PIC18C442-I/P Equivalent & Substitute Parts

Part Overview

The PIC18C442-I/P is an 8-bit microcontroller from Microchip Technology's PIC® 18C series, featuring 16KB OTP program memory and a 40-pin PDIP package. This device is classified as obsolete, making substitute parts necessary for new designs and production continuity. The PIC18C442-I/P operates at 40MHz with integrated peripherals including PWM, watchdog timer, and analog-to-digital conversion capabilities, serving embedded control applications requiring through-hole mounting.

Substiute Parts

PIC18C442-I/P

Microchip TechnologyIn Stock: 3175PIC18C442-I/P Datasheet

Current PartRFQ

PIC18F4420-I/P

Microchip TechnologyIn Stock: 2471PIC18F4420-I/P Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PIC18C442-I/P is determined by the following critical parameters:

Electrical Compatibility:

• Core processor architecture (PIC family)
• Core size (8-Bit)
• Operating frequency (40MHz)
• Supply voltage range (4.2V ~ 5.5V)
• Program memory capacity (16KB minimum)
• Connectivity interfaces (I2C, SPI, UART/USART)

Physical Compatibility:

• Mounting type (Through Hole)
• Package type (40-DIP)
• Package dimensions (0.600", 15.24mm)

Functional Compatibility:

• Peripheral set (PWM, WDT, Brown-out Detect/Reset, POR)
• I/O pin count (minimum 33)

The PIC18F4420-I/P qualifies as a substitute based on matching all critical electrical and physical parameters while offering enhanced capabilities in program memory type (FLASH vs. OTP), EEPROM availability, and expanded I/O count.

Parameter Comparison

Engineering Selection Recommendations

The PIC18F4420-I/P is the qualified substitute for the obsolete PIC18C442-I/P. Both devices maintain identical core electrical specifications (8-bit architecture, 40MHz operation, 4.2V–5.5V supply range) and physical form factor (40-DIP through-hole package).

The PIC18F4420-I/P offers production advantages over the original part:

Product Status: The PIC18F4420-I/P maintains active product status with ongoing manufacturer support and availability, whereas the PIC18C442-I/P is obsolete.

Compliance: Both parts are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements.

Memory Technology: The transition from OTP to FLASH program memory in the substitute enables field reprogramming and development flexibility without requiring new silicon for firmware updates.

Enhanced Capabilities: The substitute provides increased RAM (768 x 8 vs. 512 x 8), integrated EEPROM (256 x 8), expanded I/O count (36 vs. 33), and higher-resolution analog conversion (13x10b vs. 8x10b), all within the same package footprint and supply voltage range.

Frequently Asked Questions (FAQ)

Q: Can the PIC18F4420-I/P directly replace the PIC18C442-I/P in existing designs?

A: Yes. Both devices share identical pinout, package dimensions, supply voltage range, and core operating frequency. The 40-DIP through-hole package and pin assignments are compatible. Firmware compatibility depends on application-specific code; the FLASH memory type of the substitute allows for code updates without hardware changes.

Q: What are the key differences between these two parts?

A: The primary differences are program memory type (OTP vs. FLASH), available RAM (512 x 8 vs. 768 x 8), EEPROM presence (none vs. 256 x 8), I/O pin count (33 vs. 36), and analog converter resolution (8x10b vs. 13x10b). Both maintain identical speed, supply voltage, and package specifications.

Q: Why is the PIC18C442-I/P obsolete?

A: The PIC18C442-I/P has been discontinued by Microchip Technology. The PIC18F4420-I/P represents the active product line continuation with enhanced features and ongoing manufacturer support.

Q: Are there any compatibility concerns with the 40-DIP package?

A: No. Both parts use identical 40-DIP (0.600", 15.24mm) through-hole packaging. PCB layouts, socket compatibility, and mechanical mounting are fully interchangeable.

Q: Does the substitute require different oscillator configuration?

A: The PIC18C442-I/P requires external oscillator configuration, while the PIC18F4420-I/P supports internal oscillator operation. Designs using external oscillators with the original part will function with the substitute; internal oscillator capability in the substitute provides additional design flexibility.

Q: What is the impact of increased I/O count (36 vs. 33)?

A: The substitute provides three additional I/O pins. Existing designs using 33 I/O pins will function without modification. The additional pins enable expanded functionality in new designs without requiring a larger package.