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

Diodes Incorporated APX803L-42SA-7

Name: APX803L-42SA-7
Brand: Diodes Incorporated
SKU: APX803L-42SA-7
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: APX803L-42SA-7

Manufacturer:: Diodes Incorporated

Category:: Supervisors

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

Datasheet:: APX803L-42SA-7.pdf

Description:: IC SUPERVISOR 1 CHANNEL SOT23

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Product details

Overview

APX803L-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, 1µA typical supply current, and 220ms reset timeout. It features open-drain active-low RESET output and operates across -40°C to +85°C ambient range in portable battery-powered systems.

For engineers reviewing the APX803L-42SA-7 datasheet, APX803L-42SA-7 pinout, APX803L-42SA-7 application, or APX803L-42SA-7 equivalent, key selection criteria include fixed 4.2V detection level, SOT23-3 package compatibility, 220ms recovery delay timing, and low-quiescent-current supervision for power-sensitive embedded controllers and IoT endpoints.

Technical Context

The APX803L-42SA-7 implements a precision bandgap-based voltage reference with internal hysteresis (0.01×V_TH) to prevent oscillation during V_CC transitions near threshold. Its comparator drives an open-drain output stage capable of sinking ≥3.5mA at 0.4V drop.

Reset assertion occurs within 20µs after V_CC falls below 4.2V, and release requires V_CC to exceed 4.2V × (1 + hysteresis), ensuring stable deassertion. The 220ms timeout (APX803L20 variant) is factory-programmed and temperature-stable across -40°C to +85°C.

Key Specifications

Parameter	Value and Actual Design Meaning
Detection Threshold	4.2V ±1.5% - precisely monitors 4.2V Li-ion battery full-charge or system rail stability
Supply Current	1.0µA typical - enables multi-year operation in coin-cell–powered devices
Reset Timeout	220ms - ensures reliable processor initialization after brownout recovery
Output Type	Open-drain, active-low - supports wired-OR reset bus and flexible pull-up voltage selection
Response Time	20µs max - guarantees fast fault detection before MCU state corruption
Operating Temp	-40°C to +85°C - qualified for industrial and consumer-grade embedded applications
Package	SOT23-3 - surface-mount footprint compatible with high-density PCB layouts

Pinout & Package

SOT23-3 package with 1.3mm × 2.9mm footprint, 0.95mm height, and gull-wing leads. RoHS-compliant, lead-free, halogen-free construction.

Pin/Terminal	Circuit Role	Design Meaning
1 (GND)	Ground Reference	Return path for internal circuitry and output sink current; must connect to system ground plane
2 (RESET)	Open-Drain Output	Active-low reset signal; requires external pull-up resistor to host V_CC or logic rail
3 (V_CC)	Supply Input	Power input for detector operation; accepts 0.9V–5.5V, enabling use on 1.8V–5V rails

Key Features

Feature	Design Value
Fixed 4.2V threshold	Factory-trimmed detection point eliminates external resistor network and calibration effort
220ms built-in delay	Guaranteed minimum reset pulse width without external RC timing components
±1.5% threshold accuracy	Reduces design margin requirements versus ±3% alternatives, improving system voltage headroom
1µA supply current	Minimizes standby power draw in always-on monitoring applications such as smart sensors
No external components	Self-contained supervision reduces BOM count, layout area, and qualification testing scope

Applications

Battery Management System

Microcontroller Supervision

Use Scenario: Monitoring single-cell Li-ion battery voltage during charge termination and discharge protection.

IC Role / Device Role / Timing Role: Voltage detector asserting RESET when cell voltage drops below 4.2V during over-discharge or rises above 4.2V at full charge.

Use Value: Prevents deep discharge damage and enables safe recharging by coordinating with charger IC via reset signaling.

Use Scenario: Ensuring clean boot sequence for ARM Cortex-M0+ microcontrollers in industrial gateways.

IC Role / Device Role / Timing Role: Generating 220ms active-low reset pulse upon power-up or brownout to hold MCU in reset until V_CC stabilizes.

Use Value: Eliminates need for discrete RC reset circuit, reducing component count and improving timing repeatability across temperature.

Portable Medical Sensor

Smart Home Hub Power Sequencing

Use Scenario: Supervising 3.3V supply rail in FDA-cleared wearable ECG sensor with coin-cell backup.

IC Role / Device Role / Timing Role: Detecting 4.2V auxiliary rail collapse and triggering controlled shutdown before data loss.

Use Value: 1µA quiescent current extends battery life beyond 3 years while maintaining fail-safe supervision.

Use Scenario: Coordinating power-up sequence between Wi-Fi SoC, memory, and peripheral ASICs in voice-controlled hub.

IC Role / Device Role / Timing Role: Providing synchronized 220ms reset assertion to all subsystems after main 5V rail reaches regulation.

Use Value: Resolves race conditions in multi-rail systems where individual LDOs have varying startup delays.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
APX803L20-42SR-7	Same 4.2V threshold and 220ms delay, but SOT23R (reversed pinout: Pin1=GND, Pin2=V_CC, Pin3=RESET)	Requires PCB layout revision due to swapped V_CC/GND pins; identical electrical behavior	Select only if redesigning board for improved thermal relief or legacy SOT23R footprint compatibility
TLV803E42DBZR	4.2V threshold, 200ms delay (not 220ms), 0.5µA I_CC, same SOT23-3 package	Shorter timeout may not meet minimum reset hold time for some MCUs; lower current benefits ultra-low-power designs	Prefer when 200ms suffices and sub-1µA supply current is critical; verify MCU reset timing spec compliance

Compared with APX803L20-42SR-7, the APX803L-42SA-7 offers standard SOT23 pinout for drop-in replacement in existing layouts; versus TLV803E42DBZR, it provides tighter 220ms timing alignment with Diodes' validated MCU boot sequences and higher sink current capability.

Availability

APX803L-42SA-7 is available at Aetrix Electronics and suitable for battery management systems, microcontroller supervision, portable medical sensors, and smart home hub power sequencing requiring stable component supply and long-term production continuity.

Supply support for APX803L-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 semiconductor company specializing in discrete, analog, and mixed-signal ICs for power management, signal integrity, and connectivity applications.

The APX803L series belongs to Diodes' µP supervisory product line, engineered specifically for ultra-low-power, high-accuracy voltage monitoring in space-constrained and energy-sensitive embedded systems.

FAQ

What is the exact reset threshold voltage and tolerance for APX803L-42SA-7?

The APX803L-42SA-7 has a nominal reset threshold of 4.2V with ±1.5% accuracy over temperature (–40°C to +85°C), meaning the actual trip point falls between 4.137V and 4.263V at 25°C. This is factory-trimmed and does not require external calibration.

Does APX803L-42SA-7 require external components to function?

No. The APX803L-42SA-7 operates autonomously with only V_CC, GND, and RESET connections. An external pull-up resistor on the open-drain RESET pin is required for proper logic-level translation, but no timing capacitors or resistors are needed for threshold or delay functions.

Can APX803L-42SA-7 monitor voltages below its 4.2V threshold?

No. The APX803L-42SA-7 is a fixed-threshold device set exclusively to 4.2V. It cannot be adjusted or reconfigured for other voltages. For 3.3V or 2.5V supervision, Diodes offers APX803L-33SA-7 or APX803L-25SA-7 variants respectively.

What is the maximum sink current capability of the RESET output?

The RESET pin can sink up to 20mA continuously (absolute maximum rating), with a guaranteed low-level voltage ≤0.4V at 3.5mA sink current. This allows direct interfacing with most 1.8V–5V logic families using appropriate pull-up resistors.

APX803L-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:: -

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

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-23-3

APX803L-42SA-7 FAQ

1.How can I place an order for APX803L-42SA-7 through Aetrix?

Please submit a Request for Quotation (RFQ) for APX803L-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 APX803L-42SA-7 reliable?

The price and inventory of APX803L-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 APX803L-42SA-7 is usually 5 days.

3.What payment methods are accepted for APX803L-42SA-7?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for APX803L-42SA-7 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for APX803L-42SA-7?

APX803L-42SA-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your APX803L-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 APX803L-42SA-7?

For technical support, including APX803L-42SA-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your APX803L-42SA-7 requirements.

6.How does Aetrix verify that APX803L-42SA-7 is sourced from the original manufacturer or authorized distributors?

All APX803L-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 APX803L-42SA-7 meets industry standards.

7.What is the process for return or replacement of APX803L-42SA-7?

All APX803L-42SA-7 units undergo pre-shipment inspection (PSI). If there is an issue with APX803L-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 APX803L-42SA-7 part is unused and in its original packaging.

Return procedure for APX803L-42SA-7:

1.Submit a request within 90 days.

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

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