ST STPS40120C User Manual

Features

■ High junction temperature capability

■ Avalanche rated

■ Low leakage current

■ Good trade-off between leakage current and

forward voltage drop

STPS40120C

Power Schottky rectifier

A1

A2

K

Description

Dual center tap Schottky rectifier suited for high frequency Switch Mode Power Supply.

Packaged in TO-220AB, TO-220AB narrow leads

2

and I

PAK, this device is intended to be used in notebook and LCD adaptors, desktop SMPS, providing in these applications a margin between the remaining voltages applied on the diode and the voltage capability of the diode.

A2

K

A1

TO-220AB

STPS40120CT

K

A1

TO-220AB narrow leads

STPS40120CTN

Table 1. Device summary

I

F(AV)

120 V

V

RRM

T

j(max)

0.57 V

V

F(typ)

K

A1

I2PAK

STPS40120CR

A2

K

2 x 20 A

175 °C

A2

September 2011 Doc ID 11214 Rev 3 1/9

www.st.com

9

Characteristics STPS40120C

d

-

1 Characteristics

Table 2. Absolute ratings (limiting values, per diode)

Symbol Parameter Value Unit

V

RRM

I

F(RMS)

I

F(AV)

I

FSM

P

ARM

T

stg

T

Ptot

--------------

1. condition to avoid runaway for a diode on its own heatsink

dTj

Table 3. Thermal parameters

Repetitive peak reverse voltage 120 V

Forward rms current 30 A

Average forward current

δ = 0.5

= 145 °C

T

c

Per diode Per device

Surge non repetitive forward current tp = 10 ms sinusoidal 200 A

Repetitive peak avalanche power tp = 1 µs, Tj = 25 °C 10500 W

Storage temperature range -65 to + 175 °C

Maximum operating junction temperature

j

1

--------------------------

<

Rth j a–()

(1)

175 °C

20 40

Symbol Parameter Value Unit

R

th(j-c)

th(c)

Junction to case

Per diode To ta l

Coupling Total 0.1 °C/W

1.6

0.85

When the diodes 1 and 2 are used simultaneously: ΔT

(diode 1) = P(diode 1) x R

j

Table 4. Static electrical characteristics (per diode)

(per diode) + P(diode 2) x R

th(j-c)

th(c)

A

°C/W

Symbol Test conditions Min. Typ. Max. Unit

T

= 25 °C

(1)

I

Reverse leakage current

R

j

T

= 125 °C 4 12 mA

j

Tj = 25 °C

T

= 125 °C 0.57 0.61

j

T

= 25 °C

(2)

V

1. Pulse test: tp = 5 ms, δ < 2%

2. Pulse test: tp = 380 µs, δ < 2%

Forward voltage drop

F

j

= 125 °C 0.69 0.73

T

j

T

= 25 °C

j

= 125 °C 0.83 0.88

T

j

To evaluate the maximum conduction losses use the following equation: P = 0.58 x I

2/9 Doc ID 11214 Rev 3

F(AV)

+ 0.0075 I

F2(RMS)

= V

V

R

RRM

= 7.5 A

I

F

I

= 20 A

F

IF = 40 A

25 μA

0.73

0.9 V

1

STPS40120C Characteristics

Figure 1. Average forward power

dissipation versus average forward current (per diode)

P (W)

F(AV)

20

18

16

14

12

10

8

6

4

2

0

0 2 4 6 8 1012141618202224

δ = 0.05

δ = 0.1

δ = 0.2

I (A)

F(AV)

δ = 0.5

δ

=tp/T

Figure 3. Normalized avalanche power

derating versus pulse duration

P(tp)

ARM

P (1 µs)

ARM

1

0.1

0.01

t (µs)

0.001

0.10.01 1

p

10 100 1000

T

δ = 1

Figure 2. Average forward current versus

ambient temperature (

δ = 0.5, per diode)

I (A)

F(AV)

22

20

18

16

14

12

10

8

6

4

tp

2

0

0 25 50 75 100 125 150 175

δ

=tp/T

T

tp

R=R

th(j-a) th(j-c)

R =15°C/W

th(j-a)

T (°C)

amb

Figure 4. Normalized avalanche power

derating versus junction temperature

P(Tj)

ARM

P (25 °C)

ARM

1.2

1

0.8

0.6

0.4

0.2

0

25 50 75 100 125 150

T (°C)

j

Figure 5. Non repetitive surge peak forward

current versus overload duration (maximum values, per diode)

I (A)

M

240

220

200

180

160

140

120

100

80

60

IM

40

20

0

1.E-03 1.E-02 1.E-01 1.E+00

δ=0.5

t

t(s)

T =25°C

c

T =75°C

c

T =125°C

c

Doc ID 11214 Rev 3 3/9

Figure 6. Relative variation of thermal

impedance junction to ambient versus pulse duration

Z/R

th(j-c) th(j-c)

1.0

0.9

0.8

0.7

δ = 0.5

0.6

0.5

0.4

δ = 0.2

0.3

δ = 0.1

0.2

Single pulse

0.1

0.0

1.E-03 1.E-02 1.E-01 1.E+00

t (s)

p

δ

=tp/T

T

tp