My Inquiry
My Account
NXP Semiconductors PCA8574ATS,118
- Part No.:
- PCA8574ATS,118
- Manufacturer:
- NXP Semiconductors
- Category:
- I/O Expanders
- Package:
- 20-LSSOP (0.173", 4.40mm Width)
- Datasheet:
-
PCA8574ATS,118.pdf
- Description:
- IC XPNDR 400KHZ I2C 20SSOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,873
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
PCA8574ATS,118 from NXP Semiconductors is an 8-bit quasi-bidirectional I/O expander for I²C-bus (Fast-mode, 400 kHz), operating from 2.3 V to 5.5 V with 5.5 V-tolerant I/Os, featuring active-low open-drain interrupt output (INT), eight hardware-addressable slave addresses via A0–A2, and 25 mA per-pin sink capability for direct LED driving in industrial control and mobile device interfaces.
For engineers reviewing the PCA8574ATS,118 datasheet, PCA8574ATS,118 pinout, PCA8574ATS,118 application, or PCA8574ATS,118 equivalent, this device delivers remote GPIO expansion with low standby current (4.5 µA typical), power-on reset initialization to input mode, and interrupt-driven change detection-critical for keypad monitoring, LED signage, and embedded system resource offloading.
Technical Context
The PCA8574ATS,118 implements a single-register quasi-bidirectional I/O architecture where each of P0–P7 functions as input or output without direction register overhead; input state is sampled directly from pin voltage, while output HIGH relies on a 100 µA internal pull-up plus transient accelerator current during ACK cycle, and output LOW uses a strong n-channel sink transistor.
Its I²C interface supports Fast-mode (400 kHz) timing with standard START/STOP/ACK protocols; the INT pin asserts low on any input state transition and resets automatically upon read/write access or return to prior logic level-enabling efficient microcontroller event polling without bus contention.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| I²C Bus Speed | 400 kHz Fast-mode - enables high-throughput GPIO updates without requiring MCU clock stretching or custom timing firmware. |
| Supply Voltage Range | 2.3 V to 5.5 V - supports direct integration with 3.3 V and 5 V systems, with I/O pins tolerant to 5.5 V regardless of VDD level. |
| Quasi-Bidirectional I/O Count | 8 pins (P0–P7) - each independently configurable as input or output via single data byte, eliminating need for separate direction register or command overhead. |
| Interrupt Output | Active-low open-drain INT - signals input state changes to MCU without continuous polling; self-clearing on port read/write or state restoration. |
| Output Sink Capability | 25 mA per pin (min), 200 mA total package - sufficient to drive LEDs directly without external drivers, reducing BOM count and board space. |
| Standby Current | 4.5 µA typical - enables battery-powered operation in mobile and portable equipment with minimal quiescent drain. |
| Operating Temperature | −40 °C to +85 °C - qualified for industrial and automotive-adjacent environments including PLCs, medical devices, and server management subsystems. |
Pinout & Package
PCA8574ATS,118 is housed in SSOP20 (plastic shrink small outline package, 20 leads, 4.4 mm body width), with 4 no-connect (n.c.) pins and full pin compatibility across PCA8574/74A family variants in this package.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | INT | Active-low open-drain interrupt output - connects to MCU interrupt input; requires external pull-up; asserts when any input pin state differs from its register value. |
| 2 | SCL | Serial clock line - bidirectional I²C clock input synchronized to master; must be pulled up externally. |
| 4 | SDA | Serial data line - bidirectional I²C data path shared with other slaves; requires external pull-up. |
| 5 | VDD | Positive supply - powers internal logic and I/O circuitry; range 2.3 V to 5.5 V. |
| 6 | A0 | Slave address bit 0 - sets LSB of 7-bit I²C address; must be externally tied HIGH or LOW (no internal pull-up). |
| 7 | A1 | Slave address bit 1 - sets middle bit of 7-bit I²C address; externally biased for one of eight possible addresses. |
| 9 | A2 | Slave address bit 2 - sets MSB of fixed 7-bit address prefix (0x70–0x7F for PCA8574A); determines I²C bus address uniqueness. |
| 10–11, 14, 16–17, 19–20 | P0–P7 | Quasi-bidirectional I/O ports - default to inputs at power-up with 100 µA weak pull-up; sink up to 25 mA when driven LOW; tolerate 5.5 V when VDD ≤ 5.5 V. |
| 15 | VSS | Ground reference - common return for supply and I/O paths; must be low-impedance connection. |
| 3, 8, 13, 18 | n.c. | No-connect - internally unconnected; must remain floating or grounded per layout best practice (not tied to VDD/VSS). |
Key Features
| Feature | Design Value |
|---|---|
| Single-register I/O control | Eliminates direction register complexity-each port pin auto-adapts as input (reading external voltage) or output (driving LOW or weak HIGH) based on written data byte. |
| Hardware-configurable I²C address | Three address pins (A0–A2) enable eight unique slave addresses per device variant, supporting up to 16 expanders (128 I/Os) on one I²C bus. |
| Power-on reset (POR) | Internally initializes all I/Os as inputs with 100 µA pull-up to VDD-ensures safe default state before firmware configuration. |
| ESD and latch-up robustness | Exceeds 2000 V HBM and 1000 V CDM ESD ratings; latch-up immune per JEDEC JESD78 (>100 mA), suitable for harsh industrial handling. |
| LED-direct drive capability | 25 mA sink per pin and 200 mA total package limit allow direct connection of indicator LEDs with only series resistors-no external drivers needed. |
Applications
| Industrial Control Panels | LED Signage & Displays |
|---|---|
Use Scenario: Remote monitoring of pushbutton status and activation of status indicators on factory HMIs and programmable logic controller (PLC) I/O modules. IC Role / Device Role / Timing Role: I²C-based GPIO extender providing 8-bit parallel-to-serial conversion with interrupt-driven edge detection for real-time button press/release reporting. Use Value: Reduces MCU GPIO usage and eliminates polling overhead; INT signal triggers immediate firmware response to operator input without bus traffic during idle periods. |
Use Scenario: Driving multiple 7-segment digits or monochrome LED arrays in digital signage, kiosks, and point-of-sale terminals. IC Role / Device Role / Timing Role: Parallel output expander with 25 mA per-pin sink strength enabling direct LED cathode control using common-anode configurations. Use Value: Eliminates discrete transistor arrays or dedicated LED drivers; simplifies PCB layout and lowers component count while maintaining brightness consistency across segments. |
| Medical Equipment Interfaces | Mobile Device Keypads |
Use Scenario: Reading tactile switch matrices and controlling status LEDs in portable diagnostic tools and patient monitors operating under strict power budgets. IC Role / Device Role / Timing Role: Low-power (4.5 µA standby) I/O hub interfacing mechanical switches and visual indicators via I²C, synchronized to host processor interrupt events. Use Value: Extends battery life in handheld medical devices; interrupt-driven wake-up avoids constant I²C polling, preserving energy and reducing electromagnetic emissions. |
Use Scenario: Scanning membrane keypads and illuminating backlight zones in feature phones, ruggedized handhelds, and gaming peripherals. IC Role / Device Role / Timing Role: Quasi-bidirectional port expander configured with P0–P3 as inputs (key scan lines) and P4–P7 as outputs (backlight control), sharing single I²C address space. Use Value: Enables compact keypad subsystem design with minimal MCU pin usage; hardware address pins allow co-location of multiple expanders for larger key matrices. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar I²C I/O expander applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| PCA8574TS,118 | Same functionality and pinout but uses PCA8574 (not PCA8574A) slave address range (0x40–0x4F vs. 0x70–0x7F); identical SSOP20 package and electrical specs. | Requires I²C bus address reassignment in firmware; otherwise drop-in compatible in hardware and software for non-address-conflicted systems. | Select PCA8574TS,118 only if legacy PCF8574TS/3 migration or existing 0x40–0x4F address allocation is required. |
| PCA9674APW,118 | Higher I²C speed (1 MHz Fm+), 64 address options (vs. 8), same 25 mA sink and interrupt function; TSSOP16 package (16-pin) vs. SSOP20 (20-pin). | Not pin-compatible; requires PCB redesign; supports denser I²C networks and faster update rates for time-critical GPIO control. | Choose PCA9674APW,118 for new designs needing higher bandwidth, more address flexibility, or smaller footprint-accepting layout revision cost. |
Compared with PCA8574TS,118, the PCA8574ATS,118 offers guaranteed address separation in mixed PCA8574/PCA8574A systems; versus PCA9674APW,118, it trades speed and address count for pin compatibility with legacy PCF8574ATS/3 designs and simpler layout integration.
Availability
PCA8574ATS,118 is available at Aetrix Electronics and suitable for industrial control panels, LED signage systems, and medical equipment interfaces requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.
Supply support for PCA8574ATS,118 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
NXP Semiconductors is a global semiconductor company specializing in secure connectivity solutions for automotive, industrial, and IoT applications, with leadership in interface, power management, and embedded processing technologies.
The PCA8574/74A product line was designed to provide cost-effective, low-power I²C-based GPIO expansion for resource-constrained microcontrollers in industrial HMIs, consumer electronics, and portable instrumentation.
FAQ
What is the I²C slave address range for PCA8574ATS,118?
The PCA8574ATS,118 belongs to the PCA8574A variant and uses a fixed 7-bit slave address prefix of 0x70–0x7F (hex), determined by external biasing of A2–A0 pins. This differs from PCA8574 (0x40–0x4F) and allows up to 16 expanders (eight PCA8574 + eight PCA8574A) on one I²C bus without address conflict. The full address byte includes R/W bit.
Does PCA8574ATS,118 require external pull-up resistors on SDA and SCL lines?
Yes, PCA8574ATS,118 requires external pull-up resistors on both SDA and SCL lines to ensure proper I²C bus operation. The device does not include internal pull-ups on these lines; typical values range from 2.2 kΩ to 10 kΩ depending on bus capacitance and speed (400 kHz Fast-mode). Pull-ups connect to VDD (2.3–5.5 V).
How does the interrupt (INT) pin of PCA8574ATS,118 behave during power-on reset?
At power-on, PCA8574ATS,118 initializes all I/Os as inputs with 100 µA weak pull-up to VDD. If any port pin (e.g., P0) is externally pulled LOW, the INT pin asserts active-low immediately after POR release-signaling a state mismatch between pin voltage and register value. INT remains asserted until the port is read or written.
Can PCA8574ATS,118 drive LEDs directly without external transistors?
Yes, PCA8574ATS,118 can drive LEDs directly: each I/O pin sinks up to 25 mA (min) at VDD = 4.5 V, and the total package sink limit is 200 mA. For common-anode LED configurations, connect LED anodes to VDD and cathodes to P0–P7 through current-limiting resistors. Do not exceed per-pin or total limits simultaneously.
What is the maximum ambient temperature rating for PCA8574ATS,118?
The PCA8574ATS,118 is rated for operation from −40 °C to +85 °C ambient temperature, qualified per industrial specifications. Its thermal resistance (Rth(j-a)) is 136 °C/W in SSOP20 package, meaning junction temperature rise is predictable under defined power dissipation-critical for reliability in enclosed or high-temperature enclosures.
PCA8574ATS,118 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- NXP Semiconductors
- Series:
- -
- Package/Case:
- 20-LSSOP (0.173", 4.40mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Number of I/O:
- 8
- Interface:
- I2C
- Interrupt Output:
- Yes
- Features:
- POR
- Output Type:
- Push-Pull
- Current - Output Source/Sink:
- 100µA, 25mA
- 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:
- 20-SSOP
PCA8574ATS,118 FAQ
1.How can I place an order for PCA8574ATS,118 through Aetrix?
Please submit a Request for Quotation (RFQ) for PCA8574ATS,118 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 PCA8574ATS,118 reliable?
The price and inventory of PCA8574ATS,118 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PCA8574ATS,118 is usually 5 days.
3.What payment methods are accepted for PCA8574ATS,118?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PCA8574ATS,118 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for PCA8574ATS,118?
PCA8574ATS,118 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your PCA8574ATS,118 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 PCA8574ATS,118?
For technical support, including PCA8574ATS,118 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PCA8574ATS,118 requirements.
6.How does Aetrix verify that PCA8574ATS,118 is sourced from the original manufacturer or authorized distributors?
All PCA8574ATS,118 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 PCA8574ATS,118 meets industry standards.
7.What is the process for return or replacement of PCA8574ATS,118?
All PCA8574ATS,118 units undergo pre-shipment inspection (PSI). If there is an issue with PCA8574ATS,118, 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 PCA8574ATS,118 part is unused and in its original packaging.
Return procedure for PCA8574ATS,118:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
PCA8574ATS,118 Tags
-
TCA6408ARSVR
Texas Instruments
-
TCA9535RTWR
Texas Instruments
-
FXL6408UMX
onsemi
-
PCF8574ADWR
Texas Instruments
-
PCF8574APWR
Texas Instruments
-
TCA9555PWR
Texas Instruments
-
TCA9554PWR
Texas Instruments
-
TCA9554APWR
Texas Instruments
-
TCA9539PWR
Texas Instruments
-
TCA9534PWR
Texas Instruments
-
TCA9555RTWR
Texas Instruments
-
TCA9535PWR
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
