MCP23017T-E/SS Microchip Integrated Circuit (Small Outline Packages) In Stock

The MCP23017T-E/SS is a 16-bit I2C GPIO expander from Microchip with two 8-bit ports, 10 MHz clock support, and interrupt output pins, packaged in a 28-pin SSOP for easy PCB integration when microcontroller GPIO pins are insufficient.

ACTIVEIntegrated CircuitVerified Jun 2026
Package / Visual Reference
MCP23017T-E/SSSmall Outline Packages
Quick Facts
Manufacturer
Microchip
Package
Small Outline Packages
Pin Count
28
Lifecycle
ACTIVE
Category
Integrated Circuit
Price
From $1.2631(MOQ 1)
Temp Range
-40.0°C to 125.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

Key Features

  • 16 I/O lines organized as two independent 8-bit ports (PORTA/PORTB) with individual direction control registers
  • I2C interface operating up to 400 kHz (fast mode) with 10 MHz maximum clock for high-speed polling applications
  • Hardware interrupt outputs (INTA/INTB) for event-driven designs that reduce CPU polling overhead
  • Programmable pull-up resistors on all 16 I/O pins eliminate the need for external pull-up components
  • Wide supply voltage range of 1.8 V to 5.5 V compatible with modern 3.3 V and legacy 5 V microcontroller systems

Applications

The MCP23017T-E/SS is used extensively in embedded systems where microcontroller GPIO resources are exhausted, such as keyboard matrix scanning, LED panel driving, and relay control boards. Its I2C interface allows up to 8 MCP23017 devices to share a single 2-wire bus, expanding a system to 128 additional I/O lines with minimal wiring. The interrupt output pins enable reactive designs in industrial control panels, home automation gateways, and robotics controllers where pin-change detection reduces CPU load.

Specifications

Pbfree CodeYes
Manufacturer Package CodeSSOP-28
Factory Lead Time2Weeks
YTEOL8
Clock Frequency-Max10MHz
JESD-30 CodeR-PDSO-G28
JESD-609 Codee3
Number of Bits16
Number of I/O Lines16
Number of Ports2
Package Body MaterialPLASTIC/EPOXY
Package Equivalence CodeSSOP20,.3
Package ShapeRECTANGULAR
Package StyleSMALL OUTLINE, SHRINK PITCH
Peak Reflow Temperature (Cel)260
Qualification StatusNot Qualified
Supply Current-Max1mA
Supply Voltage-Max5.5V
Supply Voltage-Min4.5V
Supply Voltage-Nom5V
Surface MountYES
TechnologyCMOS
Temperature GradeAUTOMOTIVE
Terminal FinishMatte Tin (Sn)
Terminal FormGULL WING
Terminal Pitch0.65mm
Terminal PositionDUAL
uPs/uCs/Peripheral ICs TypePARALLEL IO PORT, GENERAL PURPOSE
## MCP23017T-E/SS Alternates Showing resultsImage
PackageSmall Outline Packages

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
Moisture Sensitivity LevelMSL 1
ECCNEAR99
HTS Code8542.39.00.01
Country of OriginPhilippines, Thailand

Datasheet

MCP23017T-E/SS Datasheet Download

Official datasheet from Microchip

Alternate & Equivalent Parts

Compatible alternatives and drop-in replacements for MCP23017T-E/SS:

MCP23018-E/SSMicrochip Technology Inc

Parallel I/O Port, 16-Bit, 16 I/O, CMOS, PDSO24

View Part →

Frequently Asked Questions

How many GPIO pins does the MCP23017T-E/SS add to a microcontroller, and how are they organized?

The MCP23017T-E/SS provides 16 additional GPIO pins split into two independent 8-bit ports (PORTA and PORTB), each with its own direction, pull-up, and interrupt configuration registers. This doubles the available I/O on a typical 16-pin microcontroller without adding extra address lines.

How many MCP23017T-E/SS devices can share a single I2C bus, and what address range do they use?

Up to 8 MCP23017T-E/SS devices can share a single I2C bus using 3 hardware address pins (A0, A1, A2), yielding 128 additional I/O lines from one 2-wire bus. The I2C base address is 0x20, with addresses 0x20 through 0x27 available depending on the A0-A2 pin states.

Does the MCP23017T-E/SS support interrupt-driven I/O, and how does this reduce CPU overhead?

Yes, the MCP23017T-E/SS has two dedicated interrupt output pins (INTA for PORTA, INTB for PORTB) that assert when any enabled pin changes state. This allows a host microcontroller to sleep between events rather than polling at 400 kHz, reducing active CPU time by orders of magnitude in low-power IoT and battery-operated designs.

What supply voltage does the MCP23017T-E/SS require, and is it 3.3 V and 5 V compatible?

The MCP23017T-E/SS operates from 1.8 V to 5.5 V, making it compatible with 3.3 V ARM Cortex-M microcontrollers, 5 V AVR systems, and single-cell LiPo battery supplies. No level-shifting is required when interfacing with 3.3 V logic that drives I2C bus lines through standard open-drain topology.

For a relay driver board with 16 outputs, is the MCP23017T-E/SS a suitable I/O expander choice?

The MCP23017T-E/SS is a strong fit for 16-channel relay driver boards because each of its 16 I/O pins can sink up to 25 mA and source 25 mA, sufficient to drive opto-isolator inputs directly. Paired with a ULN2803 darlington array, all 16 relay coils up to 500 mA each can be controlled from a single I2C address on a 3.3 V or 5 V bus.

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AvailabilityIn Stock
Reference Price (USD)
From $1.2631
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
1+$1.6900$1.69
2+$1.2631$2.53
pcs
Unit price: $1.6900 · Total: $1.69

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Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

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