JFET - VHF/UHF Amplifier
Transistor
NChannel
MAXIMUM RATINGS
Rating
Symbol
Value
Unit
DrainSource Voltage
VDS
25
Vdc
GateSource Voltage
VGS
25
Vdc
Gate Current
IG
10
mAdc
THERMAL CHARACTERISTICS
Characteristic
Symbol
Max
Unit
Total Device Dissipation FR5 Board(1)
TA = 25
C
Derate above 25
C
PD
225
1.8
mW
mW/
C
Thermal Resistance, Junction to Ambient
R
q
JA
556
C/W
Junction and Storage Temperature
TJ, Tstg
55 to +150
C
DEVICE MARKING
MMBFJ309LT1 = 6U; MMBFJ310LT1 = 6T
ELECTRICAL CHARACTERISTICS
(TA = 25
C unless otherwise noted)
Characteristic
Symbol
Min
Typ
Max
Unit
OFF CHARACTERISTICS
GateSource Breakdown Voltage (IG = 1.0
Adc, VDS = 0)
V(BR)GSS
25
Vdc
Gate Reverse Current (VGS = 15 Vdc)
Gate Reverse Current
(VGS = 15 Vdc, TA = 125
C)
IGSS
1.0
1.0
nAdc
Adc
Gate Source Cutoff Voltage
MMBFJ309
(VDS = 10 Vdc, ID = 1.0 nAdc)
MMBFJ310
VGS(off)
1.0
2.0
4.0
6.5
Vdc
ON CHARACTERISTICS
ZeroGateVoltage Drain Current
MMBFJ309
(VDS = 10 Vdc, VGS = 0)
MMBFJ310
IDSS
12
24
30
60
mAdc
GateSource Forward Voltage (IG = 1.0 mAdc, VDS = 0)
VGS(f)
1.0
Vdc
SMALLSIGNAL CHARACTERISTICS
Forward Transfer Admittance (VDS = 10 Vdc, ID = 10 mAdc, f = 1.0 kHz)
|Yfs|
8.0
18
mmhos
Output Admittance (VDS = 10 Vdc, ID = 10 mAdc, f = 1.0 kHz)
|yos|
250
mhos
Input Capacitance (VGS = 10 Vdc, VDS = 0 Vdc, f = 1.0 MHz)
Ciss
5.0
pF
Reverse Transfer Capacitance (VGS = 10 Vdc, VDS = 0 Vdc, f = 1.0 MHz)
Crss
2.5
pF
Equivalent ShortCircuit Input Noise Voltage
(VDS = 10 Vdc, ID = 10 mAdc, f = 100 Hz)
en
10
nV
Hz
1. FR5 = 1.0
0.75
0.062 in.
ON Semiconductort
Semiconductor Components Industries, LLC, 2001
November, 2001 Rev. 2
1
Publication Order Number:
MMBFJ309LT1/D
MMBFJ309LT1
MMBFJ310LT1
1
2
3
CASE 31808, STYLE 10
SOT23 (TO236AB)
2 SOURCE
3
GATE
1 DRAIN
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2
70
60
50
40
30
20
, SA
TURA
TION DRAIN CURRENT
(mA)
-5.0
-4.0
-3.0
-2.0
-1.0
0
ID - VGS, GATE-SOURCE VOLTAGE (VOLTS)
I DSS
10
0
70
60
50
40
30
20
10
, DRAIN CURRENT
(mA)
I D
IDSS - VGS, GATE-SOURCE CUTOFF VOLTAGE (VOLTS)
Figure 1. Drain Current and Transfer
Characteristics versus GateSource Voltage
VDS = 10 V
IDSS
+25
C
TA = -55
C
+25
C
+25
C
-55
C
+150
C
+150
C
ID, DRAIN CURRENT (mA)
100 k
10 k
1.0 k
100
1.0 k
100
10
1.0
0.01
0.1 0.2 0.3 0.5 1.0 2.0 3.0 5.0 10 20 30 50 100
, FOR
W
ARD
TRANSCONDUCT
ANCE ( mhos)
Y fs
, OUTPUT
ADMITT
ANCE ( mhos)
Y os
VGS(off) = -2.3 V =
VGS(off) = -5.7 V =
Figure 2. CommonSource Output
Admittance and Forward Transconductance
versus Drain Current
Yfs
Yfs
Yos
VGS, GATE SOURCE VOLTAGE (VOLTS)
5.0
4.0 3.0
2.0
1.0
0
6.0
7.0
8.0
9.0
10
CAP
ACIT
ANCE (pF)
10
7.0
4.0
1.0
0
120
96
72
48
24
0
, ON RESIST
ANCE (OHMS)
R
DS
RDS
Cgs
Cgd
Figure 3. On Resistance and Junction
Capacitance versus GateSource Voltage
MMBFJ309LT1 MMBFJ310LT1
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3
|Y
11
|, |Y
21
|, |Y
22
| (mmhos)
Y 12
(mmhos)
30
24
18
12
6.0
0
1000
100
200
300
500 700
f, FREQUENCY (MHz)
3.0
2.4
1.8
1.2
0.6
|S21|, |S11|
0.45
0.39
0.33
0.27
0.21
0.15
0.85
0.79
0.73
0.67
0.61
0.55
|S12|, |S22|
0.060
0.048
0.036
0.024
0.012
1.00
0.98
0.96
0.94
0.92
0.90
1000
100
200
300
500 700
f, FREQUENCY (MHz)
Figure 4. CommonGate Y Parameter
Magnitude versus Frequency
Figure 5. CommonGate S Parameter
Magnitude versus Frequency
VDS = 10 V
ID = 10 mA
TA = 25
C
Y11
Y21
Y22
Y12
S22
S21
S11
S12
VDS = 10 V
ID = 10 mA
TA = 25
C
f, FREQUENCY (MHz)
21,
11
50
40
30
20
10
0
180
170
160
150
140
130
12,
22
-2
0
-40
-80
-120
-160
-200
-20
-60
-100
-140
-180
87
86
85
84
83
82
1000
100
200
300
500
700
Figure 6. CommonGate Y Parameter
PhaseAngle versus Frequency
f, FREQUENCY (MHz)
11,
12
120
100
80
60
40
20
-20
-40
-60
-80
-100
-120
21,
22
0
-40
-80
-20
-60
-100
1000
100
200
300
500
700
Figure 7. S Parameter PhaseAngle
versus Frequency
22
21
12
11
VDS = 10 V
ID = 10 mA
TA = 25
C
11
21
22
21
11
12
VDS = 10 V
ID = 10 mA
TA = 25
C
MMBFJ309LT1 MMBFJ310LT1
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4
The values for the equation are found in the maximum
ratings table on the data sheet. Substituting these values
into the equation for an ambient temperature TA of 25
C,
one can calculate the power dissipation of the device which
in this case is 225 milliwatts.
INFORMATION FOR USING THE SOT23 SURFACE MOUNT PACKAGE
MINIMUM RECOMMENDED FOOTPRINT FOR SURFACE MOUNTED APPLICATIONS
Surface mount board layout is a critical portion of the
total design. The footprint for the semiconductor packages
must be the correct size to insure proper solder connection
interface between the board and the package. With the
correct pad geometry, the packages will self align when
subjected to a solder reflow process.
SOT23
mm
inches
0.037
0.95
0.037
0.95
0.079
2.0
0.035
0.9
0.031
0.8
SOT23 POWER DISSIPATION
PD =
TJ(max) TA
R
JA
PD =
150
C 25
C
556
C/W
= 225 milliwatts
The power dissipation of the SOT23 is a function of the
pad size. This can vary from the minimum pad size for
soldering to a pad size given for maximum power dissipa-
tion. Power dissipation for a surface mount device is deter-
mined by TJ(max), the maximum rated junction temperature
of the die, R
JA, the thermal resistance from the device
junction to ambient, and the operating temperature, TA.
Using the values provided on the data sheet for the SOT23
package, PD can be calculated as follows:
The 556
C/W for the SOT23 package assumes the use
of the recommended footprint on a glass epoxy printed
circuit board to achieve a power dissipation of 225 milli-
watts. There are other alternatives to achieving higher
power dissipation from the SOT23 package. Another
alternative would be to use a ceramic substrate or an
aluminum core board such as Thermal Clad
TM
. Using a
board material such as Thermal Clad, an aluminum core
board, the power dissipation can be doubled using the same
footprint.
SOLDERING PRECAUTIONS
The melting temperature of solder is higher than the
rated temperature of the device. When the entire device is
heated to a high temperature, failure to complete soldering
within a short time could result in device failure. There-
fore, the following items should always be observed in
order to minimize the thermal stress to which the devices
are subjected.
Always preheat the device.
The delta temperature between the preheat and
soldering should be 100
C or less.*
When preheating and soldering, the temperature of the
leads and the case must not exceed the maximum
temperature ratings as shown on the data sheet. When
using infrared heating with the reflow soldering
method, the difference shall be a maximum of 10
C.
The soldering temperature and time shall not exceed
260
C for more than 10 seconds.
When shifting from preheating to soldering, the
maximum temperature gradient shall be 5
C or less.
After soldering has been completed, the device should
be allowed to cool naturally for at least three minutes.
Gradual cooling should be used as the use of forced
cooling will increase the temperature gradient and
result in latent failure due to mechanical stress.
Mechanical stress or shock should not be applied
during cooling.
* Soldering a device without preheating can cause exces-
sive thermal shock and stress which can result in damage
to the device.
MMBFJ309LT1 MMBFJ310LT1
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5
PACKAGE DIMENSIONS
CASE 31808
ISSUE AF
SOT23 (TO236AB)
D
J
K
L
A
C
B S
H
G
V
3
1
2
DIM
A
MIN
MAX
MIN
MAX
MILLIMETERS
0.1102 0.1197
2.80
3.04
INCHES
B 0.0472 0.0551
1.20
1.40
C 0.0350 0.0440
0.89
1.11
D 0.0150 0.0200
0.37
0.50
G 0.0701 0.0807
1.78
2.04
H 0.0005 0.0040
0.013
0.100
J 0.0034 0.0070
0.085
0.177
K 0.0140 0.0285
0.35
0.69
L 0.0350 0.0401
0.89
1.02
S 0.0830 0.1039
2.10
2.64
V 0.0177 0.0236
0.45
0.60
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: INCH.
3. MAXIMUM LEAD THICKNESS INCLUDES LEAD
FINISH THICKNESS. MINIMUM LEAD THICKNESS
IS THE MINIMUM THICKNESS OF BASE
MATERIAL.
STYLE 10:
PIN 1. DRAIN
2. SOURCE
3. GATE
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