Analog Devices ADM812TART-REEL-7, ADM812TART-REEL, ADM812SART-REEL-7, ADM812SART-REEL, ADM812RART-REEL-7 Datasheet

a Microprocessors

Supervisory Circuit in 4-Lead SOT-143

ADM811/ADM812

FEATURES

Superior Upgrade for MAX811/MAX812 Specified Over Temperature

Low Power Consumption (5 mA Typ)

Precision Voltage Monitor: +3 V, +3.3 V, +5 V Options Reset Assertion Down to 1 V VCC

140 ms Min Power-On Reset

Logic Low RESET Output (ADM811)

Logic High RESET Output (ADM812) Built-In Manual Reset

APPLICATIONS

Microprocessor Systems

Controllers

Intelligent Instruments

Automotive Systems

Safety Systems

Portable Instruments

FUNCTIONAL BLOCK DIAGRAM

	ADM811/ADM812
VCC	RESET	RESET/RESET
	GENERATOR
	VREF
MR	DEBOUNCE	GND

GENERAL DESCRIPTION

The ADM811/ADM812 are reliable voltage monitoring devices suitable for use in most voltage monitoring applications.

The ADM811/ADM812 are designed to monitor five different voltages, each allowing for a 5% or 10% degradation of standard PSU voltages before a reset occurs. These voltages have been selected for the effective monitoring of +3 V, +3.3 V and +5 V supply voltage levels.

Included in this circuit is a debounced Manual Reset input. Reset can be activated using an electrical switch (or an input from another digital device) or by a degradation of the supply voltage. The Manual Reset function is very useful especially if the circuit in which the ADM811/ADM812 is operating enters into a state that can only be detected by the user. Allowing the user to manually reset a system can reduce the damage or danger that could be otherwise caused by an out-of-control or locked up system.

VCC

VCC

ADM811

mP

SYSTEM

MR

RESET

RESET

100kV

GND

GND

Figure 1. Typical Operating Circuit

REV. 0

Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: [phone]	World Wide Web Site: http://www.analog.com
Fax: [phone]	© Analog Devices, Inc., 1999

ADM811/ADM812–SPECIFICATIONS				(VCC = Full Operating Range, TA = TMIN to TMAX, VCC typ = +5 V
				for L/M, +3.3 V for T/S, +3 V for R Models unless otherwise noted)
Parameter	Min	Typ	Max		Units	Test Conditions/Comments
SUPPLY						TA = 0°C to +70°C
Voltage	1.0		5.5		V
	1.2				V	TA = –40°C to +85°C
Current		8	15		µA	VCC < +5.5 V, ADM81_L/M, IOUT = 0 A
		5	10		µA	VCC < +3.6 V, ADM81_R/S/T, IOUT = 0 A
RESET VOLTAGE THRESHOLD						TA = +25°C
ADM81_L	4.54	4.63	4.72		V
ADM81_L	4.50		4.75		V	TA = –40°C to +85°C
ADM81_M	4.30	4.38	4.46		V	TA = +25°C
ADM81_M	4.25		4.50		V	TA = –40°C to +85°C
ADM81_T	3.03	3.08	3.14		V	TA = +25°C
ADM81_T	3.00		3.15		V	TA = –40°C to +85°C
ADM81_S	2.88	2.93	2.98		V	TA = +25°C
ADM81_S	2.85		3.00		V	TA = –40°C to +85°C
ADM81_R	2.58	2.63	2.68		V	TA = +25°C
ADM81_R	2.55		2.70		V	TA = –40°C to +85°C
RESET THRESHOLD					ppm/°C
TEMPERATURE COEFFICIENT		30
VCC TO RESET/RESET DELAY		40			µs	VOD = 125 mV, ADM81_L/M
		20			µs	VOD = 125 mV, ADM81_R/S/T
RESET ACTIVE TIMEOUT PERIOD	140		560		ms	VCC = VTH(MAX)
	300		700		ms	(ADM811-3T Only)
MANUAL RESET					µs
Minimum Pulsewidth	10
Glitch Immunity		100			ns
RESET/RESET Propagation Delay		0.5			µs
Pull-Up Resistance	10	20	30		kΩ
The Manual Reset Circuit Will Act On
An Input Rising Above	2.3				V	VCC > VTH(MAX), ADM81_L/M
An Input Falling Below	0.7 × VCC		0.8		V	VCC > VTH(MAX), ADM81_L/M
An Input Rising Above			0.25 × VCC		V	VCC > VTH(MAX), ADM81_R/S/T
An Input Falling Below					V	VCC > VTH(MAX), ADM81_R/S/T
RESET Output Voltage
Low (ADM812R/S/T)			0.3		V	VCC = VTH(MAX), ISINK = 1.2 mA
Low (ADM812L/M)			0.4		V	VCC = VTH(MAX), ISINK = 3.2 mA
High (ADM812R/S/T/L/M)	0.8 VCC				V	1.8 V < VCC < VTH(MIN), ISOURCE = 150 µA
Low (ADM811R/S/T)			0.3		V	VCC = VTH(MIN), ISINK = 1.2 mA
Low (ADM811L/M)			0.4		V	VCC = VTH(MIN), ISINK = 3.2 mA
Low (ADM811R/S/T/L/M)			0.3		V	VCC > 1.0 V, ISINK = 50 µA
High (ADM811R/S/T)	0.8 VCC				V	VCC > VTH(MAX), ISOURCE = 500 µA
High (ADM811L/M)	VCC – 1.5				V	VCC > VTH(MAX), ISOURCE = 800 µA

Specifications subject to change without notice.

ABSOLUTE MAXIMUM RATINGS*

(Typical values are at TA = +25°C unless otherwise noted)

Terminal Voltage (With Respect to Ground)

VCC . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . –0.3 V to +6 V
All Other Inputs . . . . . . . . . . . . . . . . .	–0.3 V to VCC + 0.3 V
Input Current
VCC . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . 20 mA
MR . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . 20 mA
Output Current
RESET, RESET . . . . . . . . . . . . . . . .	. . . . . . . . . . . 20 mA
Power Dissipation (TA = +70°C)
RT-4, SOT-143 . . . . . . . . . . . . . . . . .	. . . . . . . . . . 200 mW
Derate by 4 mW/°C above +70°C	330°C/W
θJA Thermal Impedance . . . . . . . . . . .

Operating Temperature Range . . . . . . . . . .	. –40°C to +85°C
Storage Temperature Range . . . . . . . . . . . .	–65°C to +160°C
Lead Temperature (Soldering, 10 sec) . . . . .	. . . . . . .+300°C
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . .	. . . . . . .+215°C
Infrared (15 secs) . . . . . . . . . . . . . . . . . . . .	. . . . . . .+220°C
ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . 3 kV

*Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those listed in the operational sections of this specification is not implied. Exposure to absolute maximum ratings for extended periods of time may affect device reliability.

–2–

REV. 0