Quad Voltage UP Supervisory Circuit

Preliminary Technical Data FEATURES Low Voltage, High Accuracy, Quad Voltage μP Supervisory Circuit ADM6710 FUNCTIONAL BLOCK DIAGRAM IN1 Accurate monitoring of up to four power supply voltages 5 reset threshold options: 1.8 V to 5 V Monitors down to 0.62 V (1.5% accuracy) 200 ms typical reset timeout Open-drain RESET output (10 μA internal pull-up) Reset output stage: active low, valid to IN1 = 1 V or IN2 = 1 V Low power consumption (35 μA) Power supply glitch immunity Specified from −40º C to +85 ºC 6-lead SOT-23 package ADM6710 IN2, VCC IN2, VCC RESET 200ms TIMEOUT IN3 UVLO IN4 06626-001 APPLICATIONS Microprocessor systems Desktop and notebook computers Controllers Data storage equipment Servers/workstations 0.62V REF Figure 1. GENERAL DESCRIPTION The ADM6710 is a low voltage, high accuracy supervisory circuit. This device monitors up to four system supply voltages. www.DataSheet4U.com If a monitored power supply voltage falls below the minimum voltage threshold, a single active low output asserts, triggering a system reset. The output is open drain with a weak internal pull-up to the monitored IN2 supply (or to VCC in the case of the ADM67109Q) of typically 10 μA. Once all voltages rise above the selected threshold level, the reset signal remains low for the reset timeout period (200 ms typical). The ADM6710 output remains valid as long as IN1 or IN2 exceeds 1V, while for the ADM6710Q the output remains valid as long as VCC exceeds 2 V. The ADM6710 incorporates a variety of internally pretrimmed undervoltage threshold options for monitoring 5.0 V, 3.3 V, 3.0 V, 2.5 V and 1.8 V supply voltages. The device offers up to three adjustable thresholds for monitoring voltages down to 0.62 V. The ADM6710 is available in a 6-lead SOT-23 package and is suitable for use in a variety of voltage monitoring applications. Rev. PrB 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 that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2007 Analog Devices, Inc. All rights reserved. ADM6710 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Specifications..................................................................................... 3 Absolute Maximum ratings............................................................. 4 ESD Caution.................................................................................. 4 Pin Configuration and Function Descriptions............................. 5 Preliminary Technical Data Theory of Operation .........................................................................6 Input Configuration......................................................................6 Reset Output Configuration ........................................................6 Addition Of Manual Reset ...........................................................7 Outline Dimensions ..........................................................................8 Ordering Guide .............................................................................8 Rev. PrB | Page 2 of 8 Preliminary Technical Data SPECIFICATIONS VIN2 = 1 V to 5.5 V, TA = −40ºC to 85ºC, unless otherwise stated. Typical values are VIN2 =3.0 V to 3.3 V, TA = +25ºC. Table 1. Parameter VCC OPERATING VOLTAGE RANGE1 VIN2 OPERATING VOLTAGE RANGE2 INX, INPUT CURRENT Min 2.0 1.0 1.2 Typ Max 5.5 5.5 5.5 40 115 Units V V V μA μA ADM6710 25 55 ICC INPUT CURRENT THRESHOLD VOLTAGE (VTH) ADJUSTABLE THRESHOLD (VTH) RESET THRESHOLD HYSTERESIS (VHYST) RESET THRESHOLD TEMPERATURE COEFFICIENT (TCVTH) INX to RESET DELAY (tRP) RESET TIMEOUT PERIOD (tRP) RESET OUTPUT LOW (VOL) 4.50 4.25 3.00 2.85 2.70 2.55 2.25 2.13 1.62 1.53 0.611 35 4.63 4.38 3.08 2.93 2.78 2.63 2.32 2.19 1.67 1.58 0.620 0.3 60 30 200 0.4 0.2 50 4.75 4.50 3.15 3.00 2.85 2.70 2.38 2.25 1.71 1.62 0.629 μA μA V V V V V V V V V V V %VTH ppm/°C μs ms V V V V V μA Test Conditions ADM6710Q only All devices except ADM6710Q; TA = 0ºC to +85ºC All devices except ADM6710Q; TA = −40ºC to +85ºC INX = nominal input voltage (for 1.8 V, 2.5 V and 5.0 V supplies) IN2 = nominal input voltage (for 3.0 V and 3.3 V supplies). The supply splits into 25 μA for the resistor divider and 30 μA for other circuits. VIN1 = 0 to 0.85 V (for adjustable thresholds) VIN3, V IN4 = 0 to .85 V (for adjustable thresholds) ADM6710Q only; VCC = 5.5 V INX decreasing; 5 V (−5%) INX decreasing; 5 V (−10%) INX decreasing; 3.3 V (−5%) INX decreasing; 3.3 V (−10%) INX decreasing; 3.0 V (−5%) INX decreasing; 3.0 V (−10%) INX decreasing; 2.5 V (−5%) INX decreasing; 2.5 V (−10%) INX decreasing; 1.8 V (−5%) INX decreasing; 1.8 V (−10%) INX decreasing INX increasing relative to INX decreasing VIN falling at 10 mV/μs from VTH to VTH − 50 mV VIN2, VCC = 5 V, ISINK = 2 mA VIN2, VCC = 2.5 V, ISINK = 1.2 mA VIN2 = 1.0 , ISINK = 50 μA, TA = 0 ºC to +85 ºC VCC ≥2.0 V, ISOURCE=6 μA, RESET deasserted (ADM6710Q only) VIN2 ≥2.0 V, ISOURCE=6 μA, RESET deasserted VIN2 ≥ 2.0 V, RESET deasserted 140 280 0.3 0.4 0.3 RESET OUTPUT HIGH (VOH) RESET OUTPUT HIGH SOURCE CURRENT (IOH) 1 2 0.8 × VCC 0.8 × VCC 10 Note that the ADM6710Q is powered from VCC. The RESET output is guaranteed to be in the correct state for IN1 or IN2 down to 1 V. Rev. PrB | Page 3 of 8 ADM6710 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter VCC, INX, RESET to GND Continuous RESET Current Continuous Power Dissipation Storage Temperature Range Operating Temperature Range Lead Temperature (10 sec) Junction Temperature Rating −0.3 V to +6 V 20 mA 450 mW −65°C to +125°C −40°C to +85°C 300°C 150°C Preliminary Technical Data Stresses above 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 section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ESD CAUTION Rev. PrB | Page 4 of 8 Preliminary Technical Data PIN CONFIGURATION AND FUNCTION DESCRIPTIONS IN1 1 6 ADM6710 RESET GND 06626-002 IN1 1 6 RESET GND IN4 06626-003 ADM6710 IN2 2 IN3 3 TOP VIEW (Not to Scale) 5 ADM6710Q VCC 2 IN3 3 TOP VIEW (Not to Scale) 5 4 IN4 4 Figure 2. Table 3. Pin Function Descriptions Pin No. 1 2 3 4 5 6 Mneumonic IN1 IN2 VCC IN3 IN4 GND RESET Description Input Voltage 1. Input Voltage 2. IN2 is the power supply input for the ADM6710. VCC is the power supply input for the ADM6710Q. It is not a monitored input. Input Voltage 3. Input Voltage 4. Ground. RESET goes low when an input drops below the specified threshold. Once all inputs rise above the threshold voltage, RESET remains low for 200 ms (typical) before going high. The RESET output is open drain with a weak internal pull-up to IN2 or, in the case of the ADM6710Q to VCC, typically 10 μA. Rev. PrB | Page 5 of 8 ADM6710 THEORY OF OPERATION The ADM6710 is a compact, low power supervisory circuit capable of monitoring up to four voltages in multivoltage applications. If a monitored power supply voltage falls below the minimum voltage threshold, a single active low output asserts, triggering a system reset. The ADM6710 includes several voltage threshold options for monitoring 5.0 V, 3.3 V, 3.0 V, 2.5 V and 1.8 V supplies. It also provides up to three adjustable thresholds for monitoring voltages down to 0.62 V. See the Ordering Guide section for a list and description of all options available. The ADM6710 includes precision comparators, an accurate band gap reference, and a series of internally-trimmed resistor divider networks to set the factory-fixed reset threshold options. The resistor networks scale the specified INx reset voltages to match the internal band gap reference/comparator voltage. Adjustable threshold options bypass the internal resistor networks and connect directly to one of the comparator inputs. External resistor divider networks must be used to scale voltages down for monitoring at the adjustable inputs. The ADM6710Q provides a separate unmonitored power supply input (VCC) and three adjustable voltage inputs. The internal comparators each typically have a hysteresis of 0.3% with respect to its reset threshold. This built-in hysteresis improves the device’s immunity to ambient noise without noticeably reducing the threshold accuracy. The ADM6710 is unaffected by short input transients. ADM6710 IN1 MONITORED SUPPLIES IN2 IN3 IN4 GND 06626-004 Preliminary Technical Data VINTH R1 R2 06626-006 VREF = 0.62V Figure 4. Setting the Adjustable Monitor The ADM6710Q contains an internal voltage clamp at each of the adjustable voltage inputs. Input voltages greater than 1.5 V induce a higher input current. The ADM6710 is normally powered from the monitored IN2, or VCC in the case of the ADM6710Q. Monitored inputs are resistant to short power supply glitches. To increase noise immunity in noisy applications, place a 0.1 μF capacitor between the IN2 input and ground. Adding capacitance to IN1, IN3, and IN4 also improves noise immunity. Do not a