ASTEC AS273H5LPT, AS273H5LPB, AS273H5LPA, AS273H5LP13, AS273H1LPA Datasheet

SEMICONDUCTOR

AS273

Over-Temperature Detector

Features

¥Programmable to three different over-temperature thresholds

¥2.5 V temperature compensated bandgap reference trimmed to 1%

¥Open collector output goes low on over-temp condition

¥±3¡C temperature accuracy

¥Reference shunt current serves to program over-temp threshold

¥Available with 5¡C or 10¡C of temperature hysteresis

¥Available in a wide range of overtemp thresholds to fit most temperature monitoring applications

¥Now available in the SOT-223 for improved substrate temperature sensing

Description

The AS273 is a series of programmable over-temperature detectors. Each is internally composed of a precision 2.5 V shunt reference, a proportional-to-absolute temperature thermal sensor, a comparator with controlled hysteresis, and an open collector output that indicates an over-temp condition. The threshold for the over-temp signal can be set to any of three values on a given part by controlling the magnitude of the reference shunt current.

The AS273 has an excellent absolute temperature accuracy of ±3¡C for each of the three over-temp thresholds. The low power dissipation minimizes any temperature sensing errors due to self-heating. There is either 5¡C or 10¡C of temperature hysteresis to prevent bouncing when an over-temp condition is removed.

The packaging options available with the AS273 make it appealing to a wide variety of temperature-sensing applications. The TO-92 package can be mechanically clamped to a heat sink to monitor the temperature of power devices. The 8L-SOIC and SOT-223 surface mount packages allow for temperature sensing in high component density applications.

Pin Configuration Ñ Top view

SOIC (D)

TO-92 (LP)

SOT-223 (G)

OUT	1	8
N/C	2	7
N/C	3	6
N/C	4	5

VREF

DO NOT USE

DO NOT USE

GROUND

	OUT
OUT
GROUND	GROUND
VREF	VREF

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AS273

Over-Temperature Detector

Ordering Information

AS273 D 1 D A

Circuit Type:

Packaging Option:

Over-Temperature Detector

A

= Ammo Pack

Temperature Option:

B

= Bulk

T

= Tube

(Refer to Table A)

13 = Tape and Reel (13" Reel Dia)

Table A – Temperature Options

Package Style:

D

= SOIC

Code

TOT1

TOT2

TOT3

G

= SOT-223

D

40

45

50

LP = TO-92

F

75

80

85

G

90

95

100

Hysteresis Option:

1 = 10°C

H

105

110

115

5 = 5°C

Functional Block Diagram

VREF

1

CURRENT

PROGRAMMING

OUT

3

+

2.5 V

Ð

	4 mV/K	+
		Ð

2

GND

Pin Function Description

Pin Number	Function	Description
1	VREF	2.5 V shunt reference; current into VREF pin also programs
		over-temperature trip point to one of three TOT values
2	GND	Circuit ground and silicon substrate
3	OUT	Open collector output. Output low when die temperature exceeds
		programmed trip point

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Over-Temperature Detector			AS273
Absolute Maximum Ratings
Parameter	Symbol	Rating	Unit
Reference Current	VREF	±10	mA
Output Current	IOUT	±10	mA
Output Voltage	VOUT	18	V
Continuous Power Dissipation at 25¡C
TO-92	PD	775	mW
8-SOIC	PD	750	mW
SOT-223	PD	1000	mW
Junction Temperature	TJ	150	¡C
Storage Temperature	TSTG	Ð65 to 150	¡C
Lead Temp, Soldering 10 Seconds	TL	300	¡C

Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.

Typical Thermal Resistances

Package	θJA	θJC	Typical Derating
SOT-223	115¡C/W	8¡C/W	8.7 mW/¡C
TO-92	160¡C/W	80¡C/W	6.3 mW/¡C
8L SOIC	175¡C/W	45¡C/W	5.7 mW/¡C

ASTEC Semiconductor

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AS273

Over-Temperature Detector

Electrical Characteristics

Electrical Characteristics are guaranteed over the full junction temperature range (0 to 125¡C). Ambient temperature must be derated based upon power dissipation and package thermal characteristics.

Parameter	Symbol	Test Condition	Min.	Typ.	Max.	Unit
Reference
Reference Voltage	VREF	IREF = 2 mA, TJ = 25¡C	2.500	2.525	2.550	V
Load Regulation	VId	0.65 mA ≤ IREF ≤ 5.5 mA		5	10	mV
Average Temperature Coefficient	VREG/ T	0.65 mA ≤ IREF ≤ 5.5 mA		75		ppm/¡C
Output
Saturation Voltage	VOL	IOUT = 4 mA; TJ > TOT		200	400	mV
Breakdown Voltage	BV	IOUT = 100 µA; TJ < TOT	18	30		V
Leakage Current	IOH	VOUT = 18 V; TJ < TOT		1	1000	nA
Over-Temp Sensing
Temperature Accuracy	TOT(1)	0.7 mA ≤ IREF ≤ 1.3 mA	Ð3		+3	¡C
	TOT(2)	1.55 mA ≤ IREF ≤ 2.6 mA	Ð3		+3	¡C
	TOT(3)	3.0 mA ≤ IREF ≤ 5.0 mA	Ð3		+3	¡C
Hysteresis	HOT	Percentage Error in Nominal Hysteresis	Ð30		+30	%

Test Circuit

+5V

RLOAD

2 kΩ

		VREF							OUT
			AS273
IREF			GND

Figure 1. Test Circuit for Output Hysteresis Curve

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