PCA9557DT Texas Instruments Integrated Circuit (Small Outline Packages) In Stock
The PCA9557DT is an 8-bit I2C general-purpose I/O expander from Texas Instruments, featuring 8 bidirectional I/O lines accessible via I2C bus at up to 400 kHz clock. It provides 8-bit parallel I/O port expansion with one 8-bit port and is housed in a 16-pin SOIC package. This device is widely used in embedded systems to expand limited microcontroller I/O through a two-wire serial interface.
- Manufacturer
- Texas Instruments
- Package
- Small Outline Packages
- Pin Count
- 16
- Lifecycle
- OBSOLETE
- Datasheet
- PCA9557DT Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $0.9628(MOQ 1)
- Temp Range
- -40.0°C to 85.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 8-bit bidirectional I/O port expansion via I2C serial interface
- I2C bus operation up to 400 kHz for fast data transfer
- Single 8-bit port with 8 individually configurable I/O lines
- 3-pin address configuration for multiple devices on one bus
- 16-pin SOIC package for standard surface-mount applications
Applications
The PCA9557DT is used in microcontroller and single-board computer designs where additional GPIO lines are needed for controlling LEDs, relays, push buttons, or external peripherals via the I2C bus. It is commonly found in industrial HMI panels, home automation gateways, and embedded IoT devices requiring scalable I/O expansion without consuming additional MCU pins.
Specifications
| YTEOL | 0 |
| Address Bus Width | 8 |
| Clock Frequency-Max | 0.4MHz |
| JESD-30 Code | R-PDSO-G16 |
| JESD-609 Code | e4 |
| Number of Bits | 8 |
| Number of I/O Lines | 8 |
| Number of Ports | 1 |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SOP16,.25 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE |
| Peak Reflow Temperature (Cel) | 260 |
| Qualification Status | Not Qualified |
| Supply Current-Max | 0.025mA |
| Supply Voltage-Max | 5.5V |
| Supply Voltage-Min | 2.3V |
| Supply Voltage-Nom | 2.5V |
| Surface Mount | YES |
| Technology | CMOS |
| Temperature Grade | INDUSTRIAL |
| Terminal Finish | Nickel/Palladium/Gold (Ni/Pd/Au) |
| Terminal Form | GULL WING |
| Terminal Pitch | 1.27mm |
| Terminal Position | DUAL |
| Time@Peak Reflow Temperature-Max (s) | NOT SPECIFIED |
| uPs/uCs/Peripheral ICs Type | PARALLEL IO PORT, GENERAL PURPOSE |
| 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 | Malaysia |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for PCA9557DT:
Frequently Asked Questions
What interface does the PCA9557DT use?
The PCA9557DT uses the I2C two-wire serial interface operating at up to 400 kHz, allowing the host microcontroller to access all 8 GPIO lines using only two signal lines: SDA (data) and SCL (clock).
How many I/O lines does the PCA9557DT provide?
The PCA9557DT provides 8 bidirectional I/O lines in a single 8-bit port, each of which can be independently configured as an input or output for flexible peripheral interfacing.
Can multiple PCA9557DT devices be used on the same I2C bus?
Yes, the PCA9557DT supports 3-bit hardware address configuration, allowing up to 8 devices on a single I2C bus and enabling up to 64 additional GPIO lines per bus without any software conflicts.
What package is the PCA9557DT available in?
The PCA9557DT is available in a 16-pin SOIC (Small Outline IC) package, which is compatible with automated surface-mount PCB assembly and is suitable for both prototype and production designs.
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Why Buy from FindMyChip
About Texas Instruments
Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $3.4200 | $3.42 |
| 10+ | $1.3790 | $13.79 |
| 25+ | $1.2556 | $31.39 |
| 100+ | $1.1193 | $111.93 |
| 250+ | $1.0860 | $271.50 |
| 1000+ | $0.9628 | $962.80 |
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