MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages General Description The MAX6457-MAX6460 high supply voltage, low-power voltage monitors operate over a 4V to 28V supply voltage range. Each device includes a precision bandgap reference, one or two low-offset voltage comparators, internal threshold hysteresis, power-good or reset timeout options, and one or two high-voltage open-drain outputs. Two external resistors (three for window detection) set the trip threshold voltages. The MAX6457 is a single voltage monitor for undervoltage or overvoltage detection. A logic-based clear input either latches the output for overvoltage applications or allows the device to operate in transparent mode. The MAX6458 includes two comparators (one overvoltage and one undervoltage) for window detection and a single output to indicate if the monitored input is within an adjustable voltage window. The MAX6459 includes dual overvoltage/ undervoltage comparators with two independent comparator outputs. Use the MAX6459 as a window comparator with separate undervoltage and overvoltage outputs or as two independent, single voltage monitors. The MAX6460 includes a single comparator and an internal reference, and can also accept an external reference. The inverting and noninverting inputs of the comparator are externally accessible to support positive or negative voltage monitors and to configure the device for active-high or activelow output logic. The MAX6457/MAX6458 offer fixed timing options as a voltage detector with a 50s typical delay or as a reset circuit with a 90ms minimum reset timeout delay. The monitored input must be above the adjusted trip threshold (or within the adjusted voltage window for the MAX6458) for the selected timeout period before the output changes state. The MAX6459/MAX6460 offer only a fixed 50s timeout period. Internal threshold hysteresis options (0.5%, 5%, and 8.3% for the MAX6457/MAX6458/ MAX6459, and 0.5% for the MAX6460) reduce output chatter in noise-sensitive applications. Each device is available in a small SOT23 package and specified over the extended temperature range of -40C to +125C. Applications Undervoltage Monitoring/Shutdown Overvoltage Monitoring/Protection Window Voltage Detection Circuitry Multicell Battery-Stack Powered Equipment Notebooks, eBooks Automotive Industrial Telecom Networking 19-2048; Rev 7; 7/17 Benefits and Features Wide Supply Voltage Range, 4V to 28V Internal 2.25V 2.5% Reference Low Current (3.5A, typ at 12V) Open-Drain n-Channel Output (28V Compliant) Internal Threshold Hysteresis Options (0.5%, 5%, 8.3%) Two IN-to-OUT Timeout Period Options (50s, 150ms) Internal Undervoltage Lockout Immune to Short Voltage Transients Small SOT23 Packages Few External Components Fully Specified from -40C to +125C AEC-Q100 Qualified (MAX6459UTA/V+ only) Ordering Information PART MAX6457UKD_ _-T MAX6458UKD_ _-T MAX6459UTA/V-T MAX6459UT_/V+ MAX6460UT-T TEMP RANGE -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C PIN-PACKAGE 5 SOT23 5 SOT23 6 SOT23 6 SOT23 6 SOT23 Note: The MAX6457/MAX6458/MAX6459 are available with factory-trimmed internal hysteresis options. The MAX6457 and MAX6458 offer two fixed timing options. Select the desired hysteresis and timing options using Table 1 or the Selector Guide at the end of the data sheet, and enter the corresponding letters and numbers in the part number by replacing "_ _" or "_". These devices are offered in tape-and-reel only and must be ordered in 2500-piece increments. Devices are available in both leaded and lead(Pb)-free/RoHS compliant packaging. Specify lead(Pb)-free by replacing "-T" with "+T" when ordering. /V denotes an automotive qualified part. Pin Configurations appears at end of data sheet. Typical Operating Circuit BATTERY CHARGER +21V (NOMINAL) IN OUT DC-DC CONVERTER SHDN VCC 5-CELL Li+ BATTERY STACK MAX6457 R1 IN+ OUT R2 GND CLEAR RPULLUP LOAD MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Absolute Maximum Ratings VCC, OUT, OUTA, OUTB, CLEAR to GND.........-0.3V to +30.0V IN+, IN- to GND......................................... -0.3V to (VCC + 0.3V) REF to GND............-0.3V to the lower of +6V and (VCC + 0.3V) Input Currents (VCC, IN+, IN-)............................................20mA Sink Current (OUT, OUTA, OUTB)......................................20mA Continuous Power Dissipation (TA = +70C) 5-Pin SOT23 (derate 7.1 mW/C above +70C)..........571mW 6-Pin SOT23 (derate 8.7 mW/C above +70C)..........696mW Junction Temperature.......................................................+150C Operating Temperature Range.......................... -40C to +125C Storage Temperature Range............................. -65C to +150C Lead Temperature (soldering, 10s).................................. +300C Soldering Temperature (reflow) Lead(Pb)-free...............................................................+260C Containing lead (Pb).....................................................+240C 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 (VCC = 4V to 28V, TA = -40C to +125C, unless otherwise specified. Typical values are at TA = +25C.) (Note 1) PARAMETER Operating Voltage Range Supply Current SYMBOL VCC ICC VTH+ CONDITIONS (Note 2) VTH- 4 7.5 VCC = 24V, no load 6.5 12.5 1.228 1.255 VIN rising TA = -40C to +85C, VCC 4V 1.195 TA = +85C to +125C, VCC 4V VIN falling MAX645_U_D_B 1.255 1.180 1.255 TA = +85C to +125C 1.155 1.255 TA = -40C to +85C 1.133 1.194 TA = +85C to +125C 1.111 1.194 TA = -40C to +85C 1.093 1.151 TA = +85C to +125C 1.071 1.151 0.5 MAX64_ _U_D_B 5 MAX64_ _U_D_C 8.3 IIN VIN = 1.25V, VCC = +28V www.maximintegrated.com 1.170 TA = -40C to +85C MAX64_ _U_D_A IN Leakage Current CLEAR Input Logic Voltage (MAX6457) V %VTH+ VCC V -55 +55 nA MAX645_UKD0_ MAX6459UT_ MAX6460UT MAX6457 and MAX6458 only, D3 option A 0 50 90 VCC rising from GND to VCC 4V in less than 1s (Note 3) 150 s 210 2 VIL VIH V 3.5 (Note 2) Startup Time 28 VCC = 12V, no load VIN tTP UNITS 5 IN Operating Voltage Range OUT Timeout Period MAX 2 MAX645_U_D_C Threshold Voltage Hysteresis TYP VCC = 5V, no load MAX645_U_D_A Threshold Voltage MIN ms 0.4 2 ms V Maxim Integrated 2 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Electrical Characteristics (continued) (VCC = 4V to 28V, TA = -40C to +125C, unless otherwise specified. Typical values are at TA = +25C.) (Note 1) PARAMETER Output Voltage Low SYMBOL VOL CONDITIONS MIN TYP MAX VCC 1.5V, ISINK = 250A, OUT asserted, TA = -40C to +85C 0.4 VCC 4.0V, ISINK = 1mA, OUT asserted, TA = -40C to +125C 0.4 500 UNITS V Output Leakage Current ILKG VCC = 5V, VOUT = 28V (Note 4) nA Output Short-Circuit Sink ISC OUT asserted, OUT = VCC 10 mA REF = GND 7 mA MAX6460 Reference Short-Circuit Current Reference Output Voltage VREF 2.183 2.25 2.303 TA = +85C to +125C 2.171 2.25 2.303 Sourcing: 0 IREF 100A, sinking: 0 |IREF| 300nA Load Regulation Input Offset Voltage TA = -40C to +85C VOFFSET 50 -4.5 Input Hysteresis Input Bias Current Input Offset Current V/A +4.5 6 IBIAS VIN+ = 1.4V, VIN- = 1V -25 IOFFSET Common-Mode Voltage Range CMVR Common-Mode Rejection Ratio CMRR Comparator Power-Supply Rejection Ratio PSRR 2 VIN+ = VIN- = 1.4V mV mV +25 0 V nA pA 1.4 V 80 dB 80 dB Note 1: Devices are production tested at TA = +25C. Overtemperature limits are guaranteed by design. Note 2: IN voltage monitoring requires that VCC 4V, but OUT remains asserted in the correct undervoltage lockout state for VCC down to 1.5V. Note 3: Startup time is the time required for the internal regulator and reference to reach specified accuracy after the monitor is powered up from GND. Note 4: The open-drain output can be pulled up to a voltage greater than VCC but cannot exceed +28V. www.maximintegrated.com Maxim Integrated 3 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Typical Operating Characteristics (GND = 0, RPULLUP = 10k, and TA = +25C, unless otherwise noted.) TA = +125C TA = +25C 4 TA = -40C 2 0 10 4 16 22 28 1.21 VTH- (FALLING) 1.19 1.17 1.15 1.13 1.11 -40 -25 -10 5 20 35 50 65 80 95 110 125 VCC (V) TRIP THRESHOLD VOLTAGE vs. TEMPERATURE (8.3% HYSTERESIS) 1.23 1.21 1.21 VTH+ (RISING) 1.19 1.17 1.15 VTH- (FALLING) 1.13 1.11 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) 1.17 OUTPUT LOW VOLTAGE vs. OUTPUT SINK CURRENT 100,000 10,000 TA = +125C 1000 VOL (mV) VTH+ (RISING) 1.19 TA = +25C 100 TA = -40C 10 1.15 VTH- (FALLING) 1.13 1.11 1.23 TEMPERATURE (C) MAX6457-60 toc04 TRIP THRESHOLD VOLTAGE (V) 1.25 1.25 MAX6457-60 toc03 1.23 TRIP THRESHOLD VOLTAGE vs. TEMPERATURE (5% HYSTERESIS) -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) www.maximintegrated.com MAX6457-60 toc05 6 VTH+ (RISING) TRIP THRESHOLD VOLTAGE (V) ICC (A) 8 TRIP THRESHOLD VOLTAGE vs. TEMPERATURE (0.5% HYSTERESIS) MAX6457-60 toc02 10 1.25 TRIP THRESHOLD VOLTAGE (V) MAX6457-60 toc01 12 SUPPLY CURRENT vs. SUPPLY VOLTAGE 1 0.1 VCC = 12V 0.01 0.1 1 10 100 ISINK (mA) Maxim Integrated 4 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Typical Operating Characteristics (continued) (GND = 0, RPULLUP = 10k, and TA = +25C, unless otherwise noted.) 11 VCC = 5V 10 VCC = 24V MAX6457UKD0 1800 TA = +125C 1600 1400 1200 1000 800 600 TA = +25C 400 0.1 9 8 1 2000 TA = -40C 200 -40 -25 -10 5 20 35 50 65 80 95 110 125 0.01 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) 8 12 16 20 24 28 VCC (V) 10 MAX6457-60 toc09 INPUT LEAKAGE CURRENT vs. TEMPERATURE VIN = 1.25V 8 200 6 IIN (nA) MAXIMUM TRANSIENT DURATION (s) 250 150 100 4 2 OUT ASSERTED LOW ABOVE THIS LINE 50 0 4 TEMPERATURE (C) MAXIMUM TRANSIENT DURATION vs. INPUT OVERDRIVE 300 0 MAX6457-60 toc10 12 MAX6457UKD3 10 tTP (ms) ISC (mA) 13 100 OUTPUT FALL TIME vs. SUPPLY VOLTAGE MAX6457-60 toc08 14 1000 OUTPUT FALL TIME (ns) VCC = 12V TIMEOUT PERIOD vs. TEMPERATURE MAX6457-60 toc07 MAX6457-60 toc06 15 OUTPUT SHORT-CIRCUIT SINK CURRENT vs. TEMPERATURE 0 1 10 100 INPUT OVERDRIVE (VTH- - VIN+) (mV) www.maximintegrated.com 1000 -2 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) Maxim Integrated 5 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Pin Description PIN MAX6457 MAX6458 MAX6459 MAX6460 NAME FUNCTION MAX6457: Open-Drain Monitor Output. OUT requires an external pullup resistor. OUT asserts low for VCC between 1.5V and 4V. OUT asserts low when VIN+ drops below VTH- and goes high after the timeout period (tTP) when VIN+ exceeds VTH+. 1 1 -- 1 OUT MAX6458: Open-Drain Monitor Output. OUT requires an external pullup resistor. OUT asserts low for VCC between 1.5V and 4V. OUT asserts low when VIN+ drops below VTH- or when VIN- exceeds VTH+. OUT goes high after the timeout period (tTP) when VIN+ exceeds VTH+ and VIN- drops below VTH-. MAX6460: Open-Drain Monitor Output. OUT requires an external pullup resistor. OUT asserts low for VCC between 1.5V and 4V. OUT asserts low when VIN+ drops below VIN-. OUT goes high when VIN+ is above VIN-. -- -- 1 -- OUTA Open-Drain Monitor A Undervoltage Output. OUTA requires an external pullup resistor. OUTA goes low when VIN+ drops below VTH- and goes high when VIN+ exceeds VTH+. OUTA also goes low for VCC between 1.5V and 4V. -- -- 5 -- OUTB Open-Drain Monitor B Overvoltage Output. OUTB requires an external pullup resistor. OUTB goes low when VIN- exceeds VTH+ and goes high when VIN- drops below VTH-. OUTB also goes low when VCC drops below 4V. 2 2 2 2 GND Ground 3 3 3 3 IN+ Adjustable Undervoltage Monitor Threshold Input. Noninverting input for MAX6460. -- 4 4 4 IN- Adjustable Overvoltage Monitor Threshold Input. Inverting input for MAX6460. 4 -- -- -- CLEAR Clear Input. For VIN+ > VTH+, drive CLEAR high to latch OUT high. Connect CLEAR to GND to make the latch transparent. CLEAR must be low when powering up the device. Connect CLEAR to GND when not used. -- -- -- 5 REF Reference. Internal 2.25V reference output. Connect REF to IN+ through a voltage divider for active-low output. Connect REF to INthrough a voltage divider for active-high output. REF can source up to 100A and sink up to 300nA. Leave REF floating when not used. REF output is stable with capacitive loads from 0 to 50pF or greater than 1F. 5 5 6 6 VCC Supply Voltage www.maximintegrated.com Maxim Integrated 6 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Functional Diagrams VCC VCC MAX6458 IN+ UV MAX6457 IN+ TIMEOUT OPTION HYSTERESIS OPTION LATCH OUT TIMEOUT OPTION INOV HYSTERESIS OPTION 1.228V OUT CLEAR 1.228V "UV": UNDERVOLTAGE "OV": OVERVOLTAGE GND GND Figure 1. MAX6457 Functional Diagram Figure 2. MAX6458 Functional Diagram VCC IN+ VCC MAX6459 OUTA UV IN+ OUT IN- INHYSTERESIS OPTION 1.228V OUTB OV REF MAX6460 2.25V "UV": UNDERVOLTAGE "OV": OVERVOLTAGE GND GND Figure 3. MAX6459 Functional Diagram www.maximintegrated.com Figure 4. MAX6460 Functional Diagram Maxim Integrated 7 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Detailed Description R4 VREFD = VREF R3+R4 Each of the MAX6457-MAX6460 high-voltage (4V to 28V), low-power voltage monitors include a precision bandgap reference, one or two low-offset-voltage comparators, internal threshold hysteresis, internal timeout period, and one or two high-voltage open-drain outputs. Programming the Trip Voltage (VTRIP) Two external resistors set the trip voltage, VTRIP (Figure 5). VTRIP is the point at which the applied voltage (typically VCC) toggles OUT. The MAX6457/MAX6458/MAX6459/ MAX6460's high input impedance allows large-value resistors without compromising trip-voltage accuracy. To minimize current consumption, select a value for R2 between 10k and 1M, then calculate R1 as follows: V = R1 R2 TRIP -1 VREFD where VREF = reference output voltage (2.25V, typ), VREFD = divided reference, VTRIP = desired trip threshold in (in volts). For an active-low power-good output, connect the resistor divider R1 and R2 to the inverting input and the reference-divider network to the noninverting input. Alternatively, connect an external reference less than 1.4V to either input. V R1 = R2 TRIP -1 V TH VTRIP VCC R1 VCC MAX6457- MAX6460 R1 IN+ R2 OUT (OUTA FOR MAX6459) RPULLUP IN+ REF OUT (OUTA) R2 GND Figure 5b. Programming the MAX6460 Trip Voltage where VTRIP = desired trip voltage (in volts), VTH = threshold trip voltage (VTH+ for overvoltage detection or VTH- for undervoltage detection). www.maximintegrated.com OUT IN- R4 VTRIP = VTH R1 + R2 R2 Use the MAX6460 voltage reference (REF) to set the trip threshold by connecting IN+ or IN- through a voltage divider (within the inputs common-mode voltage range) to REF. Do not connect REF directly to IN+ or IN- since this violates the input common-mode voltage range. Small leakage currents into the comparators inputs allows use of large value resistors to prevent loading the reference and affecting its accuracy. Figure 5b shows an active-high power-good output. Use the following equation to determine the resistor values when connecting REF to IN-: MAX6460 OUT R3 VREFD GND Figure 5a. Programming the Trip Voltage RPULLUP VCC VHYST VIN+ VTH+ VTH- VCC VOUT 0 tTP tTP Figure 6. Input and Output Waveforms (Noninverting Input Varied) Maxim Integrated 8 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages >VTH+ IN+ <VTH- VCC CLEAR 0 VCC OUT tTP tTP tTP 0 Figure 7. Timing Diagram (MAX6457) Hysteresis Hysteresis adds noise immunity to the voltage monitors and prevents oscillation due to repeated triggering when VIN is near the threshold trip voltage. The hysteresis in a comparator creates two trip points: one for the rising input voltage (VTH+) and one for the falling input voltage (VTH-). These thresholds are shown in Figure 6. BATTERY CHARGER The internal hysteresis options of the MAX6457/MAX6458/ MAX6459 are designed to eliminate the need for adding an external hysteresis circuit. 5-CELL Li+ BATTERY STACK Timeout Period The timeout period (tTP) for the MAX6457 is the time from when the input (IN+) crosses the rising input threshold (VTH+) to when the output goes high (see Figures 6 and 7). For the MAX6458, the monitored voltage must be in the "window" before the timeout starts. The MAX6459 and MAX6460 do not offer the extended timeout option (150ms). The extended timeout period is suitable for overvoltage protection applications requiring transient immunity to avoid false output assertion due to noise spikes. Latched-Output Operation The MAX6457 features a digital latch input (CLEAR) to latch any overvoltage event. If the voltage on IN+ (VIN+) is below the internal threshold (VTH-), or if VCC is below www.maximintegrated.com +21V IN OUT DC-DC CONVERTER SHDN VCC R1 MAX6457- MAX6460 IN+ R2 RPULLUP LOAD OUT (OUTA FOR MAX6459) GND Figure 8. Undervoltage Lockout Typical Application Circuit 4V, OUT remains low regardless of the state of CLEAR. Drive CLEAR high to latch OUT high when VIN+ exceeds VTH+. When CLEAR is high, OUT does not deassert if VIN+ drops back below VIN-. Toggle CLEAR to deassert OUT. Drive CLEAR low to make the latch transparent (Figure 7). CLEAR must be low when powering up the MAX6457. To initiate self-clear at power-up, add a 100k pullup resistor from CLEAR to VCC and a 1F capacitor from CLEAR to GND to hold CLEAR low. Connect CLEAR to GND when not used. See Figure 9. Maxim Integrated 9 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages VSUPPLY VSUPPLY R1 FUSE VCC VCC LOAD IN+ 100k MAX6457- MAX6460 R2 R3 MAX6457- MAX6460 R1 LOAD OUT (OUTA FOR MAX6459) CLEAR 1F RPULLUP SCR OUT (OUTA FOR MAX6459) IN+ R2 GND GND Figure 9. Overvoltage Shutdown Circuit (with External Pass MOSFET) Figure 10. Overvoltage Shutdown Circuit (with SCR Fuse) Applications Information Window Detection Undervoltage Lockout Figure 8 shows the typical application circuit for detecting an undervoltage event of a 5-cell Li+ battery stack. Connect OUT of the MAX6457/MAX6458/MAX6460 (OUTA of the MAX6459) to the shutdown input of the DCDC converter to cut off power to the load in case of an undervoltage event. Select R1 and R2 to set the trip voltage (see the Programming the Trip Voltage (VTRIP) section). When the voltage of the battery stack decreases so that VIN+ drops below VTH- of the MAX6457-MAX6460, then OUT (OUTA) goes low and disables the power supply to the load. When the battery charger restores the voltage of the 5-cell stack so that VIN+ > VTH+, OUT (OUTA) goes high and the power supply resumes driving the load. The MAX6458/MAX6459 include undervoltage and overvoltage comparators for window detection (Figures 2 and 3). The circuit in Figure 11 shows the typical configuration for this application. For the MAX6458, OUT asserts high when VCC is within the selected "window." When VCC falls below the lower limit of the window (VTRIPLOW) or exceeds the upper limit (VTRIPHIGH), OUT asserts low. The MAX6459 features two independent open-drain outputs: OUTA (for undervoltage events) and OUTB (for overvoltage events). When VCC is within the selected window, OUTA and OUTB assert high. When VCC falls below VTRIPLOW, OUTA asserts low while OUTB remains VCC Overvoltage Shutdown The MAX6457-MAX6460 are ideal for overvoltage shutdown applications. Figure 9 shows a typical circuit for this application using a pass P-channel MOSFET. The MAX6457-MAX6460 are powered directly from the system voltage supply. Select R1 and R2 to set the trip voltage (see the Programming the Trip Voltage (VTRIP) section). When the supply voltage remains below the selected threshold, a low logic level on OUT (OUTB for MAX6459) turns on the p-channel MOSFET. In the case of an overvoltage event, OUT (OUTB) asserts high, turns off the MOSFET, and shuts down the power to the load. Figure 10 shows a similar application using a fuse and a silicon-controlled rectifier (SCR). An overvoltage event turns on the SCR and shorts the supply to ground. The surge of current through the short circuit blows the fuse and terminates the current to the load. Select R3 so that the gate of the SCR is properly biased when OUT (OUTB) goes high impedance. www.maximintegrated.com VCC VCC RPULLUP OUT MAX6458 ONLY R1 OUT VCC IN+ MAX6458 MAX6459 R2 RPULLUP INOUTA OUTA OUTB MAX6459 ONLY OUTB R3 GND RPULLUP Figure 11. Window Detection Maxim Integrated 10 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages high. When VCC exceeds VTRIPHIGH, OUTB asserts low while OUTA remains high. VTRIPLOW and VTRIPHIGH are given by the following equations: R VTRIPLOW = V TH- TOTAL R2 + R3 R VTRIPHIGH = VTH+ TOTAL R3 Example Calculations for Window Detection The following is an example for calculating R1, R2, and R3 of Figure 11 for window detection. Select the upper and lower trip points (VTRIPHIGH and VTRIPLOW). VCC = 21V VTRIPHIGH = 23.1V VTRIPLOW = 18.9V where RTOTAL = R1 + R2 + R3. Use the following steps to determine the values for R1, R2, and R3. For 5% hysteresis, VTH+ = 1.228 and VTH- = 1.167. 1) Choose RTOTAL = 4.2M = R1 + R2 + R3 2) Calculate R3 1) Choose a value for RTOTAL, the sum of R1, R2, and V TH+ x R TOTAL (1.228V)(4.2M) R3. Because the MAX6458/MAX6459 have very high = R3 = V TRIPHIGH 23.1V input impedance, RTOTAL can be up to 5M. 2) Calculate R3 based on RTOTAL and the desired upper trip point: = 223.273k 3) Calculate R2 V x R TOTAL R3 = TH+ V TRIPHIGH 3) Calculate R2 based on RTOTAL, R3, and the desired lower trip point: VCC MAX6457- MAX6460 V TH- x R TOTAL - R3 V TRIPLOW R2 = VOUT (UP TO 28V) VCC (4V TO 28V) 4) Calculate R1 based on RTOTAL, R3, and R2: R1 = RTOTAL - R2 - R3 RPULLUP OUT/ OUTA/ OUTB OUT/ OUTA/ OUTB GND Figure 13. Interfacing to Voltages Other than VCC VCC VCC VMON VCC R1 IN+ MAX6457- MAX6460 R2 IN- RPULLUP OUT (OUTA FOR MAX6459) OUT (OUTA) REF RPULLUP MAX6460 OUT OUT R1 IN+ GND VCC GND R2 VNEG Figure 12. Monitoring Voltages Other than VCC www.maximintegrated.com Figure 14. Monitoring Negative Voltages Maxim Integrated 11 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Table 1. Factory-Trimmed Internal Hysteresis and Timeout Period Options PART SUFFIX TIMEOUT OPTION HYSTERESIS OPTION (%) 0A 50s 0.5 0B 50s 5 0C 50s 8.3 3A 150ms 0.5 3B 150ms 5 3C 150ms 8.3 A 50s 0.5 MAX6457UKD_ _ -T MAX6458UKD_ _ -T MAX6459UT_ -T MAX6460UT-T B 50s 5 C 50s 8.3 N/A 50s 0.5 Selector Guide PIN COUNT LATCHED OUTPUT NUMBER OF OUTPUTS HYSTERESIS (%VTH+) TIMEOUT PERIOD TOP MARK COMPARATORS MAX6457UKD0A-T 5 u 1 0.5 50s AEAA 1 MAX6457UKD3A-T 5 u 1 0.5 150ms AANN 1 MAX6457UKD0B-T 5 u 1 5 50s AANL 1 MAX6457UKD3B-T 5 u 1 5 150ms AANO 1 MAX6457UKD0C-T 5 u 1 8.3 50s AANM 1 MAX6457UKD3C-T 5 u 1 8.3 150ms ADZZ 1 MAX6458UKD0A-T 5 -- 1 0.5 50s AANP 2 MAX6458UKD3A-T 5 -- 1 0.5 150ms AANS 2 MAX6458UKD0B-T 5 -- 1 5 50s AANQ 2 MAX6458UKD3B-T 5 -- 1 5 150ms AEAB 2 MAX6458UKD0C-T 5 -- 1 8.3 50s AANR 2 MAX6458UKD3C-T 5 -- 1 8.3 150ms AANT 2 MAX6459UTA-T 6 -- 2 0.5 50s ABML 2 MAX6459UTB-T 6 -- 2 5 50s ABEJ 2 MAX6459UTC-T 6 -- 2 8.3 50s ABMM 2 MAX6460UT-T 6 -- 1 0.5 50s ABEG 1 MAX6459UTA/V-T 6 -- 2 0.5 50s ACRY 2 PART www.maximintegrated.com Maxim Integrated 12 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Interfacing to Voltages Other than VCC V x R TOTAL R2 = TH- R3 V TRIPLOW The open-drain outputs of the MAX6457-MAX6460 allow the output voltage to be selected independent of VCC. For systems requiring an output voltage other than VCC, connect the pullup resistor between OUT, OUTA, or OUTB and any desired voltage up to 28V (see Figure 13). (1.167V) (4.2M ) - 223.273k 18.9V = 36.06k Monitoring Negative Voltages 4) Calculate R1 Figure 14 shows the typical application circuit for monitoring negative voltages (VNEG) using the MAX6460. Select a value for R1 between 25k and 1M. Use the following equation to select R2: R1 = R TOTAL - R2 - R3 = 4.2M - 223.273k - 36.06k = 3.94067M Monitoring Voltages Other than VCC R2 = R1x The MAX6457-MAX6460 can monitor voltages other than VCC (Figure 12). Calculate VTRIP as shown in the Programming the Trip Voltage (VTRIP) section. The monitored voltage (VMON) is independent of VCC. VIN+ must be within the specified operating range: 0 to VCC. -VNEG VREF where VREF = 2.25V and VNEG < 0. VIN+ must always be within the specified operating range: 0 to VCC. Pin Configurations TOP VIEW OUT 1 GND 2 5 VCC MAX6457 IN+ 3 OUT 1 GND 2 4 CLEAR OUTA 1 GND 2 MAX6459 IN+ 3 SOT23 www.maximintegrated.com VCC 4 IN- 6 VCC 5 REF 4 IN- MAX6458 IN+ 3 SOT23 5 SOT23 6 VCC OUT 1 5 OUTB GND 2 4 IN- MAX6460 IN+ 3 SOT23 Maxim Integrated 13 MAX6457-MAX6460 Chip Information PROCESS: BiCMOS www.maximintegrated.com High-Voltage, Low-Current Voltage Monitors in SOT Packages Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 5 SOT23 U5+1 21-0057 90-0174 6 SOT23 U6+1 21-0058 90-0175 Maxim Integrated 14 MAX6457-MAX6460 High-Voltage, Low-Current Voltage Monitors in SOT Packages Revision History REVISION NUMBER REVISION DATE PAGES CHANGED 0 7/02 Initial release 1 6/03 Updated the Pin Description and Detailed Description sections. 2 12/05 Added lead-free notation to Ordering Information. 3 1/07 Updated the Pin Description and Figures 5a, 9, 12. 4 3/09 Updated the Programming the Trip Voltage (VTRIP) section. 8 5 7/12 Updated the Package Information table. 14 6 12/12 Added MAX6459UT_/V+ to Ordering Information 1 7 7/17 Added AEC-Q100 to Benefits and Features section and /V part to Ordering Information and Selector Guide DESCRIPTION -- 6, 8 1 6, 8, 10, 11, 13-16 1, 12 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated's website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. (c) 2017 Maxim Integrated Products, Inc. 15 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Maxim Integrated: MAX6457UKD3C+T MAX6457UKD0A+T MAX6457UKD0B+T MAX6457UKD0C+T MAX6457UKD3A+T MAX6457UKD3B+T MAX6458UKD0A+T MAX6458UKD0B+T MAX6458UKD0C+T MAX6458UKD3A+T MAX6458UKD3B+T MAX6458UKD3C+T MAX6459UTA+T MAX6459UTB+T MAX6459UTC+T MAX6460UT+T MAX6459UTA/V+T MAX6458UKD0B