PIC17C43-16I/L Equivalent & Substitute Parts

Part Overview

The PIC17C43-16I/L is an 8-bit microcontroller from Microchip Technology's PIC® 17C series, featuring 8KB OTP program memory, 454 x 8 bytes of RAM, and 33 I/O pins in a 44-PLCC package. The device operates at 16MHz with a supply voltage range of 4.5V to 6V and includes integrated peripherals such as UART/USART connectivity, PWM, WDT, and POR functionality. This part is currently active in production and ROHS3 compliant.

Finding equivalent or substitute parts becomes necessary when the original part reaches end-of-life status, when inventory constraints occur, or when design requirements necessitate enhanced capabilities such as higher clock speeds, expanded memory, or improved peripheral integration. The PIC18F series offers modern alternatives with FLASH-based program memory and extended feature sets while maintaining core architectural compatibility.

Substiute Parts

PIC17C43-16I/L

Microchip TechnologyIn Stock: 1000328PIC17C43-16I/L Datasheet

Current PartRFQ

PIC18F4320-I/ML

Microchip TechnologyIn Stock: 2217PIC18F4320-I/ML Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PIC17C43-16I/L is evaluated based on the following critical parameters:

Core Architecture Compatibility: Both the main part and substitute must be PIC-based 8-bit microcontrollers to ensure instruction set compatibility and software portability.

Memory Configuration: Program memory size (8KB minimum) and RAM capacity (454 x 8 minimum) must be maintained or exceeded to support existing firmware without modification.

I/O Pin Count: A minimum of 33 I/O pins is required to preserve peripheral connectivity and signal routing in existing designs.

Operating Voltage Range: The substitute must operate within or encompass the 4.5V to 6V supply range to ensure compatibility with existing power distribution systems.

Package Compatibility: While the original uses a 44-LCC package, substitutes in alternative 44-pin packages (such as 44-QFN) are acceptable provided PCB layout and thermal management considerations are addressed during integration.

Temperature Range: The operating temperature range of -40°C to 85°C must be maintained or exceeded.

Compliance Status: Both parts must maintain ROHS3 compliance and active product status to ensure long-term availability and regulatory adherence.

The PIC18F4320-I/ML qualifies as a manufacturer-recommended substitute by meeting or exceeding all critical parameters while offering enhanced capabilities including FLASH-based reprogrammable memory, higher clock speed (40MHz), expanded I/O (36 pins), and integrated analog-to-digital conversion.

Parameter Comparison

Engineering Selection Recommendations

The PIC18F4320-I/ML is the manufacturer-recommended substitute for the PIC17C43-16I/L. Both devices maintain ROHS3 compliance and active product status, ensuring regulatory adherence and long-term supply chain stability.

The substitute provides equivalent program memory capacity (8KB) and exceeds RAM requirements (512 x 8 versus 454 x 8), supporting existing firmware without modification. The increased I/O count (36 versus 33 pins) and expanded peripheral set (I2C, SPI addition; Brown-out Detect/Reset, LVD addition) enable enhanced system functionality without architectural constraints.

The transition from OTP to FLASH-based program memory in the PIC18F4320-I/ML eliminates the one-time programmability limitation, allowing field updates and development iteration. The higher clock speed (40MHz versus 16MHz) provides performance headroom for computationally intensive applications.

Package transition from 44-LCC to 44-VQFN requires PCB layout redesign and thermal management evaluation. The exposed pad in the QFN package improves thermal dissipation compared to the LCC variant. Supply voltage range compatibility (4.2V to 5.5V for the substitute versus 4.5V to 6V for the original) requires verification against existing power supply specifications.

Frequently Asked Questions (FAQ)

Q: Can the PIC18F4320-I/ML directly replace the PIC17C43-16I/L without firmware changes?

A: The PIC18F4320-I/ML maintains equivalent program memory size (8KB) and exceeds RAM capacity, supporting existing firmware. However, instruction set differences between PIC17C and PIC18F architectures may require code review and potential recompilation. Peripheral register layouts and interrupt handling differ between series, necessitating driver-level validation.

Q: What are the package compatibility considerations?

A: The original PIC17C43-16I/L uses a 44-LCC (J-Lead) package, while the PIC18F4320-I/ML uses a 44-VQFN package. Both are 44-pin surface-mount packages but have different footprints, pin spacing, and thermal characteristics. PCB layout redesign is required for physical integration. The QFN package provides superior thermal performance through its exposed pad.

Q: Does the voltage supply range difference affect compatibility?

A: The PIC17C43-16I/L operates at 4.5V to 6V, while the PIC18F4320-I/ML operates at 4.2V to 5.5V. The substitute has a lower minimum voltage (4.2V) but a lower maximum voltage (5.5V). Existing power supplies delivering 4.5V to 5.5V are compatible with both devices. Systems requiring operation above 5.5V must retain the original part or implement voltage regulation.

Q: What advantages does FLASH memory provide over OTP?

A: FLASH-based program memory in the PIC18F4320-I/ML allows in-system reprogramming and field updates, eliminating the one-time programmability constraint of OTP. This enables firmware iteration, bug fixes, and feature updates without component replacement.

Q: Are the additional peripherals (I2C, SPI, A/D converter) backward compatible?

A: The PIC18F4320-I/ML includes I2C, SPI, and a 13-channel 10-bit analog-to-digital converter not present in the PIC17C43-16I/L. These peripherals are optional and do not interfere with existing UART/USART, PWM, or WDT functionality. Firmware can selectively enable or disable these features based on application requirements.

Q: What is the impact of the 40MHz clock speed versus 16MHz?

A: The PIC18F4320-I/ML operates at 40MHz compared to the 16MHz of the PIC17C43-16I/L, providing 2.5x performance improvement. Existing firmware will execute faster without modification. Timing-critical code (such as communication protocols or sensor sampling) may require adjustment to maintain intended timing characteristics.