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19-0099; Rev 5; 4/06
+3V Voltage Monitoring, Low-Cost P Supervisory Circuits
General Description
The MAX706P/R/S/T, MAX706AP/AR/AS/AT, and MAX708R/S/T microprocessor (P) supervisory circuits reduce the complexity and number of components required to monitor +3V power-supply levels in +3V to +5V P systems. These devices significantly improve system reliability and accuracy compared to separate ICs or discrete components. The MAX706P/R/S/T and MAX706AP/AR/AS/AT supervisory circuits provide the following four functions: 1) A reset output during power-up, power-down, and brownout conditions. 2) An independent watchdog output that goes low if the watchdog input has not been toggled within 1.6s. 3) A 1.25V threshold detector for power-fail warning, low-battery detection, or for monitoring a power supply other than the main supply. 4) An active-low, manual-reset input. The only difference between the MAX706R/AR, MAX706S/AS, and MAX706T/AT is the reset-threshold voltage levels, which are 2.63V, 2.93V, and 3.08V, respectively. All have active-low reset output signals. The MAX706P/AP are identical to the MAX706R/AR, except the reset output signal is active-high. The watchdog timer function for the MAX706AP/AR/AS/AT disables when the WDI input is left open or connected to a high-impedance state of a low-leakage tri-state output. The MAX708R/S/T provide the same functions as the MAX706R/S/T and MAX706AR/AS/AT except they do not have a watchdog timer. Instead, they provide both RESET and RESET outputs. As with the MAX706, devices with R, S, and T suffixes have reset thresholds of 2.63V, 2.93V, and 3.08V, respectively. These devices are available in 8-pin SO, DIP, and MAX(R) packages and are fully specified over the operating temperature range. MAX Package, Small 8-Pin SO Precision Supply-Voltage Monitors 2.63V (MAX706P/R, MAX706AP/AR, and MAX708R) 2.93V (MAX706S, MAX706AS, and MAX708S) 3.08V (MAX706T, MAX706AT, and MAX708T) 200ms Reset Time Delay Debounced TTL/CMOS-Compatible Manual Reset Input 100A Quiescent Current WDI Disable Feature (MAX706AP/AR/AS/AT) Watchdog Timer: 1.6s Timeout Reset Output Signal: Active-High Only (MAX706P, MAX706AP) Active-Low Only (MAX706R/S/T, MAX706AR/AS/AT) Active-High and Active-Low (MAX708R/S/T) Voltage Monitor for Power-Fail or Low-Battery Warning 8-Pin Surface-Mount Package Guaranteed RESET Assertion to VCC = 1V
Features
MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
Ordering Information
PART MAX706PCPA MAX706PCSA MAX706PCUA MAX706PEPA TEMP RANGE 0C to +70C 0C to +70C 0C to +70C -40C to +85C PINPACKAGE 8 PDIP 8 SO 8 MAX 8 PDIP PKG CODE P8-1 S8-2 U8-1 P8-1
SO, MAX, and PDIP packages are available in lead-free.
Ordering Information continued at end of data sheet. Pin Configurations appear at end of data sheet.
Applications
Battery-Powered Equipment Portable Instruments Computers Controllers Intelligent Instruments Critical P Power Monitoring
UNREGULATED DC
Typical Operating Circuits
MAX639 DC-DC CONVERTER +3V/+3.3V VCC MAX706R/S/T MAX706AR/AS/AT VCC PFI PUSHBUTTON SWITCH MR RESET WDI WDO PFO GND P RESET I/O LINE NMI INTERRUPT
MAX is a registered trademark of Maxim Integrated Products, Inc.
Typical Operating Circuits continued at end of data sheet. 1
________________________________________________________________ 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.
+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
ABSOLUTE MAXIMUM RATINGS
Terminal Voltage (with respect to GND) VCC ........................................................................-0.3V to +6V All Other Inputs (Note 1)..........................-0.3V to (VCC + 0.3V) Input Current VCC ..................................................................................20mA GND .................................................................................20mA Output Current (all outputs) ................................................20mA Continuous Power Dissipation (TA = +70C) 8-Pin CERDIP (derate 8mW/C above +70C)..............640mW 8-Pin PDIP (derate 9.1mW/C above +70C).............727.3mW 8-Pin SO (derate 5.9mW/C above +70C)................470.6mW 8-Pin MAX (derate 4.5mW/oC above +70C) ..............362mW Operating Temperature Range MAX70_C .............................................................0C to +70C MAX70_E ..........................................................-40C to +85C MAX70_M .......................................................-55C to +125C Junction Temperature ......................................................+150C Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C
Note 1: The input-voltage limits on PFI, WDI, and MR can be exceeded if the input current is less than 10mA.
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
(MAX70_P/R, MAX706AP/AR: VCC = 2.7V to 5.5V; MAX70_S, MAX706AS: VCC = 3.0V to 5.5V; MAX70_T, MAX706AT: VCC = 3.15V to 5.5V; TJ = TA = TMIN to TMAX, unless otherwise noted. Typical values are at TJ = TA = +25C.) (Note 2)
PARAMETER Supply Voltage Range SYMBOL VCC CONDITIONS MAX70_C MAX70_E/M MAX706_C VCC < 3.6V Supply Current ISUPPLY VCC < 5.5V MAX706_E/M MAX708_C MAX708_E/M MAX706_C MAX706_E/M MAX708_C MAX708_E/M MAX70_P/R/, MAX706AP/AR Reset Threshold (Note 3) (VCC Falling) Reset Threshold Hysteresis (Note 3) Reset Pulse Width (Note 3) RESET OUTPUT VOH VOL Output-Voltage High (MAX70_R/S/T) (MAX706AR/AS/AT) VOH VOL VOL VRST(MAX) < VCC < 3.6V ISOURCE = 500A VRST(MAX) < VCC < 3.6V ISINK = 1.2mA 4.5V < VCC < 5.5V 4.5V < VCC < 5.5V IRSOURCE = 800A ISINK = 3.2mA VCC 1.5 0.4 0.3 0.3 0.8 x VCC 0.3 V VRST MAX70_S, MAX706AS MAX70_T, MAX706AT VHYS MAX70_P/R/, MAX706AP/AR VCC = 3.0V tRST MAX70_S, MAX706AS, VCC = 3.3V VCC = 5V 140 140 2.55 2.85 3.00 MIN 1.0 1.2 90 90 50 50 135 135 65 65 2.63 2.93 3.08 20 200 200 200 280 280 ms TYP MAX 5.5 5.5 200 300 200 300 350 500 350 500 2.70 3.00 3.15 mV V A UNITS V
MAX70_C VCC = 1.0V, ISINK = 50A MAX70_E/M: VCC = 1.2V, ISINK = 100A
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+3V Voltage Monitoring, Low-Cost P Supervisory Circuits
ELECTRICAL CHARACTERISTICS (continued)
(MAX70_P/R, MAX706AP/AR: VCC = 2.7V to 5.5V; MAX70_S, MAX706AS: VCC = 3.0V to 5.5V; MAX70_T, MAX706AT: VCC = 3.15V to 5.5V; TJ = TA = TMIN to TMAX, unless otherwise noted. Typical values are at TJ = TA = +25C.) (Note 2)
PARAMETER SYMBOL VOH Output-Voltage High (MAX706P) (MAX706AP) VOL VOH VOL VOH Output-Voltage High (MAX708_) VOL VOH VOL WATCHDOG INPUT Watchdog Timeout Period tWD MAX706P/R, MAX706AP/AR, VCC = 3.0V MAX706S/T, MAX706AS/AT, VCC = 3.3V VRST(MAX) < VCC VIL = 0.4V < 3.6V 4.5V < VCC < VIH = 0.8V x VCC 5.5V VRST(MAX) < VCC < 3.6V VRST(MAX) < VCC < 3.6V VCC = 5.0V VCC = 5.0V WDI = 0V or VCC MAX706_ MAX706A_ 3.5 -1.0 -5 +0.02 +1.0 +5 A 1.00 1.00 100 ns 50 0.6 0.7 x VCC 0.8 V 1.60 1.60 2.25 2.25 s CONDITIONS VRST(MAX) < VCC < 3.6V ISOURCE = 215A VRST(MAX) < VCC < 3.6V ISINK = 1.2mA 4.5 < VCC < 5.5V 4.5V < VCC < 5.5V ISOURCE = 800A ISINK = 3.2mA VCC 1.5 0.4 0.3 VCC 1.5 0.4 V MIN VCC 0.6 0.3 V TYP MAX UNITS
MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
VRST(MAX) < VCC < 3.6V ISOURCE = 500A 0.8 x VCC VRST(MAX) < VCC < 3.6V ISINK = 500A 4.5V < VCC < 5.5V 4.5V < VCC < 5.5V ISOURCE = 800A ISINK = 1.2mA
WDI Pulse Width (MAX706_, MAX706A_)
tWP VIL
Watchdog Input Threshold (MAX706_, MAX706A_)
VIH VIL VIH
WDI Input Current
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+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
ELECTRICAL CHARACTERISTICS (continued)
(MAX70_P/R, MAX706AP/AR: VCC = 2.7V to 5.5V; MAX70_S, MAX706AS: VCC = 3.0V to 5.5V; MAX70_T, MAX706AT: VCC = 3.15V to 5.5V; TJ = TA = TMIN to TMAX, unless otherwise noted. Typical values are at TJ = TA = +25C.) (Note 2)
PARAMETER WATCHDOG OUTPUT VOH WDO Output Voltage (MAX706_, MAX706A_) VOL VOH VOL MANUAL RESET INPUT VRST(MAX) < VCC < 3.6V 4.5V < VCC < 5.5V MR Pulse Width tMR VIL MR Input Threshold VIH VIL VIH MR to Reset Output Delay POWER-FAILURE COMPARATOR (MAX70_P/R, MAX706AP/AR) PFI falling VCC = 3.0V (MAX70_S/T, MAX706AS/AT) PFI falling, VCC = 3.3V PFI Input Current VOH PFO Output Voltage VOL VOH VOL VRST(MAX) < VCC < 3.6V ISOURCE = 500A VRST(MAX) < VCC < 3.6V ISINK = 1.2mA 4.5V < VCC < 5.5V 4.5V < VCC < 5.5V ISOURCE = 800A ISINK = 3.2mA VCC 1.5 0.4 1.20 1.20 -25 0.8 x VCC 0.3 V 1.25 1.25 +0.01 1.30 V 1.30 +25 nA tMD VRST(MAX) < VCC < 3.6V 4.5V < VCC < 5.5V VRST(MAX) < VCC < 3.6V VRST(MAX) < VCC < 3.6V 4.5V < VCC < 5.5V 4.5V < VCC < 5.5V VRST(MAX) < VCC < 3.6V 4.5V < VCC < 5.5V 2.0 750 250 ns 0.7 x VCC 0.8 25 100 500 150 0.6 V 70 250 250 A 600 ns VRST(MAX) < VCC < 3.6V ISOURCE = 500A VRST(MAX) < VCC < 3.6V ISINK = 500A 4.5V < VCC < 5.5V 4.5V < VCC < 5.5V ISOURCE = 800A ISINK = 1.2mA VCC 1.5 0.4 0.8 x VCC 0.3 V SYMBOL CONDITIONS MIN TYP MAX UNITS
MR Pullup Current
MR = 0
PFI Input Threshold
Note 2: All devices 100% production tested at TA = +85C. Limits over temperature are guaranteed by design. Note 3: Applies to both RESET in the MAX70_R/S/T and MAX706AR/AS/AT, and RESET in the MAX706P/MAX706AP.
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+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
Typical Operating Characteristics
(TA = +25C, unless otherwise noted.)
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+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
Pin Description
PIN MAX706P MAX706AP SO/DIP MAX MAX706R/S/T, MAX706AR/AS/AT SO/DIP MAX MAX708R/S/T SO/DIP MAX Active-Low, Manual-Reset Input. Pull MR below 0.6V to trigger a reset pulse. MR is TTL/CMOS compatible when VCC = 5V and can be shorted to GND with a switch. MR is internally connected to a 70A source current. Connect to VCC or leave unconnected. Supply Voltage Input Ground Adjustable Power-Fail Comparator Input. Connect PFI to a resistive divider to set the desired PFI threshold. When PFI is less than 1.25V, PFO goes low and sinks current; otherwise, PFO remains high. Connect PFI to GND if not used. Active-Low, Power-Fail Comparator Output. PFO asserts when PFI is below the internal 1.25V threshold. PFO deasserts when PFI is above the internal 1.25V threshold. Leave PFO unconnected if not used. Watchdog Input. A falling or rising transition must occur at WDI within 1.6s to prevent WDO from asserting (see Figure 4). The internal watchdog timer is reset to zero when reset is asserted or when transition occurs at WDI. The watchdog function for the MAX706P/R/S/T can not be disabled. The watchdog timer for the MAX706AP/AR/AS/AT disables when WDI input is left open or connected to a tri-state output in its high-impedance state with a leakage current of less than 600nA. NAME FUNCTION
1
3
1
3
1
3
MR
2 3
4 5
2 3
4 5
2 3
4 5
VCC GND
4
6
4
6
4
6
PFI
5
7
5
7
5
7
PFO
6
8
6
8
--
--
WDI
7
1
--
--
8
2
Active-High Reset Output. Reset remains high when VCC is RESET below the reset threshold or MR is held low. It remains low for 200ms after the reset conditions end (Figure 3). Active-Low Watchdog Output. WDO goes low when a transition does not occur at WDI within 1.6s and remains low until a transition occurs at WDI (indicating the watchdog interrupt has been serviced). WDO also goes low when VCC falls below the reset threshold; however, unlike the reset output signal, WDO goes high as soon as VCC rises above the reset threshold.
8
2
8
2
--
--
WDO
-- --
-- --
7 --
1 --
7 6
1 8
Active-Low Reset Output. RESET remains low when VCC is RESET below the reset threshold or MR is held low. It remains low for 200ms after the reset conditions end (Figure 3). N.C. No Connection. Not internally connected.
6
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+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
WDI
6
WATCHDOG TRANSITION DETECTOR VCC 70A
WATCHDOG TIMER
8
WDO
VCC 70A MR 1 2 RESET GENERATOR
8
RESET
TIMEBASE FOR RESET AND WATCHDOG 7
MR
1 2 RESET GENERATOR VCC RESET (RESET)
7
RESET
VCC
PFI
4
2.63V MAX706P/R 2.93V MAX706S MAX706P/R/S/T 3.08V MAX706T MAX706AP/AR/AS/AT 5 PFO
PFI
4
2.63V MAX708R 2.93V MAX708S 3.08V MAX708T
MAX708R/S/T
5 PFO
1.25V
1.25V 3 GND ( ) ARE FOR MAX706P/AP. 3 GND
Figure 1. MAX706_ Functional Diagram
Figure 2. MAX708_ Functional Diagram
RESET and RESET Outputs
A microprocessor's (P's) reset input starts in a known state. When the P is in an unknown state, it should be held in reset. The MAX706P/R/S/T and the MAX706AP/ AR/AS/AT assert reset when V CC is low, preventing code execution errors during power-up, power-down, or brownout conditions. On power-up once VCC reaches 1V, RESET is guaranteed to be logic-low and RESET is guaranteed to be logic-high. As VCC rises, RESET and RESET remain asserted. Once VCC exceeds the reset threshold, the internal timer causes RESET and RESET to be deasserted after a time equal to the reset pulse width, which is typically 200ms (Figure 3). If a power-fail or brownout condition occurs (i.e., VCC drops below the reset threshold), RESET and RESET are asserted. As long as VCC remains below the reset threshold, the internal timer is continually reset, causing the RESET and RESET outputs to remain asserted. Thus, a brownout condition that interrupts a previously initiated reset pulse causes an additional 200ms delay from the time the latest interruption occurred. On power-down once VCC drops below the reset threshold,
RESET and RESET are guaranteed to be asserted for VCC 1V. The MAX706P/MAX706AP provide a RESET signal, and the MAX706R/S/T and MAX706AR/AS/AT provide a RESET signal. The MAX708R/S/T provide both RESET and RESET.
Watchdog Timer
The MAX706P/R/S/T and the MAX706AP/AR/AS/AT watchdog circuit monitor the P's activity. If the P does not toggle the watchdog input (WDI) within 1.6s, the watchdog output (WDO) goes low (Figure 4). If the reset signal is asserted, the watchdog timer will be reset to zero and disabled. As soon as reset is released, the timer starts counting. WDI can detect pulses as narrow as 100ns with a 2.7V supply and 50ns with a 4.5V supply. The watchdog timer for the MAX706P/R/S/T cannot be disabled. The watchdog timer for the MAX706AP/AR/AS/AT operates similarly to the MAX706P/R/S/T. However, the watchdog timer for the MAX706AP/AR/AS/AT disables when the WDI input is left open or connected to a tri-state output in its highimpedance state and with a leakage current of less than 600nA. The watchdog timer can be disabled anytime, provided WDO is not asserted.
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+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
+3.3V VCC +1V VRST VRST tRST RESET 0V +3.3V RESET 0V +3.3V MR* 0V tRST
+12V
+3V/+3.3V RESET (RESET)
1M 1%
VCC
TO P
MAX706_ MAX708R/S/T
MR PFI GND PFO
130k 1%
tMD tMR *NOTE: MR EXTERNALLY DRIVEN LOW. WDO TIMING SHOWN FOR MAX706P/R/S/T.
+3.3V WDO* 0V
PARAMETER
MIN
TYP 10.87
MAX 11.50
UNIT V
+12V RESET 10.24 THRESHOLD AT +25C ( ) ARE FOR MAX706P/AP
Figure 3. RESET, RESET, MR, and WDO Timing
tWP tWD +3V/+3.3V WDI 0V +3V/+3.3V WDO 0V +3V/+3.3V RESET 0V RESET EXTERNALLY TRIGGERED BY MR tRST
tWD
tWD
Figure 5. Monitoring Both +3V/+3.3V and +12V
MAX706R/S/T MAX708R/S/T MAX706AR/AS/AT RESET R1
Figure 4. MAX706AP/AR/AS/AT Watchdog Timing
WDO can be connected to the nonmaskable interrupt (NMI) input of a P. When VCC drops below the reset threshold, WDO immediately goes low, even if the watchdog timer has not timed out (Figure 3). Normally, this would trigger an NMI, but since reset is asserted simultaneously, the NMI is overridden. The WDO should not be connected to RESET directly. Instead, connect WDO to MR to generate a reset pulse when it times out.
Figure 6. RESET Valid to GND Circuit
input pulse width is 500ns when VCC = +3V and 150ns when VCC = +5V. Leave MR unconnected or connect to VCC when not used.
Power-Fail Comparator
The power-fail comparator can be used for various purposes because its output and noninverting input are not internally connected. The inverting input is internally connected to a 1.25V reference. The power-fail comparator has 10mV of hysteresis, which prevents repeated triggering of the power-fail output (PFO).
Manual Reset
The manual reset (MR) input allows RESET and RESET to be activated by a pushbutton switch. The switch is effectively debounced by the 140ms minimum reset pulse width. MR can be driven by an external logic line since it is TTL/CMOS compatible. The minimum MR
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+3V Voltage Monitoring, Low-Cost P Supervisory Circuits
To build an early-warning power-failure circuit, use the power-fail comparator input (PFI) to monitor the unregulated DC supply voltage (see the Typical Operating Circuits). Connect the PFI to a resistive-divider network such that the voltage at PFI falls below 1.25V just before the regulator drops out. Use PFO to interrupt the P so it can prepare for an orderly power-down. Regulated and unregulated voltages can be monitored by simply adjusting the PFI resistive-divider network values to the appropriate ratio. In addition, the reset signal can be asserted at voltages other that VCC reset threshold, as shown in Figure 5. Connect PFO to MR to initiate a reset pulse when the 12V supply drops below a user-specified threshold (11V in this example) or when VCC falls below the reset threshold.
MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
VIN R1
+3V/+3.3V VCC PFI C1* R3
MAX706_ MAX708R/S/T
R2 PFO GND TO P +3V/+3.3V PFO *OPTIONAL
Operation with +3V and +5V Supplies
The MAX706P/R/S/T, the MAX706AP/AR/AS/AT, and the MAX708R/S/T provide voltage monitoring at the reset threshold (2.63V to 3.08V) when powered from either +3V or +5V. These devices are ideal in portable-instrument applications where power can be supplied from either a +3V battery or an AC-DC wall adapter that generates +5V (a +5V supply allows a P or a microcontroller to run faster than a +3V supply). With a +3V supply, these ICs consume less power, but output drive capability is reduced, the MR to RESET delay time increases, and the MR minimum pulse width increases. The Electrical Characteristics table provides specifications for operation with both +3V and +5V supplies.
0V 0V VTRIP = 1.25 (R1 + R2) R2 VL VTRIP VH VIN
VH = 1.25 (1 + R3 + R2 R1) VL = 1.25 + R1 1.25 - VCC - 1.25 R2 x R3 R2 R3
Figure 7. Adding Hysteresis to the Power-Fail Comparator
+3V/+3.3V R1 VCC PFI PFO
Ensuring a Valid RESET Output Down to VCC = 0V
When V CC falls below 1V, the MAX706R/S/T, MAX706AR/AS/AT, and MAX708R/S/T RESET output no longer sinks current; it becomes an open circuit. Highimpedance, CMOS logic inputs can drift to undetermined voltages if left as open circuit. If a pulldown resistor is added to the RESET pin , as shown in Figure 6, any stray charge or leakage current will flow to ground, holding RESET low. Resistor value R is not critical, but it should not load RESET and should be small enough to pull RESET and the input it is driving to ground. 100k is suggested for R1.
MAX706_ MAX708R/S/T
R2 GND V-
+3V/+3.3V PFO 0V
VTRIP VCC - 1.25 1.25 - VTRIP = R1 R2 NOTE: VTRIP IS NEGATIVE.
V-
0V
Applications Information
Adding Hysteresis to the Power-Fail Comparator
Hysteresis adds a noise margin to the power-fail comparator and prevents repeated triggering of the PFO when VIN is near the power-fail comparator trip point. Figure 7 shows how to add hysteresis to the power-fail comparator. Select the ratio of R1 and R2 such that PFI
Figure 8. Monitoring a Negative Voltage
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+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
sees 1.25V when V IN falls to the desired trip point (VTRIP). Resistor R3 adds hysteresis. R3 will typically be an order of magnitude greater than R1 and R2. The current through R1 and R2 should be at least 1A to ensure that the 25nA (max) PFI input current does not shift the trip point significantly. R3 should be larger than 10k to prevent it from loading down the PFO pin. Capacitor C1 adds noise rejection.
Monitoring a Negative Voltage
The power-fail comparator can be used to monitor a negative supply voltage using the circuit of Figure 8. When the negative supply is valid, PFO is low. When the negative supply voltage drops, PFO goes high. This circuit's accuracy is affected by the PFI threshold tolerance, the VCC voltage, and resistors R1 and R2.
Bypassing VCC
For noisy systems, bypass VCC with a 0.1F capacitor to GND.
Ordering Information (continued)
PART MAX706PEUA MAX706PMJA MAX706RCPA MAX706RCSA MAX706RCUA MAX706REPA MAX706RESA MAX706REUA MAX706RMJA MAX706SCPA MAX706SCSA MAX706SCUA MAX706SEPA MAX706SESA MAX706SEUA MAX706SMJA MAX706TCPA MAX706TCSA MAX706TCUA MAX706TEPA MAX706TESA MAX706TEUA MAX706TMJA MAX706APEPA MAX706APESA MAX706APEUA MAX706AREPA MAX706ARESA MAX706AREUA MAX706ASEPA TEMP RANGE -40C to +85C 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -40C to +85C 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -40C to +85C 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C PINPACKAGE 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8MAX 8 Plastic Dip PKG CODE U8-1 J8-2 P8-1 S8-2 U8-1 P8-1 S8-2 U8-1 J8-2 P8-1 S8-2 U8-1 P8-1 S8-2 U8-1 J8-2 P8-1 S8-2 U8-1 P8-1 S8-2 U8-1 J8-2 P8-1 S8-2 U8-1 P8-1 S8-2 U8-1 P8-1 PART MAX706ASESA MAX706ASEUA MAX706ATEPA MAX706ATESA MAX706ATEUA MAX708RCPA MAX708RCSA MAX708RCUA MAX708REPA MAX708RESA MAX708REUA MAX708RMJA MAX708SCPA MAX708SCSA MAX708SCUA MAX708SEPA MAX708SESA MAX708SEUA MAX708SMJA MAX708TCPA MAX708TCSA MAX708TCUA MAX708TEPA MAX708TESA MAX708TEUA MAX708TMJA TEMP RANGE -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -40C to +85C -55C to +125C 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -40C to +85C -55C to +125C 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -40C to +85C -55C to +125C PINPACKAGE 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 CERDIP* 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 CERDIP* 8 Plastic Dip 8 SO 8 MAX 8 Plastic Dip 8 SO 8 MAX 8 CERDIP* PKG CODE S8-2 U8-1 P8-1 S8-2 U8-1 P8-1 S8-2 U8-1 P8-1 S8-2 U8-1 J8-2 P8-1 S8-2 U8-1 P8-1 S8-2 U8-1 J8-2 P8-1 S8-2 U8-1 P8-1 S8-2 U8-1 J8-2
-55C to +125C 8 CERDIP*
-55C to +125C 8 CERDIP*
-55C to +125C 8 CERDIP*
-55C to +125C 8 CERDIP*
SO, MAX, and PDIP packages are available in lead-free.
*Contact factory for availability and processing to MIL-STD-883. **Future product--contact factory for availability.
Chip Information
PROCESS: CMOS
10
______________________________________________________________________________________
+3V Voltage Monitoring, Low-Cost P Supervisory Circuits
Pin Configurations
TOP VIEW
MR VCC 1 2 8 7 WDO RESET WDI PFO VCC VCC PFI 1 2 8 7 WDO RESET WDI PFO MR GND MAX708R/S/T RESET RESET PFO INTERRUPT UNREGULATED DC MAX639
Typical Operating Circuits (continued)
DC-DC CONVERTER -3V/+3.3V P RESET
MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
GND 3 PFI 4
MAX706P MAX706AP
6 5
DIP/SO
MR VCC
PUSHBUTTON SWITCH
GND 3 MAX706AR/AS/AT 6 PFI 4 5
MAX706R/S/T
DIP/SO
MR VCC
1 2
8 7
RESET RESET N.C. PFO
GND 3 PFI 4
MAX708R/S/T
6 5
DIP/SO
(RESET) RESET WDO MR V CC
1 2 3 4
8
WDI PFO PFI GND
MAX706P/R/S/T MAX706AP/AR/ AS/AT
7 6 5
MAX
RESET RESET MR V CC
1 2 3 4
8 7
N.C. PFO PFI GND
MAX708R/S/T
6 5
MAX
( ) ARE FOR MAX706P/AP ONLY.
______________________________________________________________________________________
11
+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.)
CDIPS.EPS
12
______________________________________________________________________________________
+3V Voltage Monitoring, Low-Cost P Supervisory Circuits
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.)
8LUMAXD.EPS
MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
8
4X S
8
INCHES DIM A A1 A2 b c D e E H MIN 0.002 0.030 MAX 0.043 0.006 0.037
MILLIMETERS MAX MIN 0.05 0.75 1.10 0.15 0.95
O0.500.1 0.60.1
E
H
1
0.60.1
1
D
L
S
BOTTOM VIEW
0.014 0.010 0.007 0.005 0.120 0.116 0.0256 BSC 0.120 0.116 0.198 0.188 0.026 0.016 6 0 0.0207 BSC
0.25 0.36 0.13 0.18 2.95 3.05 0.65 BSC 2.95 3.05 4.78 5.03 0.41 0.66 0 6 0.5250 BSC
TOP VIEW
A2
A1
A
e
c b L
SIDE VIEW
FRONT VIEW
PROPRIETARY INFORMATION TITLE:
PACKAGE OUTLINE, 8L uMAX/uSOP
APPROVAL DOCUMENT CONTROL NO. REV.
21-0036
J
1 1
______________________________________________________________________________________
13
+3V Voltage Monitoring, Low-Cost P Supervisory Circuits MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.)
SOICN .EPS
INCHES DIM A A1 B C e E H L MAX MIN 0.053 0.069 0.004 0.010 0.014 0.019 0.007 0.010 0.050 BSC 0.150 0.157 0.228 0.244 0.050 0.016
MILLIMETERS MAX MIN 1.75 1.35 0.25 0.10 0.49 0.35 0.19 0.25 1.27 BSC 3.80 4.00 5.80 6.20 0.40 1.27
N
E
H
VARIATIONS:
1
INCHES
MILLIMETERS MIN 4.80 8.55 9.80 MAX 5.00 8.75 10.00 N MS012 8 AA 14 AB 16 AC
TOP VIEW
DIM D D D
MIN 0.189 0.337 0.386
MAX 0.197 0.344 0.394
D A e B A1 L C
0-8
FRONT VIEW
SIDE VIEW
PROPRIETARY INFORMATION TITLE:
PACKAGE OUTLINE, .150" SOIC
APPROVAL DOCUMENT CONTROL NO. REV.
21-0041
B
1 1
14
______________________________________________________________________________________
+3V Voltage Monitoring, Low-Cost P Supervisory Circuits
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.)
PDIPN.EPS
MAX706P/R/S/T, MAX706AP/AR/AS/AT, MAX708R/S/T
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 ____________________ 15 (c) 2006 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.

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