NXP Semiconductors

Product specification

Dual-gate MOS-FETs

BF908; BF908R

FEATURES

• High forward transfer admittance

• Short channel transistor with high forward transfer

admittance to input capacitance ratio

• Low noise gain controlled amplifier up to 1 GHz.

APPLICATIONS

• VHF and UHF applications with 12 V supply voltage,

such as television tuners and professional

communications equipment.

DESCRIPTION

Depletion type field-effect transistor in a plastic

microminiature SOT143 or SOT143R package. The

transistors are protected against excessive input voltage

surges by integrated back-to-back diodes between gates

and source.

PINNING

CAUTION

The device is supplied in an antistatic package. The

gate-source input must be protected against static

discharge during transport or handling.

PIN

SYMBOL

DESCRIPTION

1

s, b

source

2

d

drain

gate 2

gate 1

Fig.1

Simplified outline (SOT143) and

symbol; BF908.

handbook, halfpage

s,b

d

g

1

g

2

43

2

1

Top view

BF908 marking code:

%M1.

MAM039

Fig.2

Simplified outline (SOT143R) and

symbol; BF908R.

handbook, halfpage

s,b

d

g

1

g

2

MAM040

34

1

2

Top view

BF908R marking code:

%M2.

QUICK REFERENCE DATA

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT

drain-source voltage

−−

12

V

drain current

−−

40

mA

total power dissipation

−−

200

mW

operating junction temperature

−−

150

°C

forward transfer admittance

36

43

50

mS

input capacitance at gate 1

2.4

3.1

4

pF

reverse transfer capacitance

f = 1 MHz

20

30

45

pF

F

noise figure

f = 800 MHz

−

1.5

2.5

dB

Rev. 03 - 14 November 2007

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