My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX6728AKASHD3+T
- Part No.:
- MAX6728AKASHD3+T
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Supervisors
- Package:
- -
- Datasheet:
-
MAX6728AKASHD3+T.pdf
- Description:
- IC SUPERVISOR MPU SOT23-8
- Quantity:
- Payment:
- Shipping:
Inventory:3,455
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX6728AKASHD3+T from Maxim Integrated is a dual-supply ultra-low-voltage microprocessor supervisory circuit with power-fail monitoring, factory-trimmed VCC1/VCC2 reset thresholds (4.625V/3.075V), 280ms reset timeout, and open-drain RST/PFO outputs. It monitors primary (1.8–5.0V) and secondary (0.9–3.3V) supplies while guaranteeing valid reset logic down to VCC1 or VCC2 = 0.8V - used in telecom power management systems requiring reliable brownout detection and orderly shutdown.
For engineers reviewing the MAX6728AKASHD3+T datasheet, MAX6728AKASHD3+T pinout, MAX6728AKASHD3+T application, or MAX6728AKASHD3+T equivalent, key selection criteria include its dual-supply monitoring capability, PFI/PFO power-fail interface, 280ms reset timeout, -40°C to +125°C operation, and SOT23-8 package compatibility with multivoltage industrial and networking equipment.
Technical Context
This device integrates two independent voltage comparators for VCC1 and VCC2, a dedicated power-fail comparator (PFI → PFO), manual-reset input (MR), and open-drain active-low reset output (RST) and power-fail output (PFO). All reset functions assert when either supply falls below its threshold and hold for the 280ms timeout period after recovery.
The PFI input uses a 626.5mV internal reference to detect supply droop; PFO deasserts immediately without timeout. MR features a 50kΩ internal pullup to VCC1 and supports CMOS-level triggering. The device draws only 10–39µA total supply current and operates across the full automotive-grade temperature range (-40°C to +125°C).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC1 Reset Threshold | 4.625V (typ), factory-trimmed - ensures reliable reset assertion before 5V system rail collapse |
| VCC2 Reset Threshold | 3.075V (typ), factory-trimmed - matches common 3.3V I/O or core supply trip point |
| Reset Timeout Period | 280ms (min) - provides sufficient hold time for processor initialization and firmware boot sequence |
| PFI Input Threshold | 626.5mV (typ) - enables precise external resistor-divider setup for custom power-fail detection |
| Supply Current | 10µA (typ at VCC1 < 3.6V) - minimizes quiescent load on battery-backed or low-power auxiliary rails |
| Operating Temperature | -40°C to +125°C - qualified for under-hood automotive, industrial control, and telecom base station use |
| Output Type | Open-drain RST and PFO - allows wired-OR configuration and flexible pullup voltage selection |
Pinout & Package
MAX6728AKASHD3+T is housed in an 8-pin SOT23 package (package code K8SN+1, outline 21-0078), with thermal resistance θJA = 180°C/W on multilayer board.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - RST | Active-low reset output | Open-drain output asserted when VCC1/VCC2 drops below threshold or MR pulled low; requires external pullup |
| 2 - GND | Ground reference | Common return path for all internal comparators and logic; must be low-impedance connection |
| 3 - MR | Manual-reset input | Active-low input with 50kΩ internal pullup to VCC1; initiates reset on falling edge and holds for full timeout |
| 4 - PFO | Active-low power-fail output | Open-drain output asserted when PFI < 626.5mV; deasserts immediately on recovery (no timeout) |
| 5 - VCC2 | Secondary supply input | Powers internal circuitry when VCC2 > VCC1; monitored by second comparator for 0.9–3.3V rails |
| 6 - VCC1 | Primary supply input | Main power source and reference for MR pullup, RST/PFO drive, and first comparator (1.8–5.0V) |
| 7 - PFI | Power-fail monitor input | High-impedance input referenced to 626.5mV; used with resistor divider to detect auxiliary supply droop |
| 8 - NC | No connect | Pin 8 is internally unused and must remain unconnected per datasheet; no routing or grounding required |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent supply monitoring | Simultaneous VCC1 (1.8–5.0V) and VCC2 (0.9–3.3V) supervision with separate thresholds and hysteresis |
| Power-fail detection with immediate response | PFI→PFO path has 2µs typical delay and zero timeout - enables real-time warning before system shutdown |
| Guaranteed reset validity down to 0.8V | Ensures correct RST/PFO logic state even during deep brownout, critical for fail-safe embedded control |
| Low-quiescent-current design | 10µA typical ICC1 at VCC1 < 3.6V - extends battery life in portable or backup-power applications |
| SOT23-8 automotive-qualified package | K8SN+1 footprint supports high-density PCB layout and meets AEC-Q100 stress requirements |
Applications
| Telecom Power Management | Industrial PLC Power Sequencing |
|---|---|
|
Use Scenario: Monitoring redundant 5V/3.3V DC-DC outputs in a 48V-powered telecom shelf with early power-fail alerting. IC Role / Device Role / Timing Role: Dual-supply supervisor asserting RST on rail collapse and PFO on preregulator droop to trigger graceful software shutdown. Use Value: Prevents data corruption during AC loss by initiating controlled reboot within 280ms of fault detection. |
Use Scenario: Ensuring safe startup/shutdown sequencing of FPGA, MCU, and analog I/O rails in modular PLC backplane. IC Role / Device Role / Timing Role: Coordinating reset timing across three voltage domains using VCC1/VCC2 thresholds and MR for operator-initiated reset. Use Value: Eliminates race conditions during cold start by holding all subsystems in reset until all rails stabilize above trip points. |
| Automotive ADAS Camera Module | Network Equipment Hot-Swap Control |
|
Use Scenario: Supervising 12V-to-3.3V/1.8V conversion chain in an automotive camera ECU operating at -40°C to +125°C. IC Role / Device Role / Timing Role: Providing AEC-Q100-compliant reset generation and brownout immunity for image sensor and ISP power domains. Use Value: Maintains functional safety integrity by guaranteeing reset assertion even during engine cranking transients (VCC ≥ 0.8V). |
Use Scenario: Managing power sequencing and fault response in hot-swappable line cards of carrier-grade switches/routers. IC Role / Device Role / Timing Role: Using PFI to monitor intermediate bus voltage and PFO to signal upstream power controller before catastrophic failure. Use Value: Enables predictive maintenance by converting analog supply margin into digital interrupt before undervoltage lockout occurs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-supply supervisory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX6729AKASHD3+T | Same pinout and electrical specs, but includes watchdog timer (WDI input); adds 35s startup + 1.12s normal timeout modes | Required where software execution monitoring is needed alongside power supervision | Select MAX6729AKASHD3+T if watchdog functionality is mandatory; otherwise MAX6728AKASHD3+T reduces BOM count and simplifies firmware |
| TPS3808G33DBVR | Single-supply (3.3V only), no PFI/PFO, fixed 3.08V threshold, 200ms timeout, SOT23-6 package | Limited to single-rail systems without power-fail signaling or secondary supply monitoring | Choose TPS3808G33DBVR only for cost-sensitive, single-voltage designs lacking PFI or VCC2 requirements |
Compared with MAX6729AKASHD3+T, the MAX6728AKASHD3+T omits watchdog circuitry to reduce complexity and cost where software monitoring is unnecessary; versus TPS3808G33DBVR, it delivers true dual-supply supervision and power-fail alerting in the same compact SOT23-8 footprint.
Availability
MAX6728AKASHD3+T is available at Aetrix Electronics and suitable for telecom infrastructure, industrial PLCs, automotive ADAS modules, and network equipment requiring stable component supply across extended temperature and long product lifecycles.
Supply support for MAX6728AKASHD3+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, mixed-signal, and power management ICs for demanding industrial, automotive, and communications applications.
The MAX6715A–MAX6729A family delivers ultra-low-voltage supervisory circuits optimized for multivoltage embedded systems requiring guaranteed reset behavior, power-fail detection, and AEC-Q100 compliance.
FAQ
What is the exact reset timeout period for MAX6728AKASHD3+T?
The MAX6728AKASHD3+T has a guaranteed minimum reset timeout period of 280ms (D3 suffix). This value is factory-trimmed and specified over the full -40°C to +125°C temperature range. The actual timeout may extend up to 350ms depending on process variation and operating conditions, but will never fall below 280ms.
Does MAX6728AKASHD3+T support monitoring a third voltage rail?
No, MAX6728AKASHD3+T does not include an RSTIN input for adjustable third-rail monitoring. That feature is present only in variants like MAX6723A–MAX6727A. MAX6728AKASHD3+T is strictly a dual-supply supervisor with VCC1 and VCC2 inputs plus PFI for auxiliary power-fail detection.
Can MAX6728AKASHD3+T be used in automotive applications?
Yes, MAX6728AKASHD3+T operates from -40°C to +125°C and is built on the same platform as AEC-Q100-qualified parts (e.g., MAX6719AUTTWD1/V+T). While the MAX6728AKASHD3+T itself is not individually certified, its design, test coverage, and qualification pedigree make it suitable for automotive ADAS and body electronics where full AEC-Q100 documentation is not mandated.
What is the function of Pin 8 (NC) on MAX6728AKASHD3+T?
Pin 8 on MAX6728AKASHD3+T is a no-connect (NC) terminal. It is not bonded internally and must remain unconnected on the PCB. Routing traces to or placing solder on Pin 8 violates the device's validated land pattern (90-0176) and may cause mechanical stress or unintended coupling.
How does the PFI-to-PFO path differ from the VCC1/VCC2 reset path in MAX6728AKASHD3+T?
In MAX6728AKASHD3+T, the PFI-to-PFO path asserts PFO immediately when PFI falls below 626.5mV and deasserts PFO instantly upon recovery - no timeout is applied. In contrast, VCC1/VCC2 faults trigger RST with a mandatory 280ms minimum timeout, ensuring sustained reset hold time regardless of transient recovery speed.
MAX6728AKASHD3+T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- *
- Package/Case:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- -
- Number of Voltages Monitored:
- -
- Voltage - Threshold:
- -
- Output:
- -
- Reset:
- -
- Reset Timeout:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- -
- Supplier Device Package:
- -
MAX6728AKASHD3+T FAQ
1.How can I place an order for MAX6728AKASHD3+T through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX6728AKASHD3+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 MAX6728AKASHD3+T reliable?
The price and inventory of MAX6728AKASHD3+T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX6728AKASHD3+T is usually 5 days.
3.What payment methods are accepted for MAX6728AKASHD3+T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX6728AKASHD3+T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX6728AKASHD3+T?
MAX6728AKASHD3+T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX6728AKASHD3+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 MAX6728AKASHD3+T?
For technical support, including MAX6728AKASHD3+T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX6728AKASHD3+T requirements.
6.How does Aetrix verify that MAX6728AKASHD3+T is sourced from the original manufacturer or authorized distributors?
All MAX6728AKASHD3+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 MAX6728AKASHD3+T meets industry standards.
7.What is the process for return or replacement of MAX6728AKASHD3+T?
All MAX6728AKASHD3+T units undergo pre-shipment inspection (PSI). If there is an issue with MAX6728AKASHD3+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 MAX6728AKASHD3+T part is unused and in its original packaging.
Return procedure for MAX6728AKASHD3+T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX6728AKASHD3+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…
