VISHAY BF998, BF998R, BF998RW User Manual

查询BF998A供应商

BF998/BF998R/BF998RW

N–Channel Dual Gate MOS-Fieldeffect Tetrode,
Depletion Mode

Electrostatic sensitive device.
Observe precautions for handling.

Applications

Input and mixer stages in UHF tuners.

Features

D

Integrated gate protection diodes

D

Low noise figure

D

Low feedback capacitance

D

High cross modulation performance

D

Low input capacitance

D

High AGC-range

D

High gain

Vishay Telefunken

21

94 9279

13 579

43

BF998 Marking: MO
Plastic case (SOT 143)
1 = Source, 2 = Drain, 3 = Gate 2, 4 = Gate 1

2

1

13 56613 654

34

BF998RW Marking: WMO
Plastic case (SOT 343R)
1 = Source, 2 = Drain, 3 = Gate 2, 4 = Gate 1

21

94 9278

95 10831

43

BF998R Marking: MOR
Plastic case (SOT 143R)
1 = Source, 2 = Drain, 3 = Gate 2, 4 = Gate 1

Document Number 85011
Rev. 4, 23-Jun-99

www.vishay.de • FaxBack [phone]

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BF998/BF998R/BF998RW

G2S

Vishay Telefunken

Absolute Maximum Ratings

T

= 25_C, unless otherwise specified

amb

Parameter Test Conditions Symbol Value Unit
Drain - source voltage V
Drain current I
Gate 1/Gate 2 - source peak current ±I
Gate 1/Gate 2 - source voltage ±V
Total power dissipation T

≤ 60 °C P

amb

Channel temperature T
Storage temperature range T

DS

D

G1/G2SM

G1S/G2S

tot
Ch
stg

Maximum Thermal Resistance

T

= 25_C, unless otherwise specified

amb

Parameter Test Conditions Symbol Value Unit

Channel ambient on glass fibre printed board (25 x 20 x 1.5) mm

plated with 35mm Cu

3

R

thChA

12 V
30 mA
10 mA

7 V
200 mW
150

–65 to +150

450 K/W

°

C

°

C

Electrical DC Characteristics

T

= 25_C, unless otherwise specified

amb

Parameter Test Conditions Type Symbol Min Typ Max Unit

Drain - source
breakdown voltage

Gate 1 - source
breakdown voltage

Gate 2 - source
breakdown voltage

Gate 1 - source
leakage current

Gate 2 - source
leakage current

Drain current VDS = 8 V, V

Gate 1 - source
cut-off voltage

Gate 2 - source
cut-off voltage

ID = 10 mA,
–V

= –V

G1S

±I

= 10 mA,

G1S

V

= VDS = 0

G2S

±I

= 10 mA,

G2S

V

= VDS = 0

G1S

±V

= 5 V,

G1S

V

= VDS = 0

G2S

±V

= 5 V,

G2S

V

= VDS = 0

G1S

V

= 4 V

G2S

VDS = 8 V, V
ID = 20 mA

VDS = 8 V, V
ID = 20 mA

G2S

G1S

G2S

G1S

= 4 V

= 0,

= 4 V,

= 0,

BF998/BF998R/

BF998RW

BF998A/BF998RA/

BF998RAW

BF998B/BF998RB/

BF998RBW

V

(BR)DS

±V

(BR)G1SS

±V

(BR)G2SS

±I

±I

I

I

I

–V

G1S(OFF)

–V

G2S(OFF)

G1SS

G2SS

DSS

DSS

DSS

12 V

7 14 V

7 14 V

4 18 mA

4 10.5 mA

9.5 18 mA

1.0 2.0 V

0.6 1.0 V

50 nA

50 nA

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Document Number 85011

Rev. 4, 23-Jun-99

Electrical AC Characteristics

g

g

BF998/BF998R/BF998RW

Vishay Telefunken

VDS = 8 V, ID = 10 mA, V

= 4 V, f = 1 MHz , T

G2S

= 25_C, unless otherwise specified

amb

Parameter Test Conditions Symbol Min Typ Max Unit
Forward transadmittance y
Gate 1 input capacitance C
Gate 2 input capacitance V

G1S

= 0, V

= 4 V C

G2S

Feedback capacitance C
Output capacitance C
Power gain GS = 2 mS, GL = 0.5 mS, f = 200 MHz G

GS = 3,3 mS, GL = 1 mS, f = 800 MHz G

AGC range V

= 4 to –2 V, f = 800 MHz

G2S

 21 24 mS

21s

2.1 2.5 pF

1.1 pF
25 fF

1.05 pF
28 dB

40 dB

D

issg1
issg2

rss

oss

ps
ps

G

ps

16.5 20 dB

Noise figure GS = 2 mS, GL = 0.5 mS, f = 200 MHz F 1.0 dB

GS = 3,3 mS, GL = 1 mS, f = 800 MHz F 1.5 dB

Document Number 85011
Rev. 4, 23-Jun-99

www.vishay.de • FaxBack [phone]

3 (9)