SCHOTTKY RECTIFIER
80 Amp
81CNQ... SERIES
PD-2.237 rev. B 01/99
www.irf.com
1
I
F(AV)
Rectangular
80
A
waveform
V
RRM
range
35 to 45
V
I
FSM
@ tp = 5 s sine
4600
A
V
F
@
40 Apk, T
J
= 125C
0.54
V
(per leg)
T
J
range
- 55 to 175
C
Characteristics
81CNQ...
Units
Major Ratings and Characteristics
Case Styles
D61-8
D61-8-SM
D61-8-SL
81CNQ...
81CNQ...SM
81CNQ...SL
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
Description/Features
81CNQ... Series
2
PD-2.237 rev. B 01/99
www.irf.com
T
J
Max. Junction Temperature Range
-55 to 175
C
T
stg
Max. Storage Temperature Range
-55 to 175
C
R
thJC
Max. Thermal Resistance Junction
0.85
C/W
DC operation
* See Fig. 4
to Case (Per Leg)
R
thJC
Max. Thermal Resistance Junction
0.42
C/W
DC operation
to Case (Per Package)
R
thCS
Typical Thermal Resistance, Case
0.30
C/W
Mounting surface , smooth and greased
to Heatsink (D61-8 Only)
wt
Approximate Weight
7.8 (0.28)
g (oz.)
T
Mounting Torque
Min.
40 (35)
(D61-8 Only)
Max.
58 (50)
Thermal-Mechanical Specifications
Kg-cm
(Ibf-in)
V
FM
Max. Forward Voltage Drop
0.60
V
@ 40A
(Per Leg) * See Fig. 1
(1)
0.74
V
@ 80A
0.54
V
@ 40A
0.66
V
@ 80A
I
RM
Max. Reverse Leakage Current
5
mA
T
J
= 25 C
(Per Leg) * See Fig. 2
(1)
45
mA
T
J
= 125 C
C
T
Max. Junction Capacitance (Per Leg)
2600
pF
V
R
= 5V
DC
, (test signal range 100Khz to 1Mhz) 25C
L
S
Typical Series Inductance (Per Leg)
5.5
nH
Measured lead to lead 5mm from package body
dv/dt Max. Voltage Rate of Change
10,000
V/ s
(Rated V
R
)
T
J
= 25 C
T
J
= 125 C
Electrical Specifications
(1) Pulse Width < 300s, Duty Cycle <2%
V
R
= rated V
R
Absolute Maximum Ratings
Following any rated
load condition and with
rated V
RRM
applied
Parameters
81CNQ Units
Conditions
I
F(AV)
Max. Average Forward Current
80
A
50% duty cycle @ T
C
= 141 C, rectangular wave form
* See Fig. 5
I
FSM
Max. Peak One Cycle Non-Repetitive
4600
5s Sine or 3s Rect. pulse
Surge Current (Per Leg) * See Fig. 7
790
10ms Sine or 6ms Rect. pulse
E
AS
Non-Repetitive Avalanche Energy
54
mJ
T
J
= 25 C, I
AS
= 8 Amps, L = 1.7 mH
(Per Leg)
I
AR
Repetitive Avalanche Current
8
A
Current decaying linearly to zero in 1 sec
(Per Leg)
Frequency limited by T
J
max. V
A
= 1.5 x V
R
typical
A
Part number
81CNQ035
81CNQ040
81CNQ045
V
R
Max. DC Reverse Voltage (V)
V
RWM
Max. Working Peak Reverse Voltage (V)
Voltage Ratings
35
40
45
Parameters
81CNQ Units
Conditions
Parameters
81CNQ Units
Conditions
81CNQ... Series
3
PD-2.237 rev. B 01/99
www.irf.com
Fig. 2 - Typical Values Of Reverse Current
Vs. Reverse Voltage (Per Leg)
Fig. 3 - Typical Junction Capacitance
Vs. Reverse Voltage (Per Leg)
Fig. 4 - Max. Thermal Impedance Z
thJC
Characteristics (Per Leg)
Fig. 1 - Max. Forward Voltage Drop Characteristics
(Per Leg)
0.1
1
10
100
1000
0
0.1 0.2
0.3
0.4
0.5
0.6
0.7 0.8
0.9
1
F
FM
Forward Voltage Drop - V (V)
In
s
t
a
n
t
a
n
e
o
u
s
F
o
r
w
a
r
d
C
u
rre
n
t
-
I
(
A
)
T = 175C
T = 125C
T = 25C
J
J
J
0.001
0.01
0.1
1
10
100
1000
0
5
10
15
20
25
30
35
40
45
R
R
150C
125C
100C
75C
50C
25C
R
e
v
e
rs
e
C
u
rre
n
t
-
I
(
m
A
)
Reverse Voltage - V (V)
T = 175C
J
100
1000
10000
0
10
20
30
40
50
R
T
J
u
n
c
ti
o
n
C
a
p
a
c
i
ta
n
c
e
-
C
(
p
F)
Reverse Voltage - V (V)
T = 25C
J
0.01
0.1
1
0.00001
0.0001
0.001
0.01
0. 1
1
10
100
th
J
C
t , Rectangular Pulse Duration (Seconds)
Single Pulse
(Thermal Resistance)
1
T
h
er
m
a
l
I
m
p
e
d
a
n
c
e
Z
(
C
/
W
)
Notes:
1. Duty factor D = t / t
2. Peak T = P x Z + T
1
2
J
thJ C
C
DM
D = 0.50
D = 0.33
D = 0.25
D = 0.17
D = 0.08
2
t
1
t
P
DM
81CNQ... Series
4
PD-2.237 rev. B 01/99
www.irf.com
Fig. 7 - Max. Non-Repetitive Surge Current (Per Leg)
Fig. 5 - Max. Allowable Case Temperature
Vs. Average Forward Current (Per Leg)
Fig. 8 - Unclamped Inductive Test Circuit
Fig. 6 - Forward Power Loss Characteristics
(Per Leg)
FREE-WHEEL
DIODE
40HFL40S02
CURRENT
MONITOR
HIGH-SPEED
SWITCH
IRFP460
L
DUT
Rg = 25 ohm
Vd = 25 Volt
+
0
4
8
12
16
20
24
28
32
0
10
20
30
40
50
60
DC
A
v
e
r
ag
e
P
o
w
e
r
Lo
ss -
(
W
at
t
s
)
F(AV)
RMS Limit
Average Forward Current - I (A)
D = 0.08
D = 0.17
D = 0.25
D = 0.33
D = 0.50
140
150
160
170
180
0
10
20
30
40
50
60
DC
A
l
l
o
wabl
e
C
a
se
T
e
m
p
e
r
at
ur
e
-
(
C
)
F(AV)
Average Forward Current - I (A)
R (DC) = 0.85 C/W
thJC
100
1000
10000
10
100
1000
10000
FS
M
N
o
n
-
R
e
p
e
t
i
t
i
v
e
S
u
r
g
e
C
u
r
r
e
n
t
-
I
(
A
)
p
At Any Rated Load Condition
And With Rated V Applied
Following Surge
RRM
Square Wave Pulse Duration - t (microsec)
81CNQ... Series
5
PD-2.237 rev. B 01/99
www.irf.com
Outline Table
Outline D61-8-SM
Dimensions are in millimeters and (inches)
Outline D61-8
Dimensions are in millimeters and (inches)
81CNQ... Series
6
PD-2.237 rev. B 01/99
www.irf.com
Outline Table
WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245 U.S.A. Tel: (310) 322 3331. Fax: (310) 322 3332.
EUROPEAN HEADQUARTERS: Hurst Green, Oxted, Surrey RH8 9BB, U.K. Tel: ++ 44 1883 732020. Fax: ++ 44 1883 733408.
IR CANADA: 15 Lincoln Court, Brampton, Markham, Ontario L6T3Z2. Tel: (905) 453 2200. Fax: (905) 475 8801.
IR GERMANY: Saalburgstrasse 157, 61350 Bad Homburg. Tel: ++ 49 6172 96590. Fax: ++ 49 6172 965933.
IR ITALY: Via Liguria 49, 10071 Borgaro, Torino. Tel: ++ 39 11 4510111. Fax: ++ 39 11 4510220.
IR FAR EAST: K&H Bldg., 2F, 30-4 Nishi-Ikebukuro 3-Chome, Toshima-Ku, Tokyo, Japan 171. Tel: 81 3 3983 0086.
IR SOUTHEAST ASIA: 1 Kim Seng Promenade, Great World City West Tower,13-11, Singapore 237994. Tel: ++ 65 838 4630.
IR TAIWAN: 16 Fl. Suite D.207, Sec. 2, Tun Haw South Road, Taipei, 10673, Taiwan. Tel: 886 2 2377 9936.
http://www.irf.com
Fax-On-Demand: +44 1883 733420 Data and specifications subject to change without notice.
Outline D61-8-SL
Dimensions are in millimeters and (inches)
FOOT PRINT
PDF 
ZIP