MCP23S18-E/SO Microchip Integrated Circuit (Small Outline Packages) In Stock
Microchip MCP23S18-E/SO is a 16-bit SPI I/O expander in SOIC-28 package with 10 MHz bus speed, 2 independently configurable 8-bit ports, and interrupt outputs. Available from stock with worldwide shipping.
- Manufacturer
- Microchip
- Package
- Small Outline Packages
- Pin Count
- 28
- Lifecycle
- ACTIVE
- Datasheet
- MCP23S18-E/SO Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $1.5400(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 bidirectional I/O lines split across 2 independently configurable 8-bit ports for flexible pin assignment
- SPI interface at up to 10 MHz enabling fast bulk GPIO register updates in high-throughput control systems
- Hardware interrupt outputs per port allowing event-driven GPIO monitoring without polling overhead
Applications
The MCP23S18-E/SO is ideal for expanding the GPIO count of microcontrollers in industrial panel controllers, keyboard matrix interfaces, and relay driver boards where SPI is preferred over I2C for speed and noise immunity. Its dual 8-bit port architecture allows separate configuration of input and output banks with independent interrupt lines. The SOIC-28 package makes it compatible with standard PCB assembly and easy to evaluate on breadboard adapters during prototyping.
Specifications
| Manufacturer Package Code | SOIC-28 |
| Factory Lead Time | 2Weeks |
| YTEOL | 9 |
| Clock Frequency-Max | 10MHz |
| JESD-30 Code | R-PDSO-G28 |
| JESD-609 Code | e3 |
| Number of Bits | 16 |
| Number of I/O Lines | 16 |
| Number of Ports | 2 |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SOP28,.4 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE |
| Peak Reflow Temperature (Cel) | 260 |
| Qualification Status | Not Qualified |
| Supply Current-Max | 1mA |
| Supply Voltage-Max | 5.5V |
| Supply Voltage-Min | 1.8V |
| Supply Voltage-Nom | 5V |
| Surface Mount | YES |
| Technology | CMOS |
| Temperature Grade | AUTOMOTIVE |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | GULL WING |
| Terminal Pitch | 1.27mm |
| Terminal Position | DUAL |
| uPs/uCs/Peripheral ICs Type | PARALLEL IO PORT, GENERAL PURPOSE |
| ## MCP23S18-E/SO Alternates Showing results | Image |
| Package | Small Outline Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.01 |
| Country of Origin | Thailand |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for MCP23S18-E/SO:
suggested
suggested
suggested
suggested
Frequently Asked Questions
How fast can the MCP23S18-E/SO SPI bus operate and how does that affect GPIO update latency?
The MCP23S18-E/SO supports an SPI clock up to 10 MHz. At that rate, a full 16-bit GPIO port state update takes approximately 3.2 µs including SPI framing, which is fast enough for relay drivers, LED matrices, and keypad scan tasks in systems where total scan cycle time must remain below 1 ms.
How many I/O lines does the MCP23S18-E/SO provide and how are they organized?
The device provides 16 bidirectional I/O lines organized as two 8-bit ports (PORTA and PORTB), each independently configurable for direction, pull-up, polarity, and interrupt-on-change, giving designers fine-grained control over mixed input/output configurations without affecting the other port.
When would a designer choose the SPI-based MCP23S18 over the I2C-based MCP23018 for a GPIO expansion task?
The SPI MCP23S18-E/SO is preferred when the host MCU already uses SPI for other peripherals (saving a bus), when bus speed above 400 kHz is needed for low-latency keypad or encoder scanning, or in electrically noisy environments where SPI's push-pull signaling outperforms I2C open-drain lines over long PCB traces beyond 20 cm.
What is the lead time for the MCP23S18-E/SO and what stocking strategy suits mid-volume production?
Factory lead time is approximately 2 weeks, which is short by semiconductor standards. For mid-volume production runs of 500 to 5000 units, a safety stock of 4 to 6 weeks of consumption is reasonable to absorb any spot shortages without risking line stoppage.
Related Guides
How to Choose a 3528 SMD Indicator LED for Blue Status Lighting: Selection Guide
A practical 3528 SMD indicator LED selection guide using 150141BS73100 and related Wurth 150141 variants for blue status lighting.
Jul 5, 2026
BAS70KFILM Design Guide for Low-Leakage Signal Clamping and RF Detector Inputs
Practical BAS70KFILM design guidance for signal clamps, RF detector inputs, leakage control, capacitance, layout, and sourcing alternatives.
Jul 5, 2026
How to Choose a BAS70 Schottky Diode for Signal Clamping: Selection Guide
A practical BAS70KFILM and BAS70-family Schottky diode selection guide for signal clamping, RF detection, leakage, and topology choices.
Jul 4, 2026
AMC1202DWVR Design Guide for Isolated Current Sensing
Practical AMC1202DWVR design guide covering shunt sizing, isolation layout, input filtering, ADC scaling, and sourcing choices.
Jul 4, 2026
Why Buy from FindMyChip
About Microchip
Microchip is a leading electronic component manufacturer. FindMyChip sources Microchip ICs directly from authorized China distributors, offering competitive pricing and reliable stock.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $1.5846 | $1.58 |
| 400+ | $1.5800 | $632.00 |
| 1000+ | $1.5700 | $1570.00 |
| 1250+ | $1.5400 | $1925.00 |
In Stock · 24h Response · Worldwide Shipping
Response within 24 hours · Worldwide shipping
“We've been using FindMyChip for 2 years. Pricing is consistently 20-30% below Mouser/DigiKey for volume orders.”