My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX691AESE+
- Part No.:
- MAX691AESE+
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Supervisors
- Package:
- 16-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
MAX691AESE+.pdf
- Description:
- IC SUPERVISOR 1 CHANNEL 16SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:2,283
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MAX691AESE+ from Maxim Integrated is a microprocessor supervisory circuit providing power-on reset, watchdog timer, battery switchover, and chip-enable gating for 5V systems. It features a 4.65V typical reset threshold, 200ms reset timeout, 30μA operating supply current, and guaranteed RESET assertion down to VCC = 1V. It is used in industrial controllers and intelligent instruments requiring reliable brownout protection and nonvolatile memory write protection.
For engineers reviewing the MAX691AESE+ datasheet, MAX691AESE+ pinout, MAX691AESE+ application, or MAX691AESE+ equivalent, key selection criteria include reset threshold accuracy (±150mV), battery-backup mode operation with VCC down to 0V, CE signal propagation delay (≤10ns), and compatibility with MaxCap®/SuperCap™ backup capacitors.
Technical Context
The MAX691AESE+ integrates a precision voltage monitor, internal oscillator-based reset/watchdog timing, and bidirectional power-path control between VCC and VBATT. Its dual RESET/RESET outputs support both active-low and active-high μP reset inputs, while the open-drain RESET output remains valid at VCC as low as 1V.
Chip-enable gating uses a 75Ω transmission gate with ≤10ns propagation delay (50Ω source, 50pF load); the watchdog accepts three-level WDI input (high/low/floating) and disables automatically when unconnected or during reset assertion. Battery switchover activates when VCC falls below VBATT − 0.3V and remains asserted until VCC rises above VBATT + 0.3V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reset Threshold Voltage | 4.65V typical (MAX691A/MAX800L family); ensures reliable reset assertion before 5V system brownout. |
| Reset Timeout Period | 200ms typical on power-up; provides sufficient hold time for μP initialization and peripheral stabilization. |
| Supply Current (Operating) | 30μA typical; enables low-power monitoring in always-on embedded systems without significant battery drain. |
| VCC-to-VOUT On-Resistance | 0.8–1.4Ω (MAX691AESE+); supports up to 250mA continuous load with ≤200mV dropout at full current. |
| Watchdog Timeout (Long) | 1.6s nominal; detects μP lockup in real-time control loops without excessive false triggers. |
| Battery Switchover Hysteresis | 60mV; prevents oscillation during marginal VCC transitions near VBATT voltage. |
| CE Propagation Delay | 6–10ns (50Ω source, 50pF load); preserves timing integrity for high-speed memory access in μP systems. |
Pinout & Package
MAX691AESE+ is housed in a 16-pin narrow SO (Small Outline) package, RoHS-compliant and lead-free (indicated by '+' suffix), rated for −40°C to +85°C operation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 VBATT | Battery-Backup Input | Connects to backup capacitor/battery; enables seamless switchover when VCC fails; supports 2.0–5.5V range. |
| 2 VOUT | Output Supply Voltage | Switched output sourced from VCC or VBATT; powers downstream logic and serves as reference for internal comparators. |
| 3 VCC | Main Supply Input | 5V regulated input; monitored for reset generation and CE gating enable; tolerates 0–6V absolute max. |
| 4 GND | Ground Reference | 0V return path for all analog and digital functions; must be low-impedance for accurate voltage monitoring. |
| 5 BATT ON | Battery-On Status Output | Open-drain indicator (active-high) signaling VBATT is active; drives PNP base for >250mA external pass transistors. |
| 6 LOW LINE | Reset Comparator Buffer | Active-low buffered copy of reset comparator output; used for system status indication independent of RESET timing. |
| 7 OSC IN | External Oscillator Input | Accepts timing capacitor or external clock; sets watchdog/reset timeouts; internal 100nA current source enables RC timing. |
| 8 OSC SEL | Oscillator Select Control | Configures internal vs. external timing source; floating/high selects internal oscillator; low enables external timing. |
| 9 PFI | Power-Fail Input | Noninverting input to uncommitted comparator; threshold fixed at 1.25V ±25mV; used for early power-fail or low-battery warning. |
| 10 PFO | Power-Fail Output | Open-drain comparator output; asserts low when PFI < 1.25V; no effect on internal reset/watchdog functions. |
| 11 WDI | Watchdog Input | Three-level input (high/low/floating); transition resets watchdog timer; floating disables watchdog via internal 1.6V bias. |
| 12 CE OUT | Chip-Enable Output | Gated CE signal passed only when VCC > reset threshold; prevents RAM corruption during power failure. |
| 13 CE IN | Chip-Enable Input | High-impedance during reset; series 75Ω resistance in enabled mode; leakage ±1μA max over temperature. |
| 14 WDO | Watchdog Output | Active-low watchdog fault indicator; goes low on timeout and remains low until next WDI transition. |
| 15 RESET | Active-Low Reset Output | Open-drain output; sinks 3.2mA at 0.1V; guaranteed functional down to VCC = 1V; requires external pull-up. |
| 16 RESET | Active-High Reset Output | Open-drain inverse of RESET; high-impedance when inactive; used for μPs requiring active-high reset assertion. |
Key Features
| Feature | Design Value |
|---|---|
| Guaranteed RESET assertion to VCC = 1V | Enables robust reset signaling in deep brownout conditions where other supervisors fail, critical for data integrity in battery-backed RAM. |
| On-board CE signal gating with ≤10ns delay | Prevents spurious writes to CMOS RAM during power collapse without adding external logic or timing uncertainty. |
| MaxCap®/SuperCap™ compatible backup interface | Supports large-value backup capacitors (e.g., 0.47F) with controlled switchover, eliminating need for rechargeable batteries in many applications. |
| Dual RESET/RESET outputs | Simultaneously satisfies μPs requiring either active-low or active-high reset inputs-no level-shifting or external inverters needed. |
| Power-fail comparator with ±2% accuracy (MAX800L/M) | Provides precise early-warning detection for system shutdown or data save operations before main supply collapse. |
Applications
| Industrial PLC Controller | Medical Diagnostic Instrument |
|---|---|
Use Scenario: Programmable logic controller operating in factory environments with fluctuating 5V rail and requirement for deterministic boot sequence after power interruption. IC Role / Device Role / Timing Role: Supervisory IC providing power-on reset, watchdog supervision of firmware execution, and CE gating to protect configuration EEPROM during brownout. Use Value: Prevents corrupted I/O state or unsafe actuator positioning by ensuring μP starts only after stable VCC and enforcing periodic software sanity checks. |
Use Scenario: Portable ultrasound device with flash memory storage and battery backup, requiring data retention during AC power loss. IC Role / Device Role / Timing Role: Dual-role supervisor: generates clean reset for ARM Cortex-M core and manages seamless switchover to supercapacitor to maintain SRAM and real-time clock. Use Value: Guarantees uninterrupted operation of time-critical subsystems (e.g., ADC sampling, display refresh) for ≥200ms after main power loss. |
| Telecom Base Station Management Card | Energy Meter with Tamper Detection |
Use Scenario: Remote management card in LTE base station handling SNMP polling, firmware updates, and alarm reporting under wide ambient temperature range. IC Role / Device Role / Timing Role: High-reliability supervisor monitoring 5V management rail, asserting RESET on undervoltage, and enabling watchdog-triggered recovery from hung communication stacks. Use Value: Reduces field service calls by autonomously recovering from transient software faults without manual reboot, meeting carrier-grade uptime SLAs. |
Use Scenario: ANSI C12.20-certified smart meter with secure crypto module and nonvolatile event logging, deployed in outdoor substations. IC Role / Device Role / Timing Role: Power integrity guardian: monitors VCC for tamper-induced voltage glitching, asserts RESET to halt crypto operations, and triggers secure erase via PFO-linked circuitry. Use Value: Meets anti-tampering requirements by detecting sub-100ms supply anomalies and initiating irreversible security actions before sensitive keys are exposed. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar microprocessor supervisory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX691ACSE+ | Same functionality but rated for 0°C to +70°C; lower temperature grade; identical pinout and electrical specs. | Suitable for commercial-grade equipment with controlled ambient; not qualified for extended industrial temperature range. | Select MAX691ACSE+ only if operating environment stays within 0–70°C and cost sensitivity outweighs long-term reliability margin. |
| TPS3808G33DBVR | Single-supply 3.3V supervisor; no battery switchover, no CE gating, no dual RESET outputs; 3.08V reset threshold. | Lacks backup power management and memory write protection features; intended for simpler 3.3V-only systems. | Choose TPS3808G33DBVR only for cost-optimized 3.3V designs without battery backup or RAM write protection needs. |
Compared with MAX691ACSE+, the MAX691AESE+ adds −40°C to +85°C operation for harsh environments; compared with TPS3808G33DBVR, it delivers integrated battery switchover, CE gating, and dual reset outputs-enabling single-chip supervision of complex 5V industrial systems.
Availability
MAX691AESE+ is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic instruments, telecom management cards, and energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for MAX691AESE+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.
The MAX691A family was designed specifically for robust μP supervision in mission-critical 5V systems-integrating reset, watchdog, battery switchover, and memory protection in a single 16-pin package.
FAQ
What is the operating temperature range for the MAX691AESE+?
The MAX691AESE+ is specified for −40°C to +85°C operation, making it suitable for industrial and outdoor applications where ambient temperatures exceed commercial-grade limits. This extended range is confirmed in the Ordering Information table and applies to all electrical parameters unless otherwise noted in the Electrical Characteristics section.
Does the MAX691AESE+ support battery backup with supercapacitors?
Yes, the MAX691AESE+ explicitly supports MaxCap® and SuperCap™ backup capacitors per its Features list and Typical Operating Circuit. Its VBATT input handles up to 5.5V and its switchover comparator activates when VCC falls below VBATT − 0.3V, enabling seamless transition to capacitor-supplied power without external circuitry.
How does the watchdog function behave when WDI is left unconnected?
When WDI is unconnected, an internal voltage divider biases it to ~1.6V, which disables the watchdog timer per the Detailed Description. The WDO output remains high, and no reset pulses are generated-ensuring safe default behavior without requiring external pull-up/down resistors.
Can the MAX691AESE+ generate both active-high and active-low reset signals simultaneously?
Yes, the MAX691AESE+ provides two independent reset outputs: pin 15 (RESET, active-low open-drain) and pin 16 (RESET, active-high open-drain). Both are asserted concurrently during power-up or watchdog timeout, allowing direct interface to μPs requiring either polarity without additional logic.
What is the maximum continuous current supported on the VOUT pin of the MAX691AESE+?
The MAX691AESE+ supports up to 250mA continuous current on VOUT in normal operating mode (VCC-powered), with VCC-to-VOUT on-resistance of 0.8–1.4Ω resulting in ≤200mV dropout at full load. In battery-backup mode, VBATT-to-VOUT on-resistance rises to 15–30Ω, limiting practical current to ≤25mA.
MAX691AESE+ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 16-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Battery Backup Circuit
- Number of Voltages Monitored:
- 1
- Voltage - Threshold:
- 4.65V
- Output:
- Push-Pull, Push-Pull
- Reset:
- Active High/Active Low
- Reset Timeout:
- 140ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-SOIC
MAX691AESE+ FAQ
1.How can I place an order for MAX691AESE+ through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX691AESE+ on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MAX691AESE+ reliable?
The price and inventory of MAX691AESE+ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX691AESE+ is usually 5 days.
3.What payment methods are accepted for MAX691AESE+?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX691AESE+ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX691AESE+?
MAX691AESE+ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX691AESE+ order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MAX691AESE+?
For technical support, including MAX691AESE+ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX691AESE+ requirements.
6.How does Aetrix verify that MAX691AESE+ is sourced from the original manufacturer or authorized distributors?
All MAX691AESE+ products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MAX691AESE+ meets industry standards.
7.What is the process for return or replacement of MAX691AESE+?
All MAX691AESE+ units undergo pre-shipment inspection (PSI). If there is an issue with MAX691AESE+, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MAX691AESE+ part is unused and in its original packaging.
Return procedure for MAX691AESE+:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX691AESE+ Tags
-
MIC826SYMT-TR
Microchip Technology
-
APX803S-31SA-7
Diodes Incorporated
-
APX803L20-29SA-7
Diodes Incorporated
-
TPS3828-33DBVR
Texas Instruments
-
V6340RSP3B+
EM Microelectronic
-
EM6325CXSP5B-2.9+
EM Microelectronic
-
MCP120T-300I/TT
Microchip Technology
-
MCP130T-315I/TT
Microchip Technology
-
MCP120T-475I/TT
Microchip Technology
-
MCP111T-300E/TT
Microchip Technology
-
MCP120T-315I/TT
Microchip Technology
-
MCP809T-315I/TT
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
