My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX815KESA+
- Part No.:
- MAX815KESA+
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Supervisors
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
MAX815KESA+.pdf
- Description:
- IC SUPERVISOR 1 CHANNEL 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:2,102
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MAX815KESA+ from Maxim Integrated is a high-accuracy, low-power microprocessor supervisory circuit with integrated watchdog timer, power-fail monitoring, and manual reset functionality. It features a 4.8V ±1% reset threshold, 200ms reset pulse width, 75µA max supply current, and guaranteed RESET validity down to VCC = 1V. It is used in portable medical instruments and battery-powered controllers requiring reliable brownout detection and fail-safe reset assertion.
For engineers reviewing the MAX815KESA+ datasheet, MAX815KESA+ pinout, MAX815KESA+ application, or MAX815KESA+ equivalent, this page delivers verified technical context, exact pin roles, real-world use cases, and validated alternative options for µP supervision in 5V systems with watchdog safety requirements.
Technical Context
The MAX815KESA+ implements a dedicated watchdog timer with 1.56s timeout, independent of the reset comparator, and triggers WDO low on timeout or VCC undervoltage. Its reset generator asserts active-low RESET for ≥200ms after VCC rises above 4.8V or MR release, with hysteresis-free propagation delay under 100ns.
Power-fail monitoring uses a 2.50V PFI threshold (K-suffix), driving open-drain PFO low when input falls below threshold; the LOW LINE output is absent (exclusive to MAX814), and RESET IN functionality is excluded (exclusive to MAX816).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reset Threshold | 4.80V ±1% - ensures reliable reset assertion in 5V ±4% systems meeting worst-case IC operating voltage (VICMIN) margin |
| Watchdog Timeout | 1.56s - provides sufficient window for firmware recovery while preventing indefinite hang states in embedded µP applications |
| Supply Current | 75µA max - enables multi-year operation in coin-cell–powered portable equipment without compromising supervision integrity |
| RESET Pulse Width | 200ms min - guarantees full µP initialization cycle completion before release, even during marginal VCC rise rates |
| VCC Operating Range | 4.85V to 5.5V - supports stable operation across full 5V rail tolerance band while maintaining ±1% threshold accuracy |
| PFI Threshold | 2.50V - allows early warning detection of +12V or +5V supply degradation via external resistive divider |
| RESET Validity | Down to VCC = 1V - maintains defined logic state through deep brownout, eliminating floating reset inputs during critical shutdown |
Pinout & Package
MAX815KESA+ is housed in an 8-pin SOIC package (SO) with gull-wing leads, 1.27mm pitch, and JEDEC MS-012AC compliance. Thermal resistance θJA = 160°C/W; maximum power dissipation at +25°C is 471mW.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 MR | Manual Reset Input | Active-low CMOS-compatible input with 150µA internal pullup; triggers reset when pulled <1.10V; debounced by 200ms internal timer |
| 2 VCC | Positive Power Supply | Primary supply input; reset asserted when VCC <4.80V; valid operation requires 4.85V–5.5V range per datasheet |
| 3 GND | Ground Reference | System ground return path for all internal comparators, timers, and outputs; must be low-impedance connection |
| 4 PFI | Power-Fail Input | Analog input referenced to 2.50V; monitors external voltage dividers for early undervoltage warning prior to reset threshold crossing |
| 5 PFO | Power-Fail Output | Open-drain output sinking ≥1.2mA at 0.4V; asserts low when PFI <2.50V; used to trigger µP NMI or initiate controlled shutdown |
| 6 WDI | Watchdog Input | CMOS-level input toggled by firmware; timeout occurs if static >1.56s; transitions reset internal watchdog counter |
| 7 RESET | Reset Output | Active-low push-pull output; sinks ≥3.2mA at 0.4V; remains low for ≥200ms after VCC rise or MR release |
| 8 WDO | Watchdog Output | Active-low open-drain output; goes low on watchdog timeout or VCC <4.80V; no minimum pulse width; fast edge response |
Key Features
| Feature | Design Value |
|---|---|
| ±1% Worst-Case Reset Threshold Accuracy | Eliminates manual trimming and ensures deterministic reset behavior across temperature (-40°C to +85°C) and supply variation |
| Independent Watchdog with 1.56s Timeout | Provides hardware-enforced firmware liveness check without interfering with reset timing or power-fail monitoring paths |
| 75µA Max Supply Current | Enables integration into energy-constrained portable designs without degrading battery life or requiring auxiliary power management |
| Guaranteed RESET Validity to VCC = 1V | Prevents undefined µP state during deep brownout by maintaining known logic level until supply collapses completely |
| Power-Supply Glitch Immunity | Rejects transients ≤30µs at 100mV overdrive, avoiding spurious resets in electrically noisy industrial or automotive environments |
Applications
| Medical Patient Monitor | Industrial PLC Controller |
|---|---|
Use Scenario: Continuous vital-sign acquisition in battery-backed portable ECG units where unexpected µP lockup must trigger immediate safe shutdown and data preservation. IC Role / Device Role / Timing Role: Supervisory watchdog asserts WDO to NMI interrupt upon firmware stall; simultaneous RESET ensures full µP reboot before next measurement cycle. Use Value: Prevents corrupted waveform storage and false alarm generation by enforcing deterministic recovery within 1.56s of software hang. |
Use Scenario: Real-time I/O control in factory-floor programmable logic controllers powered from unregulated 24VDC rails subject to motor-switching transients. IC Role / Device Role / Timing Role: PFI monitors regulated 5V supply via resistor divider; PFO triggers µP interrupt to log fault before VCC drops below 4.8V reset threshold. Use Value: Enables predictive maintenance logging and graceful I/O freeze instead of abrupt system crash during supply sag. |
| Handheld Diagnostic Tool | Set-Top Box Power Management |
Use Scenario: Field-deployable diagnostic scanner using Li-ion battery with aging-induced voltage droop during high-current RF transmission bursts. IC Role / Device Role / Timing Role: MR pin connected to front-panel reset switch; RESET output holds µP in known state during hot-swap battery replacement. Use Value: Eliminates need for external RC debounce and guarantees 200ms minimum reset hold time regardless of switch bounce duration. |
Use Scenario: Consumer set-top box requiring zero-downtime firmware updates and protection against power glitches during HDMI handshake sequences. IC Role / Device Role / Timing Role: WDI driven by bootloader code; WDO tied to MR to force hardware reset if update fails to toggle watchdog within 1.56s window. Use Value: Ensures automatic fallback to factory image without user intervention when OTA update stalls mid-process. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar microprocessor supervisory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX814KESA+ | Lacks watchdog timer; includes LOW LINE output and active-high RESET pin (pin 8) | Suitable for systems needing dual-reset signaling but no firmware liveness monitoring | Select when watchdog functionality is unnecessary and dual-reset polarity simplifies µP interface |
| TPS3808G33DBVR | 3.3V fixed reset threshold; no PFI/PFO; 350ms reset timeout; 2.5µA quiescent current | Optimized for ultra-low-power 3.3V microcontrollers; lacks power-fail warning capability | Choose for battery-critical 3.3V designs where early power-fail alert is not required |
Compared with MAX815KESA+, MAX814KESA+ provides identical reset accuracy and power-fail monitoring but omits watchdog safety, while TPS3808G33DBVR trades PFI flexibility and 5V compatibility for extreme low-power operation in 3.3V-only systems.
Availability
MAX815KESA+ is available at Aetrix Electronics and suitable for medical instrumentation, industrial controllers, portable diagnostics, and consumer set-top boxes requiring stable component supply with guaranteed long-term manufacturability.
Supply support for MAX815KESA+ 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, medical, and communications applications.
The MAX815KESA+ belongs to Maxim's µP supervisory product line, designed specifically for robust power-on reset, watchdog safety, and power-fail warning in 5V embedded systems where reliability under voltage stress is critical.
FAQ
What is the reset threshold voltage of the MAX815KESA+?
The MAX815KESA+ has a factory-trimmed reset threshold of 4.80V ±1%, optimized for 5V systems with ±4% supply tolerance. This value is fixed by the "K" suffix and confirmed in the Electrical Characteristics table for +5V parts. The threshold remains stable across -40°C to +85°C and ensures reset assertion before µP operating voltage (VICMIN) is violated. MAX815KESA+ does not support adjustable thresholds - that function is exclusive to the MAX816 series.
Does the MAX815KESA+ include a watchdog timer?
Yes, the MAX815KESA+ integrates a dedicated watchdog timer with a nominal timeout period of 1.56 seconds. It operates independently of the reset comparator and monitors the WDI pin: if WDI remains static (high or low) beyond 1.56s, WDO goes low. This feature is intrinsic to the MAX815 family and distinguishes it from the MAX814 (no watchdog) and MAX816 (adjustable reset, no watchdog). MAX815KESA+ uses this to enforce firmware liveness in safety-critical applications.
What is the function of the PFI and PFO pins on the MAX815KESA+?
On the MAX815KESA+, PFI is a dedicated analog input compared to a 2.50V internal reference; when voltage at PFI falls below 2.50V, the open-drain PFO pin pulls low (sinking ≥1.2mA). This enables early power-fail warning for supplies like +12V or +5V using an external resistor divider. Unlike RESET, PFO asserts *before* VCC crosses the 4.80V reset threshold - giving µP time to save data. MAX815KESA+ uses this for predictive shutdown in battery-powered and industrial systems.
Can the MAX815KESA+ operate with supply voltages below 4.85V?
No - the MAX815KESA+ is specified for VCC = 4.85V to 5.5V per its +5V parts electrical characteristics table. Operation below 4.85V violates the recommended operating conditions and may cause undefined behavior in the reset comparator, watchdog timer, or PFI comparator. While RESET remains valid down to VCC = 1V, functional operation (including accurate threshold detection and WDI sampling) requires the full 4.85V–5.5V range. For lower-voltage systems, consider the MAX815T variant (3.03V threshold) or MAX816 with adjustable input.
How is the manual reset (MR) pin used in the MAX815KESA+?
The MR pin on MAX815KESA+ is an active-low input with 150µA internal pullup to VCC. Pulling MR below 1.10V asserts RESET low immediately and holds it for ≥200ms after MR returns high - providing hardware-debounced reset initiation. It accepts CMOS/TTL logic levels and can be driven by switches, microcontrollers, or logic gates. MAX815KESA+ uses MR for field service reset, test-mode entry, or emergency recovery without requiring external components - a key advantage in space-constrained portable designs.
MAX815KESA+ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Simple Reset/Power-On Reset
- Number of Voltages Monitored:
- 1
- Voltage - Threshold:
- 4.8V
- Output:
- Push-Pull, Totem Pole
- Reset:
- Active Low
- Reset Timeout:
- 140ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
MAX815KESA+ FAQ
1.How can I place an order for MAX815KESA+ through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX815KESA+ 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 MAX815KESA+ reliable?
The price and inventory of MAX815KESA+ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX815KESA+ is usually 5 days.
3.What payment methods are accepted for MAX815KESA+?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX815KESA+ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX815KESA+?
MAX815KESA+ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX815KESA+ 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 MAX815KESA+?
For technical support, including MAX815KESA+ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX815KESA+ requirements.
6.How does Aetrix verify that MAX815KESA+ is sourced from the original manufacturer or authorized distributors?
All MAX815KESA+ 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 MAX815KESA+ meets industry standards.
7.What is the process for return or replacement of MAX815KESA+?
All MAX815KESA+ units undergo pre-shipment inspection (PSI). If there is an issue with MAX815KESA+, 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 MAX815KESA+ part is unused and in its original packaging.
Return procedure for MAX815KESA+:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX815KESA+ 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…
