Dimensions in millimeters and inches
Outline C - 16
CASE STYLE AND DIMENSIONS
IF(AV) Rectangular 3.3 A
waveform
VRRM 30/40 V
IFSM @ tp = 5 µs sine 450 A
VF@ 3 Apk, TJ = 25°C 0.57 V
TJ- 40 to 150 °C
Characteristics Values Units The 31DQ.. axial leaded Schottky rectifier has been opti-
mized for very low forward voltage drop, with moderate
leakage. Typical applications are in switching power sup-
plies, converters, free-wheeling diodes, and reverse
battery protection.
Low profile, axial leaded outline
High purity, high temperature epoxy encapsulation for
enhanced mechanical strength and moisture resistance
Very low forward voltage drop
High frequency operation
Guard ring for enhanced ruggedness and long term
reliability
Lead-Free plating
Description/Features
Major Ratings and Characteristics
SCHOTTKY RECTIFIER 3.3 Amp
31DQ03
31DQ04
Bulletin PD-2.304 rev. G 04/05
1
www.irf.com
31DQ03, 31DQ04
Bulletin PD-2.304 rev. G 04/05
2www.irf.com
Part number 31DQ03 31DQ04
VRMax. DC Reverse Voltage (V)
VRWM Max. Working Peak Reverse Voltage (V)
Voltage Ratings
30 40
VFM Max. Forward Voltage Drop 0.57 V @ 3A
* See Fig. 1 (1) 0.71 V @ 6A
0.51 V @ 3A
0.62 V @ 6A
IRM Max. Reverse Leakage Current 1 mA TJ = 25 °C
* See Fig. 2 (1) 20 mA TJ = 125 °C
CTTypical Junction Capacitance 190 pF VR = 5VDC (test signal range 100Khz to 1Mhz) 25°C
LSTypical Series Inductance 9.0 nH Measured lead to lead 5mm from package body
dv/dt Max. Voltage Rate of Change 10000 V/µs (Rated VR)
TJ = 25 °C
TJ = 125 °C
VR = rated VR
Parameters 31DQ.. Units Conditions
Electrical Specifications
(1) Pulse Width < 300µs, Duty Cycle <2%
TJMax. Junction Temperature Range (*) -40 to 150 °C
Tstg Max. Storage Temperature Range -40 to 150 °C
RthJA Max. Thermal Resistance Junction 80 °C/W DC operation
to Ambient Without cooling fins
RthJL Typical Thermal Resistance Junction 15 °C/W With fin 20 x 20 (0.79 x 0.79) 1.0 (0.04) thick.
to Lead Dimensions in millimeters (inches)
wt Approximate Weight 1.2 (0.042) g (oz.)
Case Style C - 16
Thermal-Mechanical Specifications
Parameters 31DQ.. Units Conditions
IF(AV) Max. Average Forward Current 3.3 A 50% duty cycle @ TL = 117°C, rectangular wave form
* See Fig. 4
IFSM Max. Peak One Cycle Non-Repetitive 450 5µs Sine or 3µs Rect. pulse
Surge Current * See Fig. 6 90 10ms Sine or 6ms Rect. pulse
EAS Non-Repetitive Avalanche Energy 6.0 mJ TJ = 25 °C, IAS
= 1.0 Amps, L = 12 mH
IAR Repetitive Avalanche Current 1.0 A Current decaying linearly to zero in 1 µsec
Frequency limited by TJ max. VA = 1.5 x VR typical
Absolute Maximum Ratings
Following any rated
load condition and with
rated VRRM applied
A
Parameters 31DQ.. Units Conditions
< thermal runaway condition for a diode on its own heatsink
(*) dPtot 1
dTj Rth( j-a)
31DQ03, 31DQ04
Bulletin PD-2.304 rev. G 04/05
3www.irf.com
Fig. 1 - Max. Forward Voltage Drop Characteristics
Forward Voltage Drop - VFM (V)
Instantaneous Forward Current - IF (A)
Reverse Voltage - VR (V)
Reverse Voltage - VR (V)
Junction Capacitance - CT (pF)
Fig. 3 - Typical Junction Capacitance
Vs. Reverse Voltage
Fig. 2 - Typical Values Of Reverse Current
Vs. Reverse Voltage
Reverse Current - IR (mA)
0.1
1
10
100
0 0.3 0.6 0.9 1.2
T = 150˚C
T = 125˚C
T = 25˚C
J
J
J
0.001
0.01
0.1
1
10
100
0 10203040
25˚C
T = 150˚C
J
125˚C
10
100
1000
0 40 80 120 160 200
T = 25˚C
J
31DQ03, 31DQ04
Bulletin PD-2.304 rev. G 04/05
4www.irf.com
Average Forward Current - IF(AV) (A)
Square Wave Pulse Duration - tp (microsec)
Fig. 6 - Max. Non-Repetitive Surge Current
Allowable Lead Temperature (°C)
Non-Repetitive Surge Current - IFSM
(A)
Fig. 5- Forward Power Loss
Characteristics
Average Forward Current - IF(AV) (A)
Average Power Loss (Watts)
(2) Formula used: TC = TJ - (Pd + PdREV) x RthJC
;
Pd = Forward Power Loss = IF(AV) x VFM @ (IF(AV) / D) (see Fig. 6);
PdREV = Inverse Power Loss = VR1 x IR (1 - D); IR @ VR1
= 80% rated VR
Fig. 4 - Max. Allowable Lead Temperature
Vs. Average Forward Current
0
0.5
1
1.5
2
2.5
012345
DC
RMS Limit
D = 0.20
D = 0.25
D = 0.33
D = 0.50
D = 0.75
10
100
1000
10 100 1000 10000
At Any Rated Load Condition
And With Rated V Applied
Following Surge RRM
70
90
110
130
150
012345
DC
see note (2)
Square wave (D = 0.50)
80% Rated Vr applied
31DQ03, 31DQ04
Bulletin PD-2.304 rev. G 04/05
5www.irf.com
IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105
TAC Fax: (310) 252-7309
Visit us at www.irf.com for sales contact information. 04/05
Data and specifications subject to change without notice.
This product has been designed and qualified for Industrial Level and Lead-Free.
Qualification Standards can be found on IR's Web site.
Ordering Information Table
Device Code
15
24
3
1- 31 = 3.1A (Axial and small packages - Current is x10)
2- D = DO-201 package
3- Q = Schottky Q.. Series
4- 10 = Voltage Ratings
5-y TR = Tape & Reel package (1200 pcs)
y none = Box package (500 pcs)
31 D Q 04 TR
04 = 40V
03 = 30V
