My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX6866UK28D3L+T
- Part No.:
- MAX6866UK28D3L+T
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Supervisors
- Package:
- SC-74A, SOT-753
- Datasheet:
-
MAX6866UK28D3L+T.pdf
- Description:
- IC MPU SUPERVISOR SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,685
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX6866UK28D3L+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, combining voltage monitoring (2.800V factory-trimmed reset threshold), manual reset input (MR), and watchdog timer (209s typical timeout) with ultra-low 170nA typical supply current. It asserts an active-low open-drain RESET output during VCC brownout, MR assertion, or watchdog timeout, supporting battery-powered medical and portable electronics requiring guaranteed reset validity down to VCC = +1.1V.
For engineers reviewing the MAX6866UK28D3L+T datasheet, MAX6866UK28D3L+T pinout, MAX6866UK28D3L+T application, or MAX6866UK28D3L+T equivalent, key selection criteria include its 2.800V ±2.5% reset threshold, 300ms minimum reset timeout (D3), 209s watchdog period (L suffix), open-drain RESET output, and immunity to sub-40µs VCC transients at 100mV overdrive - all validated for -40°C to +85°C operation.
Technical Context
This device integrates a precision bandgap-based voltage monitor, a monostable watchdog timer with edge-triggered clear logic, and a manual reset debounced input with 10kΩ internal pullup. Its reset assertion path guarantees valid output down to VCC = +1.1V, and the watchdog timer clears on any WDI edge (rising or falling), MR assertion, or RESET assertion - ensuring robust recovery from software hangs.
The MAX6866UK28D3L+T belongs to the MAX6864–MAX6869 variant group featuring both MR and WDI inputs, fixed D3 (150–300ms) reset timeout, and L-suffix (95–487s) watchdog timeout. Unlike MAX6861–MAX6863, it lacks CT pin; unlike MAX6867–MAX6869, its WDI is on Pin 4, not Pin 1 - confirming its exact pinout and functional alignment with MAX6864/MAX6866 family specifications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reset Threshold | 2.800V ±2.5% (factory-trimmed); ensures reliable brownout detection for 2.8V nominal supply rails |
| Supply Current | 170nA typical at +25°C; enables multi-year battery life in glucose monitors and wearables |
| Reset Timeout | 150ms min / 300ms typ (D3 option); provides sufficient hold time for µP initialization sequences |
| Watchdog Timeout | 95–487s (L suffix), 209s typical; supports long-loop firmware without excessive watchdog toggling |
| Operating Range | -40°C to +85°C; qualified for industrial and medical portable equipment environments |
| VCC Validity | RESET asserted valid down to VCC = +1.1V; prevents undefined µP state during deep brownout |
| Transient Immunity | Immune to ≤40µs VCC glitches at 100mV overdrive; reduces false resets in noisy power systems |
Pinout & Package
Package: 5-pin SOT23-5, lead-free, surface-mount. Footprint compatible with industry-standard 5-pin SOT23 layouts.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | RESET | Active-low open-drain reset output; requires external pullup; sinks ≥50µA at VCC ≥1.1V |
| 2 | GND | Ground reference; must be connected to system ground plane for noise immunity |
| 3 | MR | Active-low manual reset input; internally pulled up to VCC via 10kΩ; accepts CMOS levels |
| 4 | WDI | Watchdog input; edge-sensitive (150ns min pulse); clears timer on rising/falling transition |
| 5 | VCC | Supply voltage input (1.2V–5.5V); requires 0.1µF bypass capacitor to GND per datasheet |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low ICC | 170nA typical supply current enables >10-year battery life in low-duty-cycle medical devices |
| Guaranteed VCC = +1.1V reset validity | Ensures deterministic µP reset state even during severe brownout conditions |
| Watchdog edge-clear logic | WDI transitions (not level holds) reset timer - prevents stuck-loop masking of faults |
| No external components required | Integrates pullup, timing, and voltage reference - eliminates BOM cost and layout area |
| Open-drain RESET with wide voltage tolerance | RESET pin tolerates up to 5.5V externally - enables level-shifting to higher-voltage µP I/O |
Applications
| Glucose Monitors | Patient Monitoring Wearables |
|---|---|
Use Scenario: Continuous blood glucose sensing with Bluetooth LE transmission and low-power sleep cycles. IC Role / Device Role / Timing Role: Supervisory IC asserting RESET during battery voltage sag or firmware hang, triggered by MR (user button) or WDI (missed sensor polling). Use Value: Prevents corrupted sensor data transmission and ensures safe restart after brownout - critical for FDA Class II device reliability. |
Use Scenario: Ambulatory ECG patch with multi-day battery life and intermittent wireless upload. IC Role / Device Role / Timing Role: Voltage monitor and watchdog enforcing µP reset if main processor fails to toggle WDI within 209s, or if VCC drops below 2.800V during charging transition. Use Value: Guarantees clinical-grade uptime and data integrity without increasing quiescent current beyond 170nA. |
| Industrial Handheld Scanners | Smart Energy Meters |
Use Scenario: Rugged barcode scanner operating from primary lithium battery with cold-temperature exposure. IC Role / Device Role / Timing Role: Brownout detector holding µP in reset until VCC stabilizes above 2.800V after cold-start; MR enables field-service hard reset. Use Value: Eliminates boot failures at -25°C by validating reset down to VCC = +1.1V - matching battery discharge curve. |
Use Scenario: Tamper-resistant electricity meter with secure bootloader and periodic firmware updates. IC Role / Device Role / Timing Role: Watchdog supervisor preventing infinite loops during cryptographic signature verification; D3 timeout ensures full bootloader execution before release. Use Value: Meets IEC 62056-21 security requirements by guaranteeing fail-safe reset on code execution error - no external RC timing needed. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar microprocessor supervisory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX6864UK28D3L+T | Identical reset threshold (2.800V), timeout (D3), and watchdog (L), but push-pull active-low RESET output instead of open-drain | Requires no external pullup; unsuitable where level-shifting or wired-OR reset bus is needed | Select MAX6864UK28D3L+T only if system uses single-supply reset net and does not require voltage translation. |
| TPS3838K28DBVR | Same 2.8V threshold and SOT23-5 package, but no watchdog timer; 200ms fixed reset timeout; 1.2µA supply current | Lacks WDI functionality - cannot supervise firmware execution; higher ICC reduces battery life | Choose TPS3838K28DBVR only for cost-sensitive, non-watchdog applications where 1.2µA ICC is acceptable. |
Compared with MAX6864UK28D3L+T, the MAX6866UK28D3L+T's open-drain RESET enables flexible voltage-level interfacing and wired-OR reset buses, while versus TPS3838K28DBVR, its 170nA ICC and integrated watchdog deliver superior battery longevity and runtime fault coverage in safety-critical portable systems.
Availability
The MAX6866UK28D3L+T is available at Aetrix Electronics and suitable for glucose monitors, patient wearables, industrial handheld scanners, and smart energy meters requiring stable component supply across extended product lifecycles.
Supply support for MAX6866UK28D3L+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, sensing, and interface applications in industrial, medical, and communications markets.
The MAX6864–MAX6869 family was engineered specifically for ultra-low-power microprocessor supervision in battery-constrained medical and portable electronics, integrating voltage monitoring, manual reset, and configurable watchdog functionality in minimal footprint.
FAQ
What is the exact reset threshold voltage of the MAX6866UK28D3L+T?
The MAX6866UK28D3L+T has a factory-trimmed reset threshold of 2.800V, with ±2.5% tolerance over temperature (-40°C to +85°C). This value is confirmed in Table 2 (Threshold Suffix Guide) of the datasheet, where suffix "28" corresponds to 2.800V nominal. The MAX6866UK28D3L+T maintains this accuracy without external calibration.
Does the MAX6866UK28D3L+T support active-high reset output?
No, the MAX6866UK28D3L+T features an active-low open-drain RESET output only. Unlike MAX6865/MAX6868 variants, it does not offer push-pull active-high configuration. The open-drain design requires an external pullup resistor and enables voltage-level translation - a deliberate feature for interoperability with diverse µP I/O voltages.
What is the watchdog timeout behavior of the MAX6866UK28D3L+T?
The MAX6866UK28D3L+T implements a 209s typical watchdog timeout (L suffix), with min/max range of 95s–487s. The timer clears on any WDI edge (rising or falling), MR assertion, or RESET assertion - ensuring it cannot be masked by stuck firmware loops. This behavior is explicitly defined in Table 3 and Figure 3 of the MAX6866UK28D3L+T datasheet.
Can the MAX6866UK28D3L+T operate reliably at VCC = 1.2V?
Yes, the MAX6866UK28D3L+T is fully specified to operate at VCC = 1.2V minimum, with guaranteed RESET assertion validity down to VCC = +1.1V. Electrical Characteristics table confirms supply voltage range of 1.2V to 5.5V, and the "VCC Reset Threshold" parameter is tested across this full range - making it suitable for single-cell Li-ion or LiFePO₄ systems under load.
Is the MAX6866UK28D3L+T pin-compatible with other MAX68xx supervisory ICs?
The MAX6866UK28D3L+T shares the identical 5-pin SOT23-5 pinout with MAX6864/MAX6865/MAX6866 variants (Pin 1: RESET, Pin 2: GND, Pin 3: MR, Pin 4: WDI, Pin 5: VCC). It is not pin-compatible with MAX6861–MAX6863 (which use Pin 1 for CT) or MAX6867–MAX6869 (which place WDI on Pin 1). This alignment is verified in the "MAX6864/MAX6865/MAX6866 Pin Description" section.
MAX6866UK28D3L+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:
- 2.8V
- 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
MAX6866UK28D3L+T FAQ
1.How can I place an order for MAX6866UK28D3L+T through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX6866UK28D3L+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 MAX6866UK28D3L+T reliable?
The price and inventory of MAX6866UK28D3L+T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX6866UK28D3L+T is usually 5 days.
3.What payment methods are accepted for MAX6866UK28D3L+T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX6866UK28D3L+T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX6866UK28D3L+T?
MAX6866UK28D3L+T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX6866UK28D3L+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 MAX6866UK28D3L+T?
For technical support, including MAX6866UK28D3L+T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX6866UK28D3L+T requirements.
6.How does Aetrix verify that MAX6866UK28D3L+T is sourced from the original manufacturer or authorized distributors?
All MAX6866UK28D3L+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 MAX6866UK28D3L+T meets industry standards.
7.What is the process for return or replacement of MAX6866UK28D3L+T?
All MAX6866UK28D3L+T units undergo pre-shipment inspection (PSI). If there is an issue with MAX6866UK28D3L+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 MAX6866UK28D3L+T part is unused and in its original packaging.
Return procedure for MAX6866UK28D3L+T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX6866UK28D3L+T 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…
