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NXP Semiconductors PCA9665PW,112

Name: PCA9665PW,112
Brand: NXP Semiconductors
SKU: PCA9665PW,112
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: PCA9665PW,112

Manufacturer:: NXP Semiconductors

Category:: Controllers

Package:: 20-TSSOP (0.173", 4.40mm Width)

Datasheet:: PCA9665PW,112.pdf

Description:: IC CNTRLR PARALLEL/I2C 20TSSOP

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Product details

Overview

PCA9665PW,112 from NXP Semiconductors is a parallel-bus–to–I²C-bus controller IC that bridges standard 8-bit parallel microcontrollers to the I²C-bus as master or slave, supporting Fast-mode Plus (Fm+) up to 1 MHz, 68-byte buffered data transfer, and 2.3 V–3.6 V operation with 5 V–tolerant I/Os. It enables bidirectional serial communication in industrial control panels requiring deterministic timing and multi-master arbitration.

For engineers reviewing the PCA9665PW,112 datasheet, PCA9665PW,112 pinout, PCA9665PW,112 application, or PCA9665PW,112 equivalent, this device delivers verified Fm+ protocol handling, software reset via parallel bus, internal oscillator (28.5 MHz), and interrupt-driven or polled handshake - critical for embedded systems integrating legacy parallel peripherals with modern I²C sensors and EEPROMs.

Technical Context

The PCA9665PW,112 implements full I²C-bus protocol logic-including START/STOP generation, arbitration resolution, ACK/NACK management, and clock stretching-without external timing components. Its dual-mode operation (Byte or Buffered) is controlled by the MODE bit in I2CCON, with Buffered mode enabling up to 68-byte transfers using the indirect register map and INDPTR pointer.

Internal register architecture separates four direct-access registers (I2CSTA, INDPTR, I2CDAT, I2CCON) from seven indirect registers (I2CCOUNT through I2CMODE), accessed via A1/A0 address decoding on the parallel bus. The ENSIO bit enables the SCL/SDA interface and activates the 28.5 MHz oscillator, which stabilizes within 550 µs.

Key Specifications

Parameter	Value and Actual Design Meaning
I²C Speed Mode	Fast-mode Plus (Fm+): supports 1 Mbit/s data rate with 25 mA SCL/SDA sink capability - enables high-throughput sensor networks without external bus buffers.
Supply Voltage	2.3 V to 3.6 V - compatible with 2.5 V and 3.3 V logic domains; 5 V–tolerant parallel I/Os allow direct interfacing with legacy 5 V microcontrollers.
Data Buffer	68-byte FIFO buffer - reduces CPU overhead in burst transfers (e.g., reading multi-byte ADC results or writing display frame buffers).
Internal Oscillator	28.5 MHz ±15 % - eliminates need for external crystal or RC network; startup time ≤550 µs after ENSIO assertion.
Operating Temperature	−40 °C to +85 °C - qualified for industrial environments including programmable logic controllers and motor drives.
I²C Addressing	7-bit slave address + General Call support (GC bit in I2CADR) - allows broadcast commands to multiple PCA9665PW,112 devices on same bus.
Interrupt Logic	Active-low open-drain INT output with SI flag in I2CCON - synchronizes CPU response to I²C state transitions (e.g., completion of byte transfer or arbitration loss).

Pinout & Package

TSSOP20 package (SOT360-1), 4.4 mm body width, 0.65 mm pitch, lead-free, RoHS-compliant. Thermal pad not present - no exposed center pad.

Pin/Terminal	Circuit Role	Design Meaning
D0–D7	Parallel data bus I/O	Bidirectional 3-state 8-bit interface to microcontroller data bus; D0 = LSB; requires CE/WR/RD handshaking for register access.
A0, A1	Register address select	Directly decode four register addresses (I2CSTA, INDPTR, I2CDAT, I2CCON); A1/A0 = 10 selects INDIRECT data field for indirect register access.
CE	Chip enable	Active-low enable for parallel bus transactions; places D0–D7 in high-impedance when deasserted - prevents bus contention during idle cycles.
WR, RD	Write/read strobes	Edge-triggered controls: WR rising edge latches data into addressed register; RD falling edge outputs register contents onto D0–D7.
INT	Interrupt request	Open-drain, active-low output signaling I²C state change (e.g., byte received, STOP detected); requires external pull-up to VDD or host rail.
RESET	Hardware reset	Active-low asynchronous reset clearing all registers and halting I²C state machine; debounced externally for noise immunity.
SCL, SDA	I²C-bus interface	Open-drain I²C lines supporting Fm+; require external pull-ups; 25 mA sink capability allows driving longer traces or multiple slaves.
VDD, VSS	Power supply	VDD = 2.3–3.6 V digital supply; VSS = ground reference; decoupling capacitor (100 nF) required within 5 mm of pins for stable oscillator operation.

Key Features

Feature	Design Value
Parallel-to-I²C protocol conversion	Full hardware implementation of I²C master/slave logic - offloads bit-banging from host CPU and guarantees strict compliance with I²C specification timing (tSU;STA, tHD;STA, etc.).
Multi-master arbitration	Automatic wired-AND arbitration resolution during simultaneous START conditions - ensures deterministic bus ownership without software intervention.
Software reset capability	Write to I2CPRESET (indirect address 05h) resets internal state machine and registers - enables recovery from bus lockup without cycling VDD or asserting hardware RESET.
General Call support	Configurable via GC bit in I2CADR - allows single broadcast command to initialize or configure multiple PCA9665PW,112 devices simultaneously on shared I²C bus.
ESD & latch-up robustness	≥2000 V HBM / ≥1000 V CDM ESD rating and >100 mA latch-up immunity per JEDEC JESD78 - ensures reliability in assembly and field-deployed industrial equipment.

Applications

Industrial PLC I/O Expansion	Automotive Body Control Module
Use Scenario: Adding isolated I²C sensor interfaces (temperature, humidity, position) to legacy parallel-based PLC backplanes without redesigning CPU bus interface. IC Role / Device Role / Timing Role: Parallel-bus–facing bridge IC translating 8-bit parallel commands into I²C START/STOP/data sequences; manages clock stretching during slow sensor responses. Use Value: Eliminates need for FPGA or custom ASIC; supports 1 MHz Fm+ for rapid polling of 16+ I²C nodes while maintaining <10 µs interrupt latency to host CPU.	Use Scenario: Integrating I²C-connected door lock actuators, mirror position sensors, and ambient light detectors into a centralized BCM using existing 8-bit microcontroller with no native I²C peripheral. IC Role / Device Role / Timing Role: I²C master controller managing concurrent read/write operations across multiple slave devices; handles arbitration during simultaneous window lift and seat position updates. Use Value: Enables deterministic 2 ms cycle time for safety-critical functions via buffered mode transfers; 5 V–tolerant D0–D7 pins interface directly to 5 V MCU without level shifters.
Medical Patient Monitor Data Hub	Smart Energy Meter Communication Gateway
Use Scenario: Aggregating data from I²C-based ECG front-end, SpO₂ sensor, and temperature probe into a parallel-bus ARM9 host processor running real-time OS. IC Role / Device Role / Timing Role: Buffered-mode I²C slave/master hybrid - acts as slave to host CPU for command reception and master to sensors for synchronized multi-byte reads. Use Value: 68-byte buffer prevents CPU starvation during burst acquisition; internal oscillator eliminates crystal BOM cost and layout area in space-constrained PCBs.	Use Scenario: Connecting I²C EEPROM (calibration data), RTC, and metrology ADC to a parallel-bus–based metering SoC in DIN-rail energy meters operating at −25 °C to +70 °C. IC Role / Device Role / Timing Role: Robust I²C master with timeout protection (I2CTO register) - recovers autonomously from SCL-stuck faults caused by EMI or faulty slave devices. Use Value: Prevents system hang during power-line transients; −40 °C to +85 °C rating ensures long-term stability in outdoor meter enclosures with solar heating.

Industrial PLC I/O Expansion

Automotive Body Control Module

Use Scenario: Adding isolated I²C sensor interfaces (temperature, humidity, position) to legacy parallel-based PLC backplanes without redesigning CPU bus interface.

IC Role / Device Role / Timing Role: Parallel-bus–facing bridge IC translating 8-bit parallel commands into I²C START/STOP/data sequences; manages clock stretching during slow sensor responses.

Use Value: Eliminates need for FPGA or custom ASIC; supports 1 MHz Fm+ for rapid polling of 16+ I²C nodes while maintaining <10 µs interrupt latency to host CPU.

Use Scenario: Integrating I²C-connected door lock actuators, mirror position sensors, and ambient light detectors into a centralized BCM using existing 8-bit microcontroller with no native I²C peripheral.

IC Role / Device Role / Timing Role: I²C master controller managing concurrent read/write operations across multiple slave devices; handles arbitration during simultaneous window lift and seat position updates.

Use Value: Enables deterministic 2 ms cycle time for safety-critical functions via buffered mode transfers; 5 V–tolerant D0–D7 pins interface directly to 5 V MCU without level shifters.

Medical Patient Monitor Data Hub

Smart Energy Meter Communication Gateway

Use Scenario: Aggregating data from I²C-based ECG front-end, SpO₂ sensor, and temperature probe into a parallel-bus ARM9 host processor running real-time OS.

IC Role / Device Role / Timing Role: Buffered-mode I²C slave/master hybrid - acts as slave to host CPU for command reception and master to sensors for synchronized multi-byte reads.

Use Value: 68-byte buffer prevents CPU starvation during burst acquisition; internal oscillator eliminates crystal BOM cost and layout area in space-constrained PCBs.

Use Scenario: Connecting I²C EEPROM (calibration data), RTC, and metrology ADC to a parallel-bus–based metering SoC in DIN-rail energy meters operating at −25 °C to +70 °C.

IC Role / Device Role / Timing Role: Robust I²C master with timeout protection (I2CTO register) - recovers autonomously from SCL-stuck faults caused by EMI or faulty slave devices.

Use Value: Prevents system hang during power-line transients; −40 °C to +85 °C rating ensures long-term stability in outdoor meter enclosures with solar heating.

Equivalent & Alternatives

The following parts are listed as comparable options for similar parallel-to-I²C bridge applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
PCA9665APW,118	PCA9665A variant with 32 MHz oscillator (vs. 28.5 MHz), 'glitch-free' restart logic, and TSSOP20-only packaging - identical pinout and register map.	Preferred where restart reliability under noisy conditions is critical (e.g., motor drive gate drivers sharing same PCB); supports same Fm+ timing but tighter oscillator tolerance.	Select PCA9665APW,118 if restart integrity in electrically harsh environments outweighs minor cost premium over PCA9665PW,112.
PCA9564PW,118	Legacy predecessor: supports only Standard/Fast-mode (400 kbit/s), 32-byte buffer, no General Call or software reset; shares SO20/TSSOP20 footprint but lacks Fm+ drive strength.	Suitable for low-speed, cost-sensitive designs where 1 MHz bandwidth and 68-byte buffering are unnecessary - e.g., simple EEPROM configuration reads.	Choose PCA9564PW,118 only for backward compatibility or where Fm+ features are unused; not drop-in for PCA9665PW,112 due to missing registers and reduced drive.

Compared with PCA9564PW,118, the PCA9665PW,112 adds 150 % higher I²C throughput, doubles buffer depth, and introduces software-initiated recovery - making it essential for real-time sensor fusion. Versus PCA9665APW,118, it trades restart robustness for lower oscillator power and broader legacy compatibility.

Availability

PCA9665PW,112 is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, medical monitoring, and smart metering applications requiring stable component supply, long-lifecycle assurance, and RoHS-compliant sourcing.

Supply support for PCA9665PW,112 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 leader specializing in secure connectivity solutions for automotive, industrial, and IoT applications, with core expertise in interface, power management, and microcontroller technologies.

The PCA9665PW,112 belongs to NXP's I²C-bus controller product line, engineered specifically to extend parallel-bus microcontrollers into modern sensor-rich, multi-node I²C ecosystems - emphasizing interoperability, noise immunity, and minimal firmware overhead.

FAQ

What is the maximum I²C data rate supported by the PCA9665PW,112?

The PCA9665PW,112 supports Fast-mode Plus (Fm+) operation up to 1 Mbit/s. This is achieved via 25 mA sink capability on SCL and SDA pins, enabling reliable signaling on buses with higher capacitance or longer trace lengths. The internal oscillator (28.5 MHz) and programmable SCL LOW/HIGH period registers (I2CSCLL/I2CSCLH) allow precise timing calibration to meet Fm+ specifications under varying load conditions. PCA9665PW,112 achieves this without external timing components.

Does the PCA9665PW,112 require an external crystal or RC oscillator?

No, the PCA9665PW,112 integrates a trimmed internal oscillator operating at 28.5 MHz ±15 %, eliminating the need for external timing components. Startup completes within 550 µs after setting the ENSIO bit in the I2CCON register. This simplifies BOM, reduces PCB area, and improves reliability in vibration-prone or thermally cycling environments where crystals may drift or fail. PCA9665PW,112 uses this oscillator exclusively for all I²C timing generation.

How does the PCA9665PW,112 handle I²C bus arbitration in multi-master systems?

The PCA9665PW,112 implements hardware-based wired-AND arbitration per the I²C specification. When multiple masters initiate START simultaneously, the device monitors SDA during the address phase and automatically relinquishes bus control if it detects a mismatch between its transmitted address bit and the bus level. No firmware intervention is needed - the PCA9665PW,112 exits transmission, sets appropriate status bits (e.g., arbitration lost in I2CSTA), and asserts INT to notify the host CPU. PCA9665PW,112 resumes operation only after detecting a STOP condition.

Can the PCA9665PW,112 operate with a 5 V microcontroller parallel bus?

Yes, the PCA9665PW,112 features 5 V–tolerant parallel I/O pins (D0–D7, A0, A1, CE, WR, RD, INT, RESET), allowing direct connection to 5 V microcontrollers without level-shifting circuitry. Its core logic operates from 2.3 V–3.6 V (VDD), so only the parallel interface is 5 V–capable - SCL/SDA remain 3.3 V–domain I²C signals. This dual-voltage design makes PCA9665PW,112 ideal for upgrading legacy 5 V systems to I²C without redesigning the host MCU interface.

What is the function of the INDPTR register in the PCA9665PW,112?

INDPTR (Indirect Pointer register) is an 8-bit write-only direct register (A1=0, A0=0) that selects which of the seven indirect-addressed registers (e.g., I2CCOUNT, I2CADR, I2CSCLL) will be accessed next via the INDIRECT data field (A1=1, A0=0). Writing a value (00h–06h) to INDPTR configures subsequent reads/writes to the corresponding indirect register. This two-step addressing enables compact register mapping while keeping the parallel bus interface minimal. PCA9665PW,112 relies on INDPTR to configure clock timing, slave addressing, and buffer behavior.

PCA9665PW,112 Specifications

Product attributes: Attribute value

Manufacturer:: NXP Semiconductors

Package/Case:: 20-TSSOP (0.173", 4.40mm Width)

Programmable:: Not Verified

Protocol:: I2C

Function:: Controller

Interface:: Parallel

Standards:: -

Voltage - Supply:: 2.3V ~ 3.6V

Current - Supply:: 100µA

Operating Temperature:: -40°C ~ 85°C

Supplier Device Package:: 20-TSSOP

Grade:: -

Qualification:: -

PCA9665PW,112 FAQ

1.How can I place an order for PCA9665PW,112 through Aetrix?

Please submit a Request for Quotation (RFQ) for PCA9665PW,112 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 PCA9665PW,112 reliable?

The price and inventory of PCA9665PW,112 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PCA9665PW,112 is usually 5 days.

3.What payment methods are accepted for PCA9665PW,112?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PCA9665PW,112 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for PCA9665PW,112?

PCA9665PW,112 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your PCA9665PW,112 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 PCA9665PW,112?

For technical support, including PCA9665PW,112 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PCA9665PW,112 requirements.

6.How does Aetrix verify that PCA9665PW,112 is sourced from the original manufacturer or authorized distributors?

All PCA9665PW,112 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 PCA9665PW,112 meets industry standards.

7.What is the process for return or replacement of PCA9665PW,112?

All PCA9665PW,112 units undergo pre-shipment inspection (PSI). If there is an issue with PCA9665PW,112, 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 PCA9665PW,112 part is unused and in its original packaging.

Return procedure for PCA9665PW,112:

1.Submit a request within 90 days.

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

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