19-1756; Rev 1; 7/01 Quad Voltage µP Supervisory Circuit in SOT Package The MAX6339 is a precision quad voltage monitor with microprocessor (µP) supervisory reset timing. The device can monitor up to four system supply voltages without any external components and asserts a single reset if any supply voltage drops below its preset threshold. The device significantly reduces system size and component count while improving reliability compared to separate ICs or discrete components. A variety of factory-trimmed threshold voltages are available to accommodate different supply voltages and tolerances with minimal external component requirements. The selection includes internally fixed options for monitoring +5.0V, +3.3V, +3.0V, +2.5V, +1.8V, and -5.0V supplies with -5% and/or -10% tolerances. The device is also available with one or two user-adjustable threshold options if non-standard thresholds are desired (use external resistor-divider network). The quad monitor provides a single active-low reset output that is asserted when any monitored input is below its associated threshold. The output is open drain with a weak internal pull-up (10µA) to IN2. Reset remains low for a reset timeout period (140ms min) after all voltages are above the selected thresholds. The output is valid as long as either the IN1 or IN2 input voltage remains >1V. The MAX6339 is available in a small 6-pin SOT23 package and operates over the extended (-40°C to +85°C) temperature range. ________________________Applications Telecommunications High-End Printers Features ♦ Monitors Four Power-Supply Voltages ♦ Precision Factory-Set Reset Threshold Options for +5.0V, +3.3V, +3.0, +2.5V, +1.8V, and -5.0V Supplies ♦ User-Adjustable Voltage Monitoring Threshold Options ♦ Low 55µA Supply Current ♦ Open-Drain RESET Output with 10µA Internal Pull-Up ♦ 140ms (min) Reset Timeout Period ♦ RESET Valid to IN1 = 1V or IN2 = 1V ♦ Immune to Short Monitored Supply Transients ♦ No External Components Required ♦ Guaranteed from -40°C to +85°C ♦ Small 6-Pin SOT23 Package Ordering Information PART TEMP. RANGE PIN-PACKAGE MAX6339_UT-T* -40°C TO +85°C 6 SOT23-6 *Insert the desired letter from the Selector Guide into the blank to complete the part number. There is a 2500 piece minimum order increment requirement on the SOT package and these devices are available in tape-and-reel only. Desktop and Network Computers Data Storage Equipment Typical Operating Circuit Networking Equipment Industrial Equipment Set-Top Boxes IN1 SUPPLIES TO BE MONITORED MAX6339 IN2 RESET µP IN3 IN4 GND Pin Configuration appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX6339 General Description MAX6339 Quad Voltage µP Supervisory Circuit in SOT Package ABSOLUTE MAXIMUM RATINGS Terminal Voltage (with respect to GND) Input Voltages (IN_ ) (except -5V)............................-0.3V to +6V RESET.......................................................................-0.3V to +6V Input Voltage (-5V Input) ..........................................-6V to +0.3V Continuous RESET Current .................................................20mA Continuous Power Dissipation (TA = +70°C) 6-pin SOT23 (derate 8.7mW/°C above +70°C).........695.7mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range .............................-65°C to +150°C Junction Temperature ......................................................+150°C Lead Temperature (soldering, 10s) .................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VIN2 = +1V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VIN2 = +3.0V to +3.3V, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER Supply Voltage Range (Notes 2, 3) SYMBOL CONDITIONS VIN2 Input Current IIN_ MIN 1.0 55 115 VIN_ = 0 to VIN2 (input threshold voltage = 1.23V) VTH -0.1 -15 -20 4.50 4.63 4.75 +5V (-10%) threshold 4.25 4.38 4.50 +3.3V (-5%) threshold 3.00 3.08 3.15 +3.3V (-10%) threshold 2.85 2.93 3.00 +3.0V (-5%) threshold 2.70 2.78 2.85 +3.0V (-10%) threshold 2.55 2.63 2.70 +2.5V (-10% ) threshold 2.13 2.19 2.25 +1.8V (-10%) threshold 1.53 1.58 1.62 -5V (+5%) threshold -4.75 -4.63 -4.50 -5V (+10%) threshold -4.50 -4.38 -4.25 1.20 1.23 1.26 VIN decreasing 2 tRD Reset Active Timeout Period tRP VIN = VTH to (VTH - 50mV) (all inputs except –5V) or VIN_ = VTH to (VTH + 50mV) (-5V input only) 140 µA 0.1 +5V (-5%) threshold VHYST Reset Delay V VIN2 = input threshold voltage (input threshold voltage of 3.0V, 3.3V) (Note 4) Threshold Voltage Temperature Coefficient Threshold Hysteresis 5.5 40 VIN_ decreasing VTH UNITS 25 VIN_ increasing Adjustable Threshold MAX VIN_ = input threshold voltage (input threshold voltage of 1.8V, 2.5V, 5V) VIN_ = -5V (input threshold voltage = -5V) Reset Threshold Voltage TYP V V 60 ppm/°C 0.3 % 20 µs 200 _______________________________________________________________________________________ 280 ms Quad Voltage µP Supervisory Circuit in SOT Package (VIN2 = +1V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VIN2 = +3.0V to +3.3V, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL Output Low Voltage VOL CONDITIONS MIN MAX VIN2 = 5V, ISINK = 2mA 0.4 VIN2 = 2.5V, ISINK = 1.2mA 0.4 VIN1 = VIN2 = 1V, ISINK = 50µA 0.4 Output High Voltage Output High Source Current VOH VIN2 > 2.55V, ISOURCE = 6µA (RESET unasserted) Output High Source Current IOH VIN2 > 2.55V (RESET unasserted) Note 1: Note 2: Note 3: Note 4: TYP UNITS V 0.8 × VIN2 V 6 µA 10 100% production tested at TA = +25°C. Limits over temperature guaranteed by design. The device is powered from input IN2. The RESET output is guaranteed to be in the correct state for IN1 or IN2 down to 1V. Monitored voltage (+3.3V, +3.0V) is also the device power supply. Supply current splits as follows: 25µA for the resistordivider (for the monitored voltage) and 30µA for other circuits. Typical Operating Characteristics (VIN2 = +3.0V, TA = +25°C) IIN2 INPUT CURRENT vs. IIN2 VOLTAGE 70 65 60 55 VIN2 = +3.3V 50 45 70 65 60 55 VIN2 = +3.0V 40 75 0.15 MAX6339toc03 80 IIN2 INPUT CURRENT ( µA) 75 MAX6339toc02 80 IIN2 INPUT CURRENT (µA) 85 MAX6339toc01 85 NORMALIZED THRESHOLD ERROR vs. TEMPERATURE NORMALIZED THRESHOLD ERROR (%) IIN2 INPUT CURRENT vs. TEMPERATURE VTH = +5V 0.10 0.05 0 -0.5 VTH = 1.8V -0.10 -0.15 -0.20 -0.25 VIN2 = +3.0V 50 35 -40 -20 0 20 40 TEMPERATURE (°C) 60 80 -0.30 3.0 3.5 4.0 4.5 INPUT VOLTAGE (V) 5.0 5.5 -40 -20 0 20 40 60 80 TEMPERATURE (°C) _______________________________________________________________________________________ 3 MAX6339 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (continued) (VIN2 = +3.0V, TA = +25°C) 70 MAX6339toc05 80 MAX6339toc04 80 RESET PULL-UP AND PULL-DOWN RESPONSE (CL = 47pF) RESET DELAY vs. RESET THRESHOLD OVERDRIVE (IN_ decreasing) 70 60 RESET DELAY (µs) 60 50 RESET ASSERTED ABOVE THIS LINE 40 30 IN_ 100mV/div 50 40 30 20 20 10 10 0 MAX6339toc06 MAXIMUM IN_ TRANSIENT DURATION vs. RESET THRESHOLD OVERDRIVE MAXIMUM IN_ TRANSIENT DURATION (µs) RESET 2V/div 0 0 100 200 300 400 500 600 700 800 900 1000 10µs/div 0 100 200 300 400 500 600 700 800 900 1000 RESET THRESHOLD OVERDRIVE (mV) RESET THRESHOLD OVERDRIVE (mV) RESET TIMEOUT DELAY vs. TEMPERATURE RESET TIMEOUT DELAY 210 MAX6339toc08 MAX6339toc07 215 RESET TIMEOUT DELAY (ms) MAX6339 Quad Voltage µP Supervisory Circuit in SOT Package IN_ 2V/div 205 200 2V/div 195 190 RESET 2V/div 185 180 -40 -20 0 20 40 60 80 200ms/div TEMPERATURE (°C) Pin Description 4 PIN NAME 1 IN1 Input Voltage 1. See Selector Guide for monitored voltages. FUNCTION 2 IN2 Input Voltage 2. See Selector Guide for monitored voltages. IN2 is the power-supply input for the device. 3 IN3 Input Voltage 3. See Selector Guide for monitored voltages. 4 IN4 Input Voltage 4. See Selector Guide for monitored voltages. 5 GND 6 RESET Ground Reset Output, Active Low. RESET goes low when any input goes below its specified threshold. After all inputs are above their threshold voltage, RESET remains low for at least 140ms (minimum) before going high. RESET output is open drain with a weak internal pullup to IN2. _______________________________________________________________________________________ Quad Voltage µP Supervisory Circuit in SOT Package The MAX6339 is a very small, low-power, quad voltage µP supervisory circuit designed to maintain system integrity in multi-supply systems (Figure 1). The device offers several internally trimmed undervoltage threshold options that minimize or eliminate the need for external components. Preset voltage monitoring options for +5.0V, +3.3V, +3.0V, +2.5V, +1.8V, and -5.0V make it ideal for telecommunications, desktop and notebook computers, high-end printers, data storage equipment, and networking equipment applications. The quad monitor/reset includes an accurate bandgap reference, four precision comparators, and a series of internal trimmed resistor-divider networks to set the factory-fixed reset threshold options. The resistor networks scale the specified IN_ reset voltages to match the internal bandgap reference/comparator voltage. Useradjustable threshold options bypass the internal resistor networks and connect directly to one of the comparator inputs (an external resistor-divider network is required for threshold matching). All threshold voltage options, fixed and adjustable, are indicated through a single-letter code in the product number (see Selector Guide). Each of the internal comparators has a typical hysteresis of 0.3% with respect to its reset threshold. This builtin hysteresis improves the monitor’s immunity to ambient noise without significantly reducing threshold accuracy when an input sits at its specified reset voltage. The MAX6339 is also designed to ignore short IN_ transients. See Typical Operating Characteristics for a glitch immunity graph. Applications Information Reset Output The MAX6339 RESET output is asserted low when any of the monitored IN_ voltages drop below its specified reset threshold (or above for -5V option) and remain low for the reset timeout period (140ms minimum) after all inputs exceed their thresholds (Figure 2). The output is open drain with a weak internal pullup to the monitored IN2 supply (10µA typ). For many applications no external pullup resistor is required to interface with other logic devices. An external pullup resistor to any voltage from 0 to +5.5V can overdrive the internal pullup if interfacing to different logic supply voltages (Figure 3). Internal circuitry prevents reverse current flow from the external pullup voltage to IN2. The MAX6339 is normally powered from the monitored IN2 supply when all input voltages are above their specified thresholds. When any supply drops below its threshold, the reset output is asserted and guaranteed to remain low while either IN1 or IN2 is above +1.0V. User-Adjustable Thresholds The MAX6339 offers several monitor options with useradjustable reset thresholds. The threshold voltage at each adjustable IN_ input is typically 1.23V. To monitor a voltage >1.23V, connect a resistor-divider network to the circuit as shown in Figure 4. VINTH = 1.23V x (R1 + R2) / R2 or, solved in terms of R1: R1 = R2 ((VINTH / 1.23V) - 1) Because the MAX6339 has a guaranteed input current of ±0.1µA on its adjustable inputs, resistor values up to 100kΩ can be used for R2 with <1% error. Unused Inputs If some monitor inputs are to be unused, they must be tied to a supply voltage greater in magnitude than their specified threshold voltages. For unused IN3 or IN4 options with positive thresholds (fixed or adjustable), the inputs can be connected directly to the IN2 supply. For unused IN4 options with negative thresholds, the input must be tied to a more negative supply. The IN2 input must always be used for normal operation (device power-supply pin). Unused pins cannot be connected to ground or allowed to float. Negative Voltage Monitoring Beyond -5V The MAX6339 is offered with options to monitor -5V supplies with internally fixed thresholds. To monitor supplies more negative than -5V, a low-impedance resistor-divider network can be used external to the MAX6339 as shown in Figure 5. The current through the external resistor-divider should be greater than the input current for the -5V monitor options. For an input monitor current error of <1%, the resistor-divider current should ≥2mA (for I IN4 = 20µA max). Set R2 = 2.5kΩ. Calculate R1 based on the desired VIN_ reset threshold voltage, using the following formula: R1 = R2 ✕ [(VINTH / VTH ) -1] where R2 ≤ 2.49kΩ, VINTH = desired threshold voltage and VTH is the internal threshold voltage. _______________________________________________________________________________________ 5 MAX6339 Detailed Description MAX6339 Quad Voltage µP Supervisory Circuit in SOT Package ALL DEVICES ARE POWERED FROM IN2 (3.0V/3.3V). RESET IS VALID IF VIN1 OR VIN2 IS GREATER THAN 1V. IN1 (5V) MAX6339 IN1 IN1(5V) PULLUP IN2 (3.3/3V) IN2 RESET NOR GATE TIME OUT (200ms) IN3 (AUX) IN4 (-5V) VREF REFERENCE Figure 1. MAX6339 Functional Diagram 6 _______________________________________________________________________________________ Quad Voltage µP Supervisory Circuit in SOT Package For -VIN = -12V nominal, VINTH = -11.1V, VTH = -4.63V, and R2 = 2.49kΩ, VTH_ R1 = 2.49kΩ ✕ [(-11.1 / -4.63) -1] R1 = 3.48kΩ RESET 90% 10% tRP tRD Figure 2. RESET Output Timing Diagram Power-Supply Bypassing and Grounding The MAX6339 is normally powered from the monitored IN2 supply input. All monitor inputs are immune to short supply transients. If higher immunity is desired in noisy applications, connect 0.1µF bypass capacitors from the IN2 input to ground. Additionally, capacitance can be added to IN1, IN3, and IN4 to increase their noise immunity. +5V IN2 = +3.3V Chip Information TRANSISTOR COUNT: 896 100kΩ PROCESS TECHNOLOGY: BiCMOS IN2 VCC Pin Configuration RESET RESET TOP VIEW IN1 1 MAX6339 IN2 2 MAX6339 6 RESET 5 GND 4 IN4 GND GND IN3 3 Figure 3. Interfacing to Different Logic Supply Voltage SOT23 VINTH R2 R1 -5V R1 R2 VINTH VREF = 1.23V VREF = 1.23V R1 = R2 Figure 4. Setting the Auxiliary Monitor INTH - 1) ( V1.23 R1 = R2 × [( VVINTH )-1] TH Figure 5. Negative Voltage Monitoring Beyond -5V _______________________________________________________________________________________ 7 MAX6339 IN_ VTH_ MAX6339 Quad Voltage µP Supervisory Circuit in SOT Package Selector Guide NOMINAL INPUT VOLTAGE PART IN1 (V) IN2 (V) IN3 (V) IN4 (V) SUPPLY TOLERANCE (%) TOP MARK AAJU MAX6339AUT 5 3.3 2.5 Adj* 10 MAX6339BUT 5 3.3 2.5† Adj* 5 AAJV MAX6339CUT 5 3.3 1.8 Adj* 10 AAJW MAX6339DUT 5 3.3 1.8† Adj* 5 AAJX MAX6339EUT 5 3.0 2.5 Adj* 10 AAJY MAX6339FUT 5 3.0 2.5† Adj* 5 AAJZ AAKA MAX6339GUT 5 3.0 1.8 Adj* 10 MAX6339HUT 5 3.0 1.8† Adj* 5 AAKB MAX6339IUT 5 3.3 2.5 1.8 10 AAKC MAX6339JUT 5 3.3 2.5† 1.8† 5 AAKD MAX6339KUT Adj* 3.3 2.5 Adj* 10 AAKE MAX6339LUT Adj* 3.3 2.5 Adj* 5 AAKF MAX6339MUT 5 3.0 Adj* -5 10 AAKG MAX6339NUT 5 3.0 Adj* -5 5 AAKH MAX6339OUT 5 3.3 Adj* -5 10 AAKI MAX6339PUT 5 3.3 Adj* -5 5 AAKJ *Adjustable voltage based on +1.23V internal threshold. External threshold voltage can be set using an external resistor-divider. †Normal input voltages for 1.8V and 2.5V are specified for 10% tolerances. 8 _______________________________________________________________________________________ 6LSOT.EPS Package Information Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600_____________________ 9 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.