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Analog Devices Inc./Maxim Integrated MAX6865UK18D3S+T
- Part No.:
- MAX6865UK18D3S+T
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Supervisors
- Package:
- SC-74A, SOT-753
- Datasheet:
-
MAX6865UK18D3S+T.pdf
- Description:
- IC SUPERVISOR 1 CHANNEL SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,735
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Product details
Overview
MAX6865UK18D3S+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, factory-trimmed 1.8V reset threshold (±2.5%), 300ms minimum reset timeout, and integrated watchdog timer with 3.3s typical timeout. It monitors VCC, responds to manual reset (MR), and asserts active-high push-pull RESET during brownout or watchdog expiration - used in battery-powered glucose monitors and portable medical devices.
For engineers reviewing the MAX6865UK18D3S+T datasheet, MAX6865UK18D3S+T pinout, MAX6865UK18D3S+T application, or MAX6865UK18D3S+T equivalent, key selection criteria include its 1.8V reset threshold accuracy, guaranteed RESET validity down to VCC = +1.1V, 3.3s watchdog timeout option (S-suffix), and compatibility with low-voltage µP systems requiring <200nA quiescent current.
Technical Context
The MAX6865UK18D3S+T implements a precision bandgap-based voltage monitor with 2.5% threshold tolerance over -40°C to +85°C, coupled with a digital watchdog timer that clears on any WDI edge and expires if WDI remains static beyond 3.3s (typ). Its internal MR pullup (10kΩ) enables direct switch interface without external components.
RESET assertion is synchronized to VCC crossing the 1.8V threshold, with a fixed 300ms (min) timeout after VCC recovery and MR deassertion. The active-high push-pull output drives directly to VCC, eliminating need for external pullups and supporting logic-level compatibility with 1.8V–5.5V µPs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reset Threshold | 1.800V ±2.5% - factory-trimmed for stable brownout detection at 1.8V rail |
| Supply Current | 170nA (typ) at VCC = 1.8V - enables multi-year operation on coin-cell batteries |
| Reset Timeout | 300ms (min) - ensures µP completes power-up initialization before release |
| Watchdog Timeout | 3.3s (typ), S-suffix - detects firmware hangs in low-duty-cycle embedded applications |
| VCC Operating Range | 1.2V to 5.5V - supports single-supply operation across 1.8V, 2.5V, 3.3V, and 5V systems |
| RESET Validity | Guaranteed to VCC = +1.1V - maintains valid reset signal during deep brownout |
| MR Input Logic | Active-low, internally pulled up to VCC (10kΩ) - accepts CMOS or open-drain drive |
Pinout & Package
Package: 5-pin SOT23-5, lead-free (RoHS-compliant), footprint compatible with industry-standard 5-pin SOT23 layouts.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | RESET | Active-high push-pull reset output - drives high during fault; no external pullup required |
| 2 | GND | Ground reference - must be connected to system ground plane for noise immunity |
| 3 | MR | Active-low manual reset input - initiates reset when pulled low; internally pulled up to VCC |
| 4 | WDI | Watchdog input - edge-sensitive; clears internal timer on rising/falling transitions |
| 5 | VCC | Supply voltage input - monitored rail; bypass with 0.1µF capacitor to GND per layout best practice |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low ICC | 170nA typical supply current enables >10-year battery life in coin-cell–powered devices |
| Immunity to VCC transients | Rejects ≤40µs glitches at 100mV overdrive - prevents false resets in noisy power environments |
| No external components | Integrated MR pullup (10kΩ), precision voltage reference, and watchdog timer eliminate BOM parts |
| Valid RESET at low VCC | RESET remains functional down to VCC = +1.1V - critical for graceful shutdown in brownout conditions |
| Watchdog edge sensitivity | Detects WDI pulses as short as 150ns - supports high-frequency software heartbeat signaling |
Applications
| Glucose Monitors | Patient Monitoring Devices |
|---|---|
Use Scenario: Portable handheld glucose meters operating from CR2032 coin cell with intermittent sensor sampling. IC Role / Device Role / Timing Role: Supervisory IC monitoring 1.8V µP supply and asserting RESET on brownout or firmware hang via WDI. Use Value: 170nA ICC extends battery life beyond 3 years; 300ms reset timeout ensures reliable µP boot after wake-from-sleep. |
Use Scenario: Battery-backed ECG/SpO₂ modules requiring fail-safe restart after power interruption. IC Role / Device Role / Timing Role: Active-high RESET generator triggered by VCC drop below 1.8V or missed WDI toggle within 3.3s. Use Value: Guaranteed RESET validity to VCC = +1.1V prevents undefined µP state during gradual battery depletion. |
| Smart Wearables | Industrial Sensor Nodes |
Use Scenario: Ultra-low-power fitness trackers using 1.8V ARM Cortex-M0+ MCU with periodic BLE transmission. IC Role / Device Role / Timing Role: Watchdog supervisor ensuring firmware execution integrity between sensor reads and radio bursts. Use Value: 3.3s watchdog timeout aligns with typical task loop duration; SOT23-5 footprint minimizes PCB area. |
Use Scenario: Remote LoRaWAN temperature/humidity sensors powered by primary lithium cells. IC Role / Device Role / Timing Role: Voltage monitor and watchdog enforcing safe boot and runtime supervision under wide temperature (-40°C to +85°C). Use Value: Factory-trimmed 1.8V threshold eliminates calibration; 2.5% tolerance ensures consistent trip point across temperature. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar microprocessor supervisory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS3836K33DBVR | Fixed 3.3V reset threshold; no watchdog; 200ms timeout; 1.6µA ICC | Lacks watchdog functionality; higher supply current limits battery life | Select only if system requires 3.3V supervision without watchdog and can tolerate higher ICC |
| STM6315SW13F | 1.3V reset threshold; 200ms timeout; no watchdog; 1.2µA ICC; push-pull active-low RESET | Lower threshold incompatible with 1.8V systems; active-low output requires level-shifting for some µPs | Use only for 1.3V rail monitoring; not suitable as direct replacement for MAX6865UK18D3S+T's 1.8V/WDI function set |
Compared with TPS3836K33DBVR and STM6315SW13F, the MAX6865UK18D3S+T uniquely combines 1.8V precision reset, 3.3s watchdog, and 170nA ICC in a single SOT23-5 package - making it irreplaceable for long-life, low-voltage medical and wearable applications requiring both voltage and software supervision.
Availability
MAX6865UK18D3S+T is available at Aetrix Electronics and suitable for portable medical devices, battery-powered wearables, and industrial sensor nodes requiring stable component supply with guaranteed long-term availability and RoHS-compliant packaging.
Supply support for MAX6865UK18D3S+T 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) designs precision analog and mixed-signal ICs for power management, sensing, and interface applications in demanding industrial, medical, and communications systems.
The MAX6865UK18D3S+T belongs to the MAX68xx nanopower supervisory family, engineered specifically for ultra-low-power battery-operated systems requiring simultaneous voltage monitoring, manual reset, and watchdog timer functionality in minimal footprint.
FAQ
What is the exact reset threshold voltage of the MAX6865UK18D3S+T?
The MAX6865UK18D3S+T has a factory-trimmed reset threshold of 1.800V with ±2.5% tolerance over -40°C to +85°C, confirmed in Table 2 (Threshold Suffix Guide) where suffix "18" corresponds to 1.8V nominal. This value is laser-trimmed during production and does not require external calibration.
Does the MAX6865UK18D3S+T support active-high or active-low reset output?
The MAX6865UK18D3S+T provides an active-high push-pull RESET output, as indicated by its "65" part number in the Selector Guide and Pin Description section. Pin 1 drives high during reset assertion and low during normal operation - no external pullup resistor is needed.
What is the watchdog timeout period for the MAX6865UK18D3S+T?
The MAX6865UK18D3S+T features a 3.3s typical watchdog timeout period, denoted by the "S" suffix in its order code. Electrical Characteristics table confirms "S" corresponds to min/typ/max of 1.5s/3.3s/7.75s, optimized for detecting firmware stalls in intermittently active embedded systems.
Can the MAX6865UK18D3S+T operate reliably below 1.8V?
Yes - the MAX6865UK18D3S+T guarantees valid RESET operation down to VCC = +1.1V, as specified in Absolute Maximum Ratings and Electrical Characteristics. Its internal circuitry remains functional and asserts RESET correctly even as VCC falls below the 1.8V threshold, enabling controlled shutdown.
Is the MR input of the MAX6865UK18D3S+T internally pulled up?
Yes, the MR input of the MAX6865UK18D3S+T includes an internal 10kΩ pullup resistor to VCC, as documented in the Pin Description and Detailed Description sections. This allows direct connection of a momentary switch from MR to GND without external components, and supports CMOS-level logic drive.
MAX6865UK18D3S+T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Type:
- Simple Reset/Power-On Reset
- Number of Voltages Monitored:
- 1
- Voltage - Threshold:
- 1.8V
- Output:
- Push-Pull, Totem Pole
- Reset:
- Active Low
- Reset Timeout:
- 150ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
MAX6865UK18D3S+T FAQ
1.How can I place an order for MAX6865UK18D3S+T through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX6865UK18D3S+T 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 MAX6865UK18D3S+T reliable?
The price and inventory of MAX6865UK18D3S+T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX6865UK18D3S+T is usually 5 days.
3.What payment methods are accepted for MAX6865UK18D3S+T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX6865UK18D3S+T transactions.
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4.How is shipping managed for MAX6865UK18D3S+T?
MAX6865UK18D3S+T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX6865UK18D3S+T 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 MAX6865UK18D3S+T?
For technical support, including MAX6865UK18D3S+T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX6865UK18D3S+T requirements.
6.How does Aetrix verify that MAX6865UK18D3S+T is sourced from the original manufacturer or authorized distributors?
All MAX6865UK18D3S+T 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 MAX6865UK18D3S+T meets industry standards.
7.What is the process for return or replacement of MAX6865UK18D3S+T?
All MAX6865UK18D3S+T units undergo pre-shipment inspection (PSI). If there is an issue with MAX6865UK18D3S+T, 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 MAX6865UK18D3S+T part is unused and in its original packaging.
Return procedure for MAX6865UK18D3S+T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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