PIC18F4320-I/P Equivalent & Substitute Parts

Part Overview

The PIC18F4320-I/P is an 8-bit microcontroller from Microchip Technology's PIC® 18F series, currently in active production status. This device integrates 8KB of FLASH program memory, 512 bytes of RAM, and 256 bytes of EEPROM, operating at speeds up to 40MHz. The microcontroller features integrated communication interfaces (I2C, SPI, UART/USART), analog-to-digital conversion capability (13-channel 10-bit), and comprehensive peripheral support including brown-out detection, low-voltage detection, power-on reset, PWM, and watchdog timer functionality. The 40-pin DIP package provides 36 I/O lines for embedded system applications. Substitute parts are identified to address specific application requirements such as packaging preferences, inventory availability, or moisture sensitivity specifications while maintaining functional and electrical compatibility.

Substiute Parts

PIC18F4320-I/P

Microchip TechnologyIn Stock: 6389PIC18F4320-I/P Datasheet

Current PartRFQ

PIC18F4321-I/P

Microchip TechnologyIn Stock: 1440PIC18F4321-I/P Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PIC18F4320-I/P is based on strict equivalence of core electrical and functional parameters. The primary substitute identified is the PIC18F4321-I/P, which maintains identical specifications across all critical parameters that determine functional compatibility:

Core Equivalence Parameters:

• Identical 8-bit PIC core processor architecture
• Matching 40MHz maximum operating speed
• Equivalent 8KB FLASH program memory (4K x 16 organization)
• Identical 512 x 8 RAM and 256 x 8 EEPROM capacity
• Same 36 I/O line count
• Identical voltage supply range (4.2V ~ 5.5V)
• Matching 13-channel 10-bit analog-to-digital converter
• Equivalent communication interfaces (I2C, SPI, UART/USART)
• Same operating temperature range (-40°C ~ 85°C)
• Identical 40-DIP package and pinout

Differentiating Characteristics: The PIC18F4321-I/P differs in two non-functional attributes: packaging format (Tube versus standard) and moisture sensitivity level (MSL 1 with unlimited shelf life versus MSL 3 with 168-hour limitation). These differences do not affect electrical performance or circuit-level compatibility.

Parameter Comparison

Engineering Selection Recommendations

Both the PIC18F4320-I/P and PIC18F4321-I/P are active production devices from Microchip Technology with identical electrical specifications and functional capabilities. Selection between these parts is determined by non-functional factors:

PIC18F4320-I/P is appropriate for applications where standard packaging and handling procedures are acceptable, with moisture sensitivity level MSL 3 requiring storage within 168 hours of bag opening under controlled humidity conditions.

PIC18F4321-I/P is appropriate for applications requiring extended shelf life or storage in less controlled environments, as MSL 1 rating permits unlimited storage duration without moisture sensitivity constraints. This part is supplied in tube packaging format.

Both devices maintain full ROHS3 compliance and REACH unaffected status. Selection should be based on supply chain requirements, storage conditions, and packaging preferences rather than electrical performance, as functional equivalence is complete.

Frequently Asked Questions (FAQ)

Q: Are PIC18F4320-I/P and PIC18F4321-I/P pin-compatible?

A: Yes. Both devices use identical 40-DIP package with 0.600" (15.24mm) body dimensions and maintain identical pinout configurations. Direct socket substitution is possible without circuit modification.

Q: What is the difference between MSL 3 and MSL 1 moisture sensitivity ratings?

A: MSL 3 requires the device to be used within 168 hours of bag opening under controlled humidity conditions (typically 30% RH or less). MSL 1 has no time limitation and permits storage under standard conditions indefinitely. Selection depends on manufacturing environment and storage practices.

Q: Can I substitute PIC18F4321-I/P for PIC18F4320-I/P in existing designs?

A: Yes. Electrical and functional specifications are identical. No circuit design changes are required. Substitution is valid for new production or field replacement applications.

Q: Are there any firmware or software compatibility differences?

A: No. Both devices implement identical PIC 18F core architecture with matching instruction sets, memory organization, and peripheral configurations. Firmware compiled for one device executes identically on the other.

Q: What packaging formats are available?

A: PIC18F4320-I/P is supplied in standard packaging. PIC18F4321-I/P is supplied in tube packaging format. Both contain identical die and electrical specifications.

Q: Do both parts meet the same compliance standards?

A: Yes. Both devices are ROHS3 compliant and REACH unaffected. Export classification (ECCN 3A991A2) and tariff codes (HTSUS 8542.31.0001) are identical.