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Home > Products > Integrated Circuits (ICs) > Interface > I/O Expanders

Diodes Incorporated PI4IOE5V9539LE

Name: PI4IOE5V9539LE
Brand: Diodes Incorporated
SKU: PI4IOE5V9539LE
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: PI4IOE5V9539LE

Manufacturer:: Diodes Incorporated

Category:: I/O Expanders

Package:: 24-TSSOP (0.173", 4.40mm Width)

Datasheet:: PI4IOE5V9539LE.pdf

Description:: IC XPNDR 400KHZ I2C 24TSSOP

Quantity:: RFQ Add To RFQ list

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Product details

Overview

PI4IOE5V9539LE from Diodes Incorporated is a 16-bit I²C/SMBus GPIO expander with interrupt and active-low reset, operating from 2.3V to 5.5V, featuring 5V-tolerant I/Os, open-drain INT output, and dual 8-bit configuration/polarity registers. It serves as a parallel I/O extension for embedded control in ACPI power switches, push-button interfaces, LED drivers, and sensor monitoring systems.

For engineers reviewing the PI4IOE5V9539LE datasheet, PI4IOE5V9539LE pinout, PI4IOE5V9539LE application, or PI4IOE5V9539LE equivalent, key selection criteria include I²C address flexibility (A0/A1), 400 kHz Fast Mode support, low standby current (0.25 µA), 5V I/O tolerance, and dual-package availability (TSSOP-24/TQFN-24).

Technical Context

The device implements two independent 8-bit I/O ports (Port 0 and Port 1), each with configurable direction (via Configuration registers), polarity inversion (Polarity registers), and input state mirroring (Input Port registers). All 16 I/Os default to high-impedance inputs at power-on reset or active-low RESET assertion.

Interrupt generation is edge-sensitive and port-specific: INT activates only when an input-configured pin changes state, and clears only upon reading the corresponding Input Port register - not the other port. The open-drain INT output requires external pull-up and supports wired-OR bus sharing.

Key Specifications

Parameter	Value and Actual Design Meaning
Supply Voltage	2.3 V to 5.5 V - enables direct interface with 3.3 V and 5 V logic domains without level shifters.
I²C Clock Frequency	0–400 kHz - supports Standard and Fast Mode I²C, compatible with most microcontroller peripherals.
Standby Current	0.25 µA typical at 5.5 V - critical for battery-powered systems requiring ultra-low quiescent power.
I/O Voltage Tolerance	Up to 6.0 V on I/O pins - allows safe interfacing with 5 V signals while powered from 3.3 V or lower.
Output Drive Strength	8–11 mA sink per I/O at VOL = 0.5–0.7 V - sufficient to directly drive LEDs or small logic loads.
Interrupt Latency	4 µs max valid time (tv(INT)) - ensures timely system response to input events like button presses.
ESD Protection	4 kV HBM / 1 kV CDM - meets industrial-grade robustness requirements for board-level ESD immunity.

Pinout & Package

PI4IOE5V9539LE is offered in two RoHS-compliant, lead-free packages: 24-pin TSSOP (173 mil width) and 24-contact TQFN (4 mm × 4 mm, 0.5 mm pitch). Both packages support reflow soldering and provide identical pin functionality and electrical characteristics.

Pin/Terminal	Circuit Role	Design Meaning
INT (Pin 1 / TSSOP; Pin 22 / TQFN)	Open-drain interrupt output	Asserts LOW when any input-configured I/O changes state; requires external pull-up for proper logic level.
RESET (Pin 3 / TSSOP; Pin 24 / TQFN)	Active-low asynchronous reset input	Resets all registers and I²C state machine without power cycle; minimum pulse width 25 ns.
A0, A1 (Pins 18, 2 / TSSOP; Pins 21, 23 / TQFN)	I²C slave address select inputs	Set fixed 7-bit address (11101xx) - enables up to four devices on same I²C bus.
SCL, SDA (Pins 22, 23 / TSSOP; Pins 19, 20 / TQFN)	I²C serial clock and open-drain data lines	Compliant with I²C electrical specs; includes internal noise filtering on both inputs.
IO0_0–IO0_7, IO1_0–IO1_7 (Pins 4–11, 13–20 / TSSOP; Pins 1–8, 10–17 / TQFN)	Configurable bidirectional I/O ports	Each pin independently set as input (high-Z) or output (push-pull); 5V tolerant regardless of VCC.

Key Features

Feature	Design Value
Individual I/O direction control	Two 8-bit Configuration registers allow per-pin input/output assignment - eliminates need for external direction logic.
Polarity inversion per I/O	Dual 8-bit Polarity registers enable software-inverted input reads - simplifies firmware handling of active-low sensors/switches.
Port-specific interrupt clearing	Reading Input Port 0 clears only Port 0 interrupts - prevents unintended masking of Port 1 events during polling.
Power-on reset with voltage threshold	Internal POR triggers at VPOR = 1.16–1.41 V - ensures deterministic initialization across supply ramp rates.
Noise-filtered I²C inputs	Integrated spike suppression (50 ns filter) on SCL/SDA - improves reliability in electrically noisy industrial environments.

Applications

ACPI Power Management

Industrial Push-Button Interface

Use Scenario: Monitoring chassis intrusion switches, lid-open sensors, and thermal shutdown flags in laptop/desktop platforms.

IC Role / Device Role / Timing Role: GPIO expander providing 16-bit parallel status capture with interrupt-driven wake-up signaling to EC or PCH.

Use Value: Reduces host processor polling overhead via edge-triggered INT; 5V tolerance accommodates legacy switch voltages.

Use Scenario: Reading mechanical push buttons and emergency stop inputs in PLC I/O modules and HMI panels.

IC Role / Device Role / Timing Role: Input concentrator with debounced sampling via I²C read + interrupt on change.

Use Value: Eliminates need for discrete RC filters or FPGA logic; 4 µs INT latency ensures sub-millisecond response.

LED Status Indication

Multi-Sensor Data Acquisition

Use Scenario: Driving 16 status LEDs (power, fault, comms, activity) in network switches and storage enclosures.

IC Role / Device Role / Timing Role: Constant-current-sink output driver with programmable on/off states via Output Port registers.

Use Value: 8–11 mA per I/O supports direct LED drive without external transistors; low ICC in standby extends battery life.

Use Scenario: Aggregating digital outputs from temperature, humidity, and motion sensors in smart building nodes.

IC Role / Device Role / Timing Role: Parallel-to-serial bridge converting 16 sensor status bits into I²C-accessible registers.

Use Value: Enables single I²C address to monitor multiple sensors; polarity inversion simplifies active-low sensor integration.

Equivalent & Alternatives

The following parts are listed as comparable options for similar GPIO expander applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
TCA6424A	3.3 V only supply (1.65–3.6 V); no 5V I/O tolerance; higher ICC (150 µA active)	Requires level shifting for 5 V sensors/switches; less suitable for mixed-voltage industrial designs	Select when system operates exclusively at 3.3 V and ultra-low active current is not required.
PCA9555	Slower max clock (400 kHz same, but weaker drive: 100 µA sink); no built-in noise filtering on SCL/SDA	Limited to low-noise environments; insufficient sink current for direct LED drive without external FETs	Choose only for cost-sensitive, low-speed, low-drive applications where ESD robustness is secondary.

Compared with TCA6424A and PCA9555, PI4IOE5V9539LE uniquely combines 2.3–5.5 V operation, 5V-tolerant I/Os, 8–11 mA sink capability, and integrated SCL/SDA noise filtering - making it optimal for ruggedized, mixed-voltage embedded control where reliability and direct peripheral drive matter.

Availability

PI4IOE5V9539LE is available at Aetrix Electronics and suitable for industrial automation controllers, server management subsystems, and smart home hubs requiring stable component supply, long-term lifecycle assurance, and dual-package flexibility.

Supply support for PI4IOE5V9539LE 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, energy-efficient components for industrial, computing, and consumer markets.

The PI4IOE5V9539 belongs to Diodes' I/O expansion portfolio, designed specifically for space-constrained embedded systems needing robust, low-power, mixed-voltage GPIO extension with interrupt-driven responsiveness.

FAQ

What is the function of the RESET pin, and does it require external pull-up?

The RESET pin is an active-low asynchronous input that forces all registers and the I²C state machine into their default power-on state without cycling VCC. It must be pulled up to VCC externally; driving it LOW for ≥25 ns initiates reset, and release to HIGH restores normal operation. Internal pull-up is not provided.

Can PI4IOE5V9539LE drive LEDs directly, and what is the maximum safe current per I/O?

Yes - each I/O can sink up to 11 mA (typical) at VOL ≤ 0.7 V, sufficient for standard indicator LEDs. However, total device sink current must not exceed 200 mA (100 mA per octal port), and individual I/O current must be externally limited to ≤25 mA to prevent damage per datasheet Section 3.

How does interrupt clearing work, and why might an interrupt persist after reading one port?

INT deasserts only when the Input Port register corresponding to the changed pin is read - e.g., a change on IO0_3 clears only after reading Input Port 0 (register 0). Reading Input Port 1 (register 1) has no effect on Port 0 interrupts, enabling precise event attribution in multi-port systems.

Is the I²C address configurable, and how many devices can share the same bus?

Yes - the 7-bit I²C address is fixed as 11101xx₂, where A0 and A1 pins determine the two LSBs. With A0/A1 tied to GND/VCC combinations, up to four PI4IOE5V9539LE devices can coexist on a single I²C bus without address conflict.

PI4IOE5V9539LE Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: 24-TSSOP (0.173", 4.40mm Width)

Packaging:: Tube

Product Status:: Active

Programmable:: Not Verified

Number of I/O:: 16

Interface:: I2C

Interrupt Output:: Yes

Features:: -

Output Type:: -

Current - Output Source/Sink:: -

Clock Frequency:: 400 kHz

Voltage - Supply:: 2.3V ~ 5.5V

Operating Temperature:: -40°C ~ 85°C

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 24-TSSOP

PI4IOE5V9539LE FAQ

1.How can I place an order for PI4IOE5V9539LE through Aetrix?

Please submit a Request for Quotation (RFQ) for PI4IOE5V9539LE 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 PI4IOE5V9539LE reliable?

The price and inventory of PI4IOE5V9539LE are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PI4IOE5V9539LE is usually 5 days.

3.What payment methods are accepted for PI4IOE5V9539LE?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PI4IOE5V9539LE transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for PI4IOE5V9539LE?

PI4IOE5V9539LE orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your PI4IOE5V9539LE 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 PI4IOE5V9539LE?

For technical support, including PI4IOE5V9539LE datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PI4IOE5V9539LE requirements.

6.How does Aetrix verify that PI4IOE5V9539LE is sourced from the original manufacturer or authorized distributors?

All PI4IOE5V9539LE 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 PI4IOE5V9539LE meets industry standards.

7.What is the process for return or replacement of PI4IOE5V9539LE?

All PI4IOE5V9539LE units undergo pre-shipment inspection (PSI). If there is an issue with PI4IOE5V9539LE, 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 PI4IOE5V9539LE part is unused and in its original packaging.

Return procedure for PI4IOE5V9539LE:

1.Submit a request within 90 days.

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

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