SO
T2
BF545A; BF545B; BF545C
N-channel silicon junction field-effect transistors
Rev. 4 — 15 September 2011
Product data sheet
1. Product profile
1.1 General description
N-channel symmetrical silicon junction field-effect transistors in a SOT23 package.
CAUTION
This device is sensitive to ElectroStatic Discharge (ESD). Therefore care should be taken
during transport and handling.
3
1.2 Features and benefits
Low leakage level (typ. 500 fA)
High gain
Low cut-off voltage (max. 2.2 V for BF545A).
1.3 Applications
Impedance converters in e.g. electret microphones and infra-red detectors
VHF amplifiers in oscillators and mixers.
1.4 Quick reference data
Table 1.
V
DS
V
GSoff
I
DSS
Quick reference data
Conditions
I
D
= 1
A;
V
DS
= 15 V
V
GS
= 0 V; V
DS
= 15 V
BF545A
BF545B
BF545C
P
tot
y
fs
total power dissipation
forward transfer
admittance
T
amb
25
C
V
GS
= 0 V; V
DS
= 15 V
2
6
12
-
3
-
-
-
-
-
6.5
15
25
250
6.5
mA
mA
mA
mW
mS
Min
-
0.4
Typ
-
-
Max
30
7.8
Unit
V
V
drain-source voltage
gate-source cut-off
voltage
drain current
Symbol Parameter
NXP Semiconductors
BF545A; BF545B; BF545C
N-channel silicon junction field-effect transistors)
2. Pinning information
Table 2.
Pin
1
2
3
Pinning
Description
source (s)
drain (d)
gate (g)
1
2
3
g
d
s
sym054
Simplified outline
Symbol
3. Ordering information
Table 3.
Ordering information
Package
Name
BF545A
BF545B
BF545C
-
Description
plastic surface mounted package; 3 leads
Version
SOT23
Type number
4. Marking
Table 4.
BF545A
BF545B
BF545C
[1]
* = p: made in Hong Kong.
* = t: made in Malaysia.
* = W: made in China.
Marking
Marking code
[1]
20*
21*
22*
Type number
BF545A_BF545B_BF545C
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2011. All rights reserved.
Product data sheet
Rev. 4 — 15 September 2011
2 of 16
NXP Semiconductors
BF545A; BF545B; BF545C
N-channel silicon junction field-effect transistors)
5. Limiting values
Table 5.
Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
V
DS
V
GSO
V
GDO
I
G
P
tot
T
stg
T
j
[1]
Parameter
drain-source voltage (DC)
gate-source voltage
gate-drain voltage (DC)
forward gate current (DC)
total power dissipation
storage temperature
junction temperature
Conditions
open drain
open source
T
amb
25
C
[1]
Min
-
-
-
-
-
65
-
Max
30
30
30
10
250
+150
150
Unit
V
V
V
mA
mW
C
C
Device mounted on an FR4 printed-circuit board, maximum lead length 4 mm; mounting pad for the drain
lead 10 mm
2
.
400
P
tot
(mW)
300
mbb688
200
100
0
0
50
100
150
200
T
amb
(°C)
Fig 1.
Power derating curve.
6. Thermal characteristics
Table 6.
Symbol
R
th(j-a)
[1]
Thermal characteristics
Parameter
thermal resistance from junction to
ambient
Conditions
[1]
Typ
500
Unit
K/W
Device mounted on an FR4 printed-circuit board, maximum lead length 4 mm; mounting pad for the drain
lead 10 mm
2
.
BF545A_BF545B_BF545C
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2011. All rights reserved.
Product data sheet
Rev. 4 — 15 September 2011
3 of 16
NXP Semiconductors
BF545A; BF545B; BF545C
N-channel silicon junction field-effect transistors)
7. Static characteristics
Table 7.
Static characteristics
T
j
= 25
C unless otherwise specified.
Symbol
V
(BR)GSS
V
GSoff
Parameter
gate-source breakdown voltage
gate-source cut-off voltage
Conditions
I
G
=
1 A;
V
DS
= 0 V
I
D
= 200
A;
V
DS
= 15 V
BF545A
BF545B
BF545C
I
D
= 1
A;
V
DS
= 15 V
I
DSS
drain current
V
GS
= 0 V; V
DS
= 15 V
BF545A
BF545B
BF545C
I
GSS
gate-source leakage current
V
GS
=
20
V; V
DS
= 0 V
V
GS
=
20
V; V
DS
= 0 V;
T
j
= 125
C
y
fs
y
os
forward transfer admittance
common source output
admittance
V
GS
= 0 V; V
DS
= 15 V
V
GS
= 0 V; V
DS
= 15 V
2
6
12
-
-
3
-
-
-
-
0.5
-
-
40
6.5
15
25
1000
100
6.5
-
mA
mA
mA
pA
nA
mS
S
0.4
1.6
3.2
0.4
-
-
-
-
2.2
3.8
7.8
7.5
V
V
V
V
Min
30
Typ
-
Max
-
Unit
V
BF545A_BF545B_BF545C
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2011. All rights reserved.
Product data sheet
Rev. 4 — 15 September 2011
4 of 16
NXP Semiconductors
BF545A; BF545B; BF545C
N-channel silicon junction field-effect transistors)
8. Dynamic characteristics
Table 8.
Dynamic characteristics
T
amb
= 25
C unless otherwise specified.
Symbol
C
iss
Parameter
input capacitance
Conditions
V
DS
= 15 V; f = 1 MHz
V
GS
=
10
V
V
GS
= 0 V
C
rss
reverse transfer capacitance
V
DS
= 15 V; f = 1 MHz
V
GS
=
10
V
V
GS
= 0 V
g
is
common source input
conductance
V
DS
= 10 V; I
D
= 1 mA
f = 100 MHz
f = 450 MHz
g
fs
common source transfer
conductance
V
DS
= 10 V; I
D
= 1 mA
f = 100 MHz
f = 450 MHz
g
rs
common source reverse
conductance
V
DS
= 10 V; I
D
= 1 mA
f = 100 MHz
f = 450 MHz
g
os
common source output
conductance
V
DS
= 10 V; I
D
= 1 mA
f = 100 MHz
f = 450 MHz
-
-
30
60
-
-
S
S
-
-
6
40
-
-
S
S
-
-
2
1.8
-
-
mS
mS
-
-
15
300
-
-
S
S
-
-
0.8
0.9
-
-
pF
pF
-
-
1.7
3
-
-
pF
pF
Min
Typ
Max
Unit
30
I
DSS
(mA)
20
mbb467
6
Y
fs
(mS)
5.5
mbb466
5
10
4.5
0
0
−2
−4
−6
V
GSoff
(V)
−8
4
0
−2
−4
−6
V
GSoff
(V)
−8
V
DS
= 15 V; T
j
= 25
C.
V
DS
= 15 V; V
GS
= 0 V; T
j
= 25
C.
Fig 2.
Drain current as a function of gate-source
cut-off voltage; typical values.
Fig 3.
Forward transfer admittance as a function of
gate-source cut-off voltage; typical values.
BF545A_BF545B_BF545C
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2011. All rights reserved.
Product data sheet
Rev. 4 — 15 September 2011
5 of 16