upper and lower sheets.

Fig.13 Printed-circuit board and component layout for 108 MHz class-B test circuit.

2003 Sep 19 11

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

handbook, halfpage

2

Z

i

(Ω)

1

0

−1

−2

25 75 125

Class-B operation; VDS= 50 V; IDQ=2×0.1 A;

=4Ω (per section); PL= 300 W.

R

GS

r

i

x

i

MGE685

f (MHz)

Fig.14 Input impedance as a function of frequency

(series components); typical values per
section.

175

8

handbook, halfpage

Z

L

(Ω)

6

4

2

0

25 75 125

Class-B operation; VDS= 50 V; IDQ=2×0.1 A;

=4Ω (per section); PL= 300 W.

R

GS

R

L

X

L

MGE686

f (MHz)

Fig.15 Load impedance as a function of frequency

(series components); typical values per
section.

175

handbook, halfpage

Fig.16 Definition of MOS impedance.

30

handbook, halfpage

G

p

(dB)

20

10

Z

i

Z

MBA379

L

0

25

Class-B operation; VDS= 50 V; IDQ=2×0.1 A;

=4Ω (per section); PL= 300 W.

R

GS

75 125 175

MGE687

f (MHz)

Fig.17 Power gain as a function of frequency;

typical values per section.

2003 Sep 19 12

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

Class-AB operation

RF performance in CW operation in a common source push-pull test circuit. Th=25°C; R
otherwise specified. R

= 2.8 Ω per section; optimum load impedance per section = 0.74 + j2 Ω; (VDS= 50 V).

GS

= 0.15 K/W unless

th mb-h

MODE OF OPERATION

f

(MHz)

CW, class-AB 225 50 2 × 0.5 250 >14

V

(V)

DS

I

DQ

(A)

P

(W)

L

G

p

(dB)

η

(%)

D

>50

typ. 16

typ. 55

Ruggedness in class-AB operation

The BLF278 is capable of withstanding a load mismatch corresponding to VSWR = 7:1 through all phases under the
following conditions: V

= 50 V; f = 225 MHz at rated output power.

DS

2003 Sep 19 13

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

20

handbook, halfpage

G

p

(dB)

10

0

0 100 200 300

Class-AB operation; VDS= 50 V; IDQ=2×0.5 A; f = 225 MHz;

= 0.74 + j2 Ω (per section); RGS= 2.8 Ω (per section).

Z

L

(1) Th=25°C.
(2) Th=70°C.

(1)

(2)

PL (W)

Fig.18 Power gain as a function of load power;

typical values.

MGE614

60

handbook, halfpage

η

D

(%)

40

20

0

0

Class-AB operation; VDS= 50 V; IDQ=2×0.5 A; f = 225 MHz;

= 0.74 + j2 Ω (per section); RGS= 2.8 Ω (per section).

Z

L

(1) Th=25°C.
(2) Th=70°C.

(1)

(2)

100 200

PL (W)

Fig.19 Efficiency as a function of load power;

typical values.

MGE612

300

400

handbook, halfpage

P

L

(W)

300

(1)

200

100

0

0 5 10 15

Class-AB operation; VDS= 50 V; IDQ=2×0.5 A; f = 225 MHz;

= 0.74 + j2 Ω (per section); RGS= 2.8 Ω (per section).

Z

L

(1) Th=25°C.
(2) Th=70°C.

(2)

MGE613

Pi (W)

Fig.20 Load power as a function of input power;

typical values.

2003 Sep 19 14

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2003 Sep 19 15

R2

handbook, full pagewidth

+V

DD1

C22

C14

C23

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

50 Ω
input

+V

L2

DD1

L14R8

C24

L15

L20L18L12

C21 C28 C29 C30

L19 L21

L16

C25

L17

C26

C27

C31

C32

R10

C33

C34

L22

L24

L23

MGE617

50 Ω
output

R3

C8

R4

L6 L8 L10

C6 C7

L7 L9 L11

C9

R6

R7

C36

R5

C10

C11

C12

C13

C15

C16

D.U.T.

C20

L13

C17

C18

R9

C19

A

C1

C2

C38

R1

C3

C4

IC1

L4

C5

L5L3

A

C35

C37

L1

R11

+V

DD2

Fig.21 Class-AB test circuit at f = 225 MHz.

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

List of components (see Figs 21 and 22).

COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO.

C1, C2 multilayer ceramic chip capacitor;

note 1

C3, C4, C31, C32 multilayer ceramic chip capacitor;

note 1
C5 film dielectric trimmer 4 to 40 pF 2222 809 08002
C6, C30 film dielectric trimmer 2 to 18 pF 2222 809 09006
C7 multilayer ceramic chip capacitor;

note 1
C8, C9, C15, C18 MKT film capacitor 1 µF, 63 V 2222 371 11105
C10, C13, C14,

C19, C36
C11, C12 multilayer ceramic chip capacitor;

C16, C17 electrolytic capacitor 220 µF, 63 V
C20 multilayer ceramic chip capacitor;

C21 film dielectric trimmer 2 to 9 pF 2222 809 09005
C22, C27, C37,

C38
C23, C26, C35 electrolytic capacitor 10 µF, 63 V
C24, C25 multilayer ceramic chip capacitor;

C28 multilayer ceramic chip capacitor;

C29 multilayer ceramic chip capacitor;

C33, C34 multilayer ceramic chip capacitor;

L1, L3, L22, L24 stripline; note 2 50 Ω length 80 mm

L2, L23 semi-rigid cable; note3 50 Ω ext. dia. 3.6 mm

L4, L5 stripline; note 2 43 Ω length 24 mm

L6, L7 stripline; note 2 43 Ω length 14.5 mm

L8, L9 stripline; note 2 43 Ω length 4.4 mm

L10, L11 stripline; note 2 43 Ω length 3.2 mm

L12, L13 stripline; note 2 43 Ω length 15 mm

multilayer ceramic chip capacitor 100 nF, 50 V 2222 852 47104

note 1

note 1

multilayer ceramic chip capacitor;

note 1

note 1

note 1

note 1

note 1

27 pF, 500 V

3 × 18 pF
in parallel, 500 V

100 pF, 500 V

2 × 1 nFinparallel,
500 V

3 × 33 pF in
parallel, 500 V

1 nF, 500 V

2 × 470 pF in
parallel, 500 V

2 × 10 pF +
1 × 18 pF in
parallel, 500 V

2 × 5.6 pF in
parallel, 500 V

5.6 pF, 500 V

width 4.8 mm

outer conductor
length 80 mm

width 6 mm

width 6 mm

width 6 mm

width 6 mm

width 6 mm

2003 Sep 19 16

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO.

L14, L17 2 × grade 3B Ferroxcube

wideband HF chokes in parallel
L15, L16 1

L18, L19 stripline; note 2 43 Ω length 13 mm

L20, L21 stripline; note 2 43 Ω length 29.5 mm

R1 metal film resistor 10 Ω, 0.4 W
R2, R7 10 turns potentiometer 50 kΩ
R3, R6 metal film resistor 1 kΩ, 0.4 W
R4, R5 metal film resistor 2 × 5.62 Ω, in

R8, R9 metal film resistor 10 Ω±5%, 1 W
R10 metal film resistor 4 × 42.2 Ω in

R11 metal film resistor 5.11 kΩ, 1W
IC1 voltage regulator 78L05

3

⁄4turns enamelled 2 mm copper

wire

40 nH int. dia. 10 mm

leads 2 × 7mm
space 1 mm

width 6 mm

width 6 mm

parallel, 0.4 W

parallel, 1 W

4312 020 36642

Notes

1. American Technical Ceramics capacitor, type 100B or other capacitor of the same quality.

2. L1, L3 to L13, L18 to L22 and L24 are microstriplines on a double copper-clad printed-circuit board, with fibre-glass
reinforced PTFE dielectric (εr= 2.2), thickness1⁄16inch; thickness of copper sheet 2 × 35 µm.

3. L2 and L23 are soldered on to striplines L1 and L24 respectively.

2003 Sep 19 17

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

handbook, full pagewidth

strap

strap

L1

50 Ω
input

V

Hollow

rivets

DD1

R1

C30

C23

C32

C26

C31

130

C33

L23

C34

R10

L22

L24

Hollow

rivets

strap

strap

MBC436

100

50 Ω
output

119

C15

C18

strap

strap

C24

C14

L14

R8

L14

L15

L18

C28

C21

L19

L16

L17

R9

L17

C25 C27

C19

V

L20
L21

V

C22

DD1

C29

DD2

strap

strap

to R2,R7

C38

slider R2

C3

C4

slider R7

IC1

C35

C5

L4
L5

C10

C13

C36

C6

C37

C11

R6

C12

R3

R4

L7 L9

R5

C16

L8L6

C17

C9

C8

C7

L10

L11

L12

C20

L13

R11

L2

C1

C2

L3

Dimensions in mm.

The circuit and components are situated on one side of the PTFE fibre-glass board, the other side being fully metallized to serve as an earth.
Earth connections are made by means of copper straps for a direct contact between upper and lower sheets.

Fig.22 Printed-circuit board and component layout for 225 MHz class-AB test circuit.

2003 Sep 19 18

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

handbook, halfpage

2

z

i

(Ω)

1

0

−1

–2

150 200 250

Class-AB operation; VDS= 50 V; IDQ=2×0.5 A;

= 2.8 Ω (per section); PL= 250 W.

R

GS

r

i

x

i

f (MHz)

MGE611

Fig.23 Input impedance as a function of frequency

(series components); typical values per
section.

handbook, halfpage

3

X

Z

L

(Ω)

2

1

0

150 250200

Class-AB operation; VDS= 50 V; IDQ=2×0.5 A;

= 2.8 Ω (per section); PL= 250 W.

R

GS

L

R

L

MGE625

f (MHz)

Fig.24 Load impedance as a function of frequency

(series components); typical values per
section.

handbook, halfpage

Fig.25 Definition of MOS impedance.

20

handbook, halfpage

G

p

(dB)

10

Z

i

Z

MBA379

L

0

150 200 250

Class-AB operation; VDS= 50 V; IDQ=2×0.5 A;

= 2.8 Ω (per section); PL= 250 W.

R

GS

f (MHz)

MGE624

Fig.26 Power gain as a function of frequency;

typical values per section.

2003 Sep 19 19

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

BLF278 scattering parameters

VDS= 50 V; ID= 500 mA; note 1

f (MHz)

s

11

s

21

s

12

s

22

|s11| ∠Φ |s21| ∠Φ |s12| ∠Φ |s22| ∠Φ

5 0.87 −142.1 60.05 104.3 0.00 −19.4 0.83 160.9
10 0.88 −159.8 32.09 91.4 0.00 0.68 167.5 165.8
20 0.88 −169.0 15.70 77.3 0.01 13.4 0.62 177.6
30 0.88 −171.2 9.98 68.4 0.01 3.4 0.64 −175.8
40 0.89 −172.2 6.99 61.0 0.01 −4.4 0.66 −171.2
50 0.91 −172.9 5.24 55.0 0.01 −10.3 0.70 −168.1
60 0.92 −173.5 4.08 49.6 0.01 −15.0 0.74 −166.8
70 0.93 −174.1 3.26 44.9 0.01 −18.3 0.78 −166.5
80 0.94 −174.7 2.66 41.0 0.01 −19.8 0.80 −166.5
90 0.95 −175.2 2.22 37.5 0.00 −19.7 0.83 −166.7

100 0.95 −175.7 1.88 34.0 0.00 −18.0 0.85 −167.4
125 0.97 −176.9 1.27 26.8 0.00 −1.9 0.88 −169.4
150 0.97 −177.9 0.91 22.7 0.00 35.3 0.91 −170.0
175 0.98 −178.7 0.69 19.5 0.00 65.3 0.94 −170.8
200 0.98 −179.5 0.54 16.0 0.00 78.0 0.95 −172.4
250 0.99 179.2 0.35 12.1 0.01 86.7 0.96 −174.0
300 0.99 178.1 0.25 9.1 0.01 87.8 0.98 −175.5
350 0.99 177.1 0.19 8.2 0.01 90.3 0.98 −176.5
400 0.99 176.1 0.14 7.2 0.01 91.4 0.99 −177.6
450 0.99 175.1 0.11 8.1 0.02 92.2 0.99 −178.3
500 0.99 174.2 0.09 9.7 0.02 91.5 0.99 −179.2
600 0.99 172.4 0.07 14.8 0.02 91.4 0.99 179.5
700 0.99 170.7 0.05 24.0 0.03 91.6 0.99 178.3
800 0.99 168.9 0.04 35.6 0.03 92.5 1.00 177.1
900 0.99 167.1 0.04 46.0 0.04 93.1 1.00 176.0

1000 0.99 165.2 0.04 60.3 0.04 94.1 1.00 175.0

Note

1. For more extensive s-parameters see internet:
http://www.semiconductors.philips.com/markets/communications/wirelesscommunications/broadcast.

2003 Sep 19 20

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

PACKAGE OUTLINE

Flanged double-ended ceramic package; 2 mounting holes; 4 leads SOT262A1

D

A

F

D

1

U

1

q

H

1

w

M M

2

C

12

U

H

2

5

A

e

DIMENSIONS (millimetre dimensions are derived from the original inch dimensions)

5.85

5.58

c

0.16

0.10

0.006

0.004

Db

22.17

21.46

0.873

0.845

D

21.98

21.71

0.865

0.855

EE

e U

1

10.27

11.05

10.05

0.404

0.435

0.396

UNIT

mm

inches

A

5.77

5.00

0.227

0.197

0.230

0.220

43

b

0 5 10 mm

scale

F

1

10.29

10.03

0.405

0.396

1.78

1.52

0.070

0.060

21.08

19.56

0.830

0.770

H

w

3

M

H

1

17.02

16.51

0.670

0.650

B

C

p

w

1

p

Q

3.28

2.85

3.02

2.59

0.129

0.112

0.119

0.102

c

E

1

M M M

AB

Q

qw

U

1

34.17

27.94

33.90

1.345

1.335

w

2

9.91

9.65

0.390

0.380

E

w

3

2

1

0.250.25 0.51

0.0100.010 0.0201.100

OUTLINE

VERSION

SOT262A1

IEC JEDEC EIAJ

REFERENCES

2003 Sep 19 21

EUROPEAN

PROJECTION

ISSUE DATE

99-03-29

Philips Semiconductors Product Specification

VHF push-pull power MOS transistor BLF278

DATA SHEET STATUS

LEVEL

DATA SHEET

STATUS

(1)

PRODUCT

STATUS

(2)(3)

DEFINITION

I Objective data Development This data sheet contains data from the objective specification for product

development. Philips Semiconductors reserves the right to change the
specification in any manner without notice.

II Preliminary data Qualification This data sheet contains data from the preliminary specification.

Supplementary data will be published at a later date. Philips
Semiconductors reserves the right to change the specification without
notice, in order to improve the design and supply the best possible
product.

III Product data Production This data sheet contains data from the product specification. Philips

Semiconductors reserves the right to make changes at any time in order
to improve the design, manufacturing and supply. Relevant changes will
be communicated via a Customer Product/Process Change Notification
(CPCN).

Notes

1. Please consult the most recently issued data sheet before initiating or completing a design.

2. The product status of the device(s) described in this data sheet may have changed since this data sheet was
published. The latest information is available on the Internet at URL http://www.semiconductors.philips.com.

3. For data sheets describing multiple type numbers, the highest-level product status determines the data sheet status.

DEFINITIONS

DISCLAIMERS

Short-form specification  The data in a short-form

specification is extracted from a full data sheet with the
same type number and title. For detailed information see
the relevant data sheet or data handbook.

Limiting values definition  Limiting values given are in
accordance with the Absolute Maximum Rating System
(IEC 60134). 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
attheseorat 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  Applications that are
described herein for any of these products are for
illustrative purposes only. Philips Semiconductors make
norepresentation or warranty that such applicationswillbe
suitable for the specified use without further testing or
modification.

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
Semiconductorscustomers using or selling theseproducts
for use in such applications do so at their own risk and
agree to fully indemnify Philips Semiconductors for any
damages resulting from such application.

Right to make changes  Philips Semiconductors
reserves the right to make changes in the products ­including circuits, standard cells, and/or software ­described or contained herein in order to improve design
and/or performance. When the product is in full production
(status ‘Production’), relevant changes will be
communicated via a Customer Product/Process Change
Notification (CPCN). Philips Semiconductors assumes no
responsibility or liability for the use of any of these
products, conveys no licence or title under any patent,
copyright, or mask work right to these products, and
makes no representations or warranties that these
products are free from patent, copyright, or mask work
right infringement, unless otherwise specified.

2003 Sep 19 22

Philips Semiconductors – a w orldwide compan y

Contact information

For additional information please visit http://www.semiconductors.philips.com. Fax: [phone]
For sales offices addresses send e-mail to: [e-mail].

© Koninklijke Philips Electronics N.V. 2003
All rights are reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner.

The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed
without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license
under patent- or other industrial or intellectual property rights.

Printed in The Netherlands 613524/04/pp23 Date of release: 2003 Sep 19 Document order number: 9397 750 11599

SCA75