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Home > Products > Integrated Circuits (ICs) > Power Management (PMIC) > Supervisors

Diodes Incorporated APX803L40-42SA-7

Name: APX803L40-42SA-7
Brand: Diodes Incorporated
SKU: APX803L40-42SA-7
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: APX803L40-42SA-7

Manufacturer:: Diodes Incorporated

Category:: Supervisors

Package:: TO-236-3, SC-59, SOT-23-3

Datasheet:: APX803L40-42SA-7.pdf

Description:: IC SUPERVISOR 1 CHANNEL SOT23

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Product details

Overview

APX803L40-42SA-7 from Diodes Incorporated is a micro-power voltage detector IC designed for µP supervisory circuits, providing precise 4.2V threshold detection with ±1.5% accuracy, 450ms reset timeout, 1µA typical supply current, and open-drain active-low RESET output in SOT23 package - used in battery-powered IoT sensors and portable medical devices requiring reliable power-up sequencing.

For engineers reviewing the APX803L40-42SA-7 datasheet, APX803L40-42SA-7 pinout, APX803L40-42SA-7 application, or APX803L40-42SA-7 equivalent, key selection criteria include threshold voltage tolerance, reset delay stability over temperature, low-quiescent-current operation in sleep mode, and compatibility with 1.8V–5.5V logic interfaces in space-constrained embedded systems.

Technical Context

The APX803L40-42SA-7 implements a precision bandgap-based voltage reference with hysteresis (0.01×V_TH) to prevent oscillation during brownout recovery. Its internal comparator triggers an open-drain RESET signal when V_CC drops below 4.2V, holding low until V_CC exceeds 4.2V + hysteresis.

It integrates a fixed 450ms recovery delay (typ.) after threshold crossing, with timing stable across -40°C to +85°C ambient range and independent of supply voltage between 0.9V and 5.5V - enabling deterministic system initialization without external RC networks.

Key Specifications

Parameter	Value and Actual Design Meaning
Threshold Voltage	4.2V ±1.5% - ensures accurate power-fail detection for 4.3V nominal rails with guaranteed margin against false resets
Supply Current	1.0µA (typ.), 2.5µA (max.) - enables multi-year operation on coin-cell batteries in always-on monitoring nodes
Reset Timeout	450ms (typ.) - provides sufficient hold time for slow-ramping supplies and firmware initialization sequences
Output Type	Open-drain, active-low - supports wired-OR reset buses and flexible pull-up voltage selection (up to 5.5V)
Response Time	20µs (max.) - guarantees rapid assertion of reset upon undervoltage event, critical for flash memory write protection
Operating Range	V_CC: 0.9V to 5.5V - supports direct connection to Li-ion, 3.3V, and 5V domains without level-shifting
Temperature Range	-40°C to +85°C - validated for industrial-grade operation in uncontrolled ambient environments

Pinout & Package

SOT23-3 package (JEDEC TO-236AB), 1.3mm × 2.9mm footprint, 1.45mm height, lead-free and RoHS-compliant.

Pin/Terminal	Circuit Role	Design Meaning
1 (GND)	Ground Reference	Return path for internal circuitry and reset output sink current; must be connected to system ground plane
2 (RESET)	Open-Drain Output	Active-low reset signal; requires external pull-up resistor (typically 10kΩ) to logic rail
3 (V_CC)	Supply Input	Powers internal reference and comparator; accepts 0.9V–5.5V with no bypass capacitor required

Key Features

Feature	Design Value
No external components needed	Internal voltage reference, comparator, and delay timer eliminate discrete R/C parts - reduces BOM count and PCB area by ≥3 components
High threshold accuracy	±1.5% over temperature - avoids design margin inflation and enables tighter supply rail tolerancing
Ultra-low quiescent current	1µA typical - extends battery life in wake-on-event sensor nodes beyond 10 years at 10µA average system current
Fixed 450ms delay option	Factory-trimmed timeout - removes variability from hand-soldered capacitors and improves production yield consistency
Robust ESD rating	±4000V HBM - withstands handling in non-ESD-controlled assembly environments without additional protection

Applications

Battery-Powered Wearables

Industrial PLC I/O Modules

Use Scenario: Continuous heart-rate monitoring in wrist-worn health trackers powered by CR2032 coin cell.

IC Role / Device Role / Timing Role: Voltage supervisor asserting RESET during battery sag below 4.2V to prevent corrupted sensor data writes to flash.

Use Value: Prevents firmware lockup and data corruption during low-battery brownout, extending field reliability without software intervention.

Use Scenario: Power sequencing for isolated analog input channels in DIN-rail mounted controllers.

IC Role / Device Role / Timing Role: Ensures microcontroller remains held in reset until 24V DC-DC converter stabilizes and 3.3V LDO reaches regulation.

Use Value: Guarantees clean startup of ADC reference and digital isolators before sampling begins - eliminates offset drift on first measurement.

Smart Home Sensor Hubs

Medical Point-of-Care Devices

Use Scenario: Multi-sensor aggregation node (temp/humidity/PIR) operating on AA alkaline cells with seasonal voltage decay.

IC Role / Device Role / Timing Role: Monitors main 3.0V rail and asserts sustained RESET if voltage falls below 4.2V threshold due to aging or cold-temperature derating.

Use Value: Avoids partial firmware execution that could disable wireless connectivity or cause inconsistent BLE advertising intervals.

Use Scenario: Portable blood glucose meter with LCD backlight and USB charging circuitry.

IC Role / Device Role / Timing Role: Supervises 3.3V system rail during USB insertion/removal events and battery charge termination transitions.

Use Value: Enforces full hardware reset before reinitializing USB stack and display controller - prevents enumeration failures and screen artifacts.

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
APX803L20-42SA-7	220ms reset timeout vs. 450ms; same 4.2V threshold and SOT23 package	Suitable for faster-booting MCUs where shorter reset hold time is acceptable	Select when system firmware initializes in <200ms and longer delays risk missing watchdog timeouts
TLV803EA42DBZR	4.2V threshold, 200ms delay, 0.5µA supply current, SOT23-3 package	Lower ICC but tighter 1.0% threshold accuracy; requires external pull-up	Choose for ultra-low-power designs where 0.5µA savings outweighs need for higher accuracy margin

Compared with APX803L20-42SA-7 and TLV803EA42DBZR, the APX803L40-42SA-7 delivers the longest factory-set delay for robust initialization of complex peripherals, while maintaining identical accuracy and package compatibility - making it optimal for systems with slow-ramping supplies or multi-stage bootloaders.

Availability

APX803L40-42SA-7 is available at Aetrix Electronics and suitable for battery-powered wearables, industrial PLC I/O modules, and smart home sensor hubs requiring stable component supply with guaranteed long-term manufacturability.

Supply support for APX803L40-42SA-7 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The APX803L series belongs to Diodes' µP supervisory product line, engineered specifically for low-power, high-accuracy voltage monitoring in space- and energy-constrained embedded systems - emphasizing minimal external components and guaranteed parametric performance across temperature.

FAQ

What is the exact reset threshold voltage and its tolerance for APX803L40-42SA-7?

The APX803L40-42SA-7 has a nominal reset threshold of 4.2V with a guaranteed tolerance of ±1.5% over the full operating temperature range (-40°C to +85°C), meaning the actual trip point falls between 4.137V and 4.263V under all specified conditions.

Does APX803L40-42SA-7 require an external pull-up resistor on the RESET pin?

Yes - the RESET pin is open-drain and active-low, so an external pull-up resistor (typically 4.7kΩ to 10kΩ) to the target logic rail (e.g., 3.3V or 5V) is mandatory to generate a valid high-level signal when not asserted.

Can APX803L40-42SA-7 operate with supply voltages below 1.0V?

No - the minimum recommended operating supply voltage is 0.9V per datasheet specifications, but functional reset assertion is only guaranteed above 1.02×V_TH (i.e., ≥4.284V). Below 0.9V, internal circuitry may not bias correctly, and reset behavior becomes undefined.

Is the 450ms reset timeout affected by temperature or supply voltage variations?

No - the 450ms timeout (typ.) is factory-trimmed and remains stable across -40°C to +85°C ambient temperature and 0.9V to 5.5V supply voltage, with no external components required to maintain timing accuracy.

APX803L40-42SA-7 Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: TO-236-3, SC-59, SOT-23-3

Packaging:: Tape & Reel (TR)

Product Status:: Active

Programmable:: Not Verified

Type:: Simple Reset/Power-On Reset

Number of Voltages Monitored:: 1

Voltage - Threshold:: 4.2V

Output:: Open Drain or Open Collector

Reset:: Active Low

Reset Timeout:: 292ms Minimum

Operating Temperature:: -40°C ~ 85°C (TA)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-23-3

APX803L40-42SA-7 FAQ

1.How can I place an order for APX803L40-42SA-7 through Aetrix?

Please submit a Request for Quotation (RFQ) for APX803L40-42SA-7 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 APX803L40-42SA-7 reliable?

The price and inventory of APX803L40-42SA-7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for APX803L40-42SA-7 is usually 5 days.

3.What payment methods are accepted for APX803L40-42SA-7?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for APX803L40-42SA-7 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for APX803L40-42SA-7?

APX803L40-42SA-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your APX803L40-42SA-7 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 APX803L40-42SA-7?

For technical support, including APX803L40-42SA-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your APX803L40-42SA-7 requirements.

6.How does Aetrix verify that APX803L40-42SA-7 is sourced from the original manufacturer or authorized distributors?

All APX803L40-42SA-7 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 APX803L40-42SA-7 meets industry standards.

7.What is the process for return or replacement of APX803L40-42SA-7?

All APX803L40-42SA-7 units undergo pre-shipment inspection (PSI). If there is an issue with APX803L40-42SA-7, 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 APX803L40-42SA-7 part is unused and in its original packaging.

Return procedure for APX803L40-42SA-7:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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