ST STPS1545C User Manual

STPS1545C

Power Schottky rectifier

Features

■very small conduction losses

■negligible switching losses

■extremely fast switching

■avalanche capability specified

Description

Dual center tap Schottky rectifier suited for switch mode power supply and high frequency DC to DC converters.

Packaged either in TO-220AB, D2PAK, I2PAK, or DPAK, this device is especially intended for use in low voltage, high frequency inverters, free wheeling and polarity protection applications.

A1
	K
A2
	A2
K	A2
	A1
A1
TO-220AB	DPAK
STPS1545CT	STPS1545CB
K
A2	A2
A1	K
	A1
D2PAK	I2PAK
STPS1545CG	STPS1545CR

Table 1.	Device summary
	IF(AV)		2 x 7.5 A
	VRRM		45 V
	Tj (max)		175 °C
	VF(max)		0.57 V

November 2010

Doc ID 3503 Rev 7

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Characteristics	STPS1545C

1 Characteristics

Table 2.			Absolute ratings (limiting values)
Symbol			Parameter			Value	Unit
	VRRM		Repetitive peak reverse voltage			45	V
IF(RMS)			Forward rms current			20	A
	IF(AV)		Average forward current δ = 0.5	Tc = 157 °C	Per diode	7.5	A
	IFSM		Surge non repetitive forward current	tp = 10 ms sinusoidal		150	A
	IRRM		Peak repetitive reverse current	tp = 2 µs square		1	A
				F = 1 kHz
	IRSM		Non repetitive peak reverse current	tp = 100 µs square		2	A
	PARM		Repetitive peak avalanche power	tp = 1 µs Tj = 25 °C		2700	W
	Tstg		Storage temperature range			-65 to + 175	°C
	T		Maximum operating junction temperature (1)			175	°C
	j
	dV/dt		Critical rate of rise of reverse voltage			10000	V/µs
1.	dPtot		1
	dTj	< Rth(j – a) condition to avoid thermal runaway for a diode on its own heatsink
	---------------		-------------------------

Table 3.

Thermal resistances

Symbol

Parameter

Value

Unit

Rth(j-c)

Junction to case

Per diode

3.0

°C/W

Total

1.7

Rth(c)

Coupling

0.35

When the diodes 1 and 2 are used simultaneously:

Tj(diode 1) = P(diode1) x Rth(j-c)(Per diode) + P(diode2) x Rth(c)

Table 4.

Static electrical characteristics (per diode)

Symbol

Parameter

Test conditions

Min.

Typ.

Max.

Unit

I (1)

Reverse leakage current

Tj = 25 °C

V

=V

-

-

100

µA

R

RRM

R

Tj = 125 °C

-

5

15

mA

Tj = 125°C

IF = 7.5A

-

0.5

0.57

VF(1)

Forward voltage drop

Tj = 25°C

IF = 15 A

-

-

0.84

V

Tj = 125 °C

IF = 15 A

-

0.65

0.72

1. Pulse test: tp = 380 µs, δ < 2%

To evaluate the conduction losses use the following equation:

P = 0.42 x IF(AV) + 0.020 IF2(RMS)

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STPS1545C	Characteristics
Figure 1. Average forward power dissipation Figure 2.	Average forward current versus
versus average forward current (per	ambient temperature (δ = 0.5, per
diode)	diode)

PF(AV)(W)											9	IF(AV)(A)
6
				δ = 0.1	δ = 0.2
							δ = 0.5				8					Rth(j-a)=Rth(j-c)
5		δ = 0.05									7
4											6		Rth(j-a)=40°C/W
															Rth(j-a)=15°C/W
								δ = 1
											5
3
											4
2									T		3
													T
											2
1
					IF(AV)(A)			δ=tp/T		tp	1	δ=tp/T	tp	Tamb(°C)
0											0
0	1	2	3	4	5	6	7	8	9	10	0	25	50	75	100	125	150	175

Figure 3. Normalized avalanche power	Figure 4. Normalized avalanche power
derating versus pulse duration	derating versus junction
	temperature

PARM(tp)							PARM(Tj)
PARM(1 µs)						PARM(25 °C)
1
						1.2
						1
0.1						0.8
						0.6
0.01						0.4
						0.2
			tp(µs)						Tj(°C)
0.001						0
0.01	0.1	1	10	100	1000	25	50	75	100	125	150

Figure 5. Non repetitive surge peak forward Figure 6.	Relative variation of thermal
current versus overload duration	impedance junction to case versus
(maximum values, per diode)	pulse duration

IM(A)				Zth(j-c)/Rth(j-c)
120				1.0
100				0.8
80
				0.6
60			TC=50°C		δ = 0.5
			TC=100°C	0.4
40
IM			TC=150°C	0.2	δ = 0.2			T
20					δ = 0.1
	t	t(s)				tp(s)
0	δ=0.5			0.0	Single pulse		δ=tp/T	tp
1E-3	1E-2	1E-1	1E+0	1E-4	1E-3	1E-2	1E-1	1E+0

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