PD-2.237 rev. B 01/99
81CNQ... SERIES
SCHOTTKY RECTIFIER
80 Amp
Major Ratings and Characteristics
Characteristics
I
F(AV)
Rectangular
waveform
V
RRM
range
I
FSM
@ tp = 5 µs sine
V
F
@ 40 Apk, T
J
= 125°C
(per leg)
range
35 to 45
4600
0.54
V
A
V
Description/Features
Units
A
The 81CNQ center tap Schottky rectifier module series has
been optimized for low reverse leakage at high temperature.
The proprietary barrier technology allows for reliable operation
up to 175 °C junction temperature. Typical applications are in
switching power supplies, converters, free-wheeling diodes,
and reverse battery protection.
175 °C T
J
operation
Center tap module
High purity, high temperature epoxy encapsulation for
enhanced mechanical strength and moisture resistance
Low forward voltage drop
High frequency operation
Guard ring for enhanced ruggedness and long term
reliability
Low profile, small footprint, high current package
81CNQ...
80
T
J
- 55 to 175
°C
Case Styles
81CNQ...
81CNQ...SM
81CNQ...SL
D61-8
D61-8-SM
D61-8-SL
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1
81CNQ... Series
PD-2.237 rev. B
01/99
Voltage Ratings
Part number
V
R
Max. DC Reverse Voltage (V)
35
40
45
V
RWM
Max. Working Peak Reverse Voltage (V)
81CNQ035
81CNQ040
81CNQ045
Absolute Maximum Ratings
Parameters
I
F(AV)
Max. Average Forward Current
* See Fig. 5
I
FSM
E
AS
I
AR
Max. Peak One Cycle Non-Repetitive
Surge Current (Per Leg) * See Fig. 7
Non-Repetitive Avalanche Energy
(Per Leg)
Repetitive Avalanche Current
(Per Leg)
4600
790
54
8
A
mJ
A
Following any rated
load condition and with
10ms Sine or 6ms Rect. pulse rated V
RRM
applied
5µs Sine or 3µs Rect. pulse
T
J
= 25 °C, I
AS
= 8 Amps, L = 1.7 mH
Current decaying linearly to zero in 1 µsec
Frequency limited by T
J
max. V
A
= 1.5 x V
R
typical
81CNQ Units
80
A
Conditions
50% duty cycle @ T
C
= 141 °C, rectangular wave form
Electrical Specifications
Parameters
V
FM
Max. Forward Voltage Drop
(Per Leg) * See Fig. 1
(1)
81CNQ Units
0.60
0.74
0.54
0.66
5
45
2600
5.5
10,000
V
V
V
V
mA
mA
pF
nH
V/ µs
@ 40A
@ 80A
@ 40A
@ 80A
Conditions
T
J
= 25 °C
T
J
= 125 °C
V
R
= rated V
R
I
RM
C
T
L
S
Max. Reverse Leakage Current
(Per Leg) * See Fig. 2
(1)
Max. Junction Capacitance (Per Leg)
Typical Series Inductance (Per Leg)
T
J
= 25 °C
T
J
= 125 °C
V
R
= 5V
DC
, (test signal range 100Khz to 1Mhz) 25°C
Measured lead to lead 5mm from package body
dv/dt Max. Voltage Rate of Change
(Rated V
R
)
(1) Pulse Width < 300µs, Duty Cycle <2%
Thermal-Mechanical Specifications
Parameters
T
J
T
stg
Max. Junction Temperature Range
Max. Storage Temperature Range
81CNQ Units
-55 to 175
-55 to 175
0.85
0.42
0.30
7.8 (0.28)
Min.
Max.
40 (35)
58 (50)
°C
°C
Conditions
R
thJC
Max. Thermal Resistance Junction
to Case (Per Leg)
R
thJC
Max. Thermal Resistance Junction
to Case (Per Package)
R
thCS
Typical Thermal Resistance, Case
to Heatsink
(D61-8 Only)
wt
T
Approximate Weight
Mounting Torque
(D61-8 Only)
°C/W DCoperation
°C/W DCoperation
* See Fig. 4
°C/W Mounting surface , smooth and greased
g (oz.)
Kg-cm
(Ibf-in)
2
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81CNQ... Series
PD-2.237 rev. B
01/99
1000
1000
100
10
1
0.1
0.01
0.001
0
5
10
15
20 25 30
35 40
45
Reverse Voltage - V
R
(V)
T
J
= 175°C
150°C
125°C
100°C
75°C
50°C
25°C
100
(A)
Instantaneous Forward Current - I
F
10
T
J
= 175°C
Reverse Current - I
R
(mA)
Fig. 2 - Typical Values Of Reverse Current
Vs. Reverse Voltage (Per Leg)
10000
(pF)
T
T
J
= 125°C
T
J
= 25°C
1
Junction Capacitance - C
T = 25°C
J
1000
0.1
0
0.1 0.2
0.3
0.4
0.5
0.6
0.7 0.8
0.9
1
Forward Voltage Drop - V
FM
(V)
100
0
10
20
30
40
50
Reverse Voltage - V
R
(V)
Fig. 1 - Max. Forward Voltage Drop Characteristics
(PerLeg)
1
Thermal Impedance Z
thJC
(°C/W)
Fig. 3 - Typical Junction Capacitance
Vs. Reverse Voltage (Per Leg)
0.1
D=
D=
D=
D=
D=
0.50
0.33
0.25
0.17
0.08
P
DM
Notes:
Single Pulse
(Thermal Resistance)
0.01
0.00001
t1
t2
1. Duty factor D = t 1/ t 2
2. Peak T
J
= P
DM
x Z
thJ C
+ T
C
0.1
1
10
100
0.0001
0.001
0.01
t 1 , Rectangular Pulse Duration (Seconds)
Fig. 4 - Max. Thermal Impedance Z
thJC
Characteristics (Per Leg)
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81CNQ... Series
PD-2.237 rev. B
01/99
180
Allowable Case Temperature - (°C)
R
thJC
(DC) = 0.85 °C/W
170
Average Power Loss - (Watts)
32
28
24
20
16
12
8
4
RMS Limit
DC
D = 0.08
D = 0.17
D = 0.25
D = 0.33
D = 0.50
160
DC
150
140
0
10
20
30
40
50
60
Average Forward Current - I
F(AV)
(A)
0
0
10
20
30
40
50
60
Average Forward Current - I
F(AV)
(A)
Fig. 5 - Max. Allowable Case Temperature
Vs. Average Forward Current (Per Leg)
(A)
10000
Fig. 6 - Forward Power Loss Characteristics
(PerLeg)
Non-Repetitive Surge Current - I
FSM
1000
At Any Rated Load Condition
And With Rated V
RRM
Applied
Following Surge
100
10
100
1000
10000
Square Wave Pulse Duration - t p (microsec)
Fig. 7 - Max. Non-Repetitive Surge Current (Per Leg)
L
HIGH-SPEED
SWITCH
FREE-WHEEL
DIODE
40HFL40S02
Vd = 25 Volt
DUT
IRFP460
Rg = 25 ohm
+
CURRENT
MONITOR
Fig. 8 - Unclamped Inductive Test Circuit
4
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81CNQ... Series
PD-2.237 rev. B
01/99
Outline Table
Outline D61-8
Dimensions are in millimeters and (inches)
Outline D61-8-SM
Dimensions are in millimeters and (inches)
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