PIC18C252/JW - 8-Bit 40MHz 32KB EPROM 28-CerDip MCU | Microchip
MPN: PIC18C252/JW ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.5 | $14.50 |
| 10 | $12.95 | $129.50 |
| 100 | $11.2 | $1,120.00 |
| 500 | $9.85 | $4,925.00 |
| 1,000 | $8.75 | $8,750.00 |
PIC18C252/JW Overview
An 8-bit microcontroller (MCU) is a single-chip computer built around a CPU core, program memory, data RAM, and integrated peripherals such as timers, ADC, communication ports, and I/O. PIC18-family MCUs belong to Microchip's enhanced mid-range 8-bit RISC architecture, which sits hierarchically between the legacy PIC16 mid-range and the PIC17 high-end series, and forms the foundation of Microchip's PIC architecture (micros, microcontrollers, semiconductors, integrated circuits). The /JW suffix denotes a windowed ceramic package that allows UV erasure of the EPROM array for repeated development cycles - a hallmark of legacy OTP-based PIC18C devices.
Key features include a C-compiler-optimized RISC architecture with only 77 single-word instructions, source-code compatibility with PIC16CXX devices, a hardware single-cycle 8x8 multiplier, eight-level priority interrupt controller, and dual 16-bit Capture/Compare/PWM modules. The 28-pin windowed CerDIP is rated for the commercial 0C to +70C range and supports 23 digital I/O lines for user application interfaces.
Typical applications include embedded control prototypes, industrial automation controllers, instrumentation front-ends, motor control loops, and educational development platforms where UV-erasable program memory accelerates firmware iteration. The windowed package is also preferred for low-volume production runs and field firmware updates via UV erasure.
When designing with this part, verify that in-circuit socketing accommodates the 0.600-inch wide CerDIP body and the quartz window. Migration to the pin-compatible flash-based PIC18F252 is recommended for new designs because OTP/EPROM devices are NRND - the silicon is mature and Microchip explicitly recommends PIC18F252 as the modern replacement.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the standalone manufacturer datasheet.
Drop-in alternatives for PIC18C252/JW — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with PIC18C252/JW (same form factor and footprint) — differing in Mounting Type, ADC, Core Architecture, Operating Temperature, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F252-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F252-I/JW
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18C252-I/SP
✅ Drop-In✓ In Stock
$5.45 / Unit
View Datasheet →PIC18C252-E/SP
✅ Drop-In✓ In Stock
$4.6 / Unit
View Datasheet →PIC18F252-I/SO
✅ Drop-In✓ In Stock
$3.95 / Unit
View Datasheet →PIC18C252/JW Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit) |
| Program Memory Type | EPROM (UV-erasable, windowed) |
| Program Memory Size | 32 KB (16K x 16) |
| RAM Size | 1.5 KB (1536 bytes) |
| Maximum CPU Frequency | 40 MHz |
| Instruction Throughput | 10 MIPS |
| Instruction Cycle Time | 100 ns |
| Number of I/O Pins | 23 |
| Package Type | 28-pin Windowed Ceramic DIP (CerDIP), 0.300 inch / 7.62 mm row spacing |
| Mounting Type | Through-Hole |
| Operating Voltage | 4.2 V to 5.5 V (5 V nominal) |
| Operating Temperature Range | 0C to +70C (commercial) |
| Number of Instructions | 77 single-word |
| Multiplier | Single-cycle 8x8 hardware |
| Interrupt Priority Levels | 8 |
| On-chip Peripherals | Brown-out Reset, LVD, POR, PWM, WDT, Capture/Compare |
| MSL Level | N/A (through-hole, not moisture-sensitive) |
PIC18C252/JW Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input / Programming voltage input |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / Analog input 2 |
| Pin 5 | RA3/AN3/VREF — PORTA bit 3 / Analog input 3 / Voltage reference |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / Analog input 4 / SPI slave select |
| Pin 8 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 9 | OSC2/CLKOUT — Oscillator crystal output / clock output |
| Pin 10 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 11 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 |
| Pin 12 | RC2/CCP1 — PORTC bit 2 / Capture Compare PWM 1 |
| Pin 13 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 14 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 15 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 16 | RC6/TX/CK — PORTC bit 6 / USART transmit / USART clock |
| Pin 17 | RC7/RX/DT — PORTC bit 7 / USART receive / USART data |
| Pin 18 | RB0/INT0 — PORTB bit 0 / External interrupt 0 |
| Pin 19 | RB1/INT1 — PORTB bit 1 / External interrupt 1 |
| Pin 20 | VSS — Ground reference |
| Pin 21 | VDD — Positive supply voltage (+5V) |
| Pin 22 | RB2 — PORTB bit 2 |
| Pin 23 | RB3 — PORTB bit 3 |
| Pin 24 | RB4 — PORTB bit 4 |
| Pin 25 | RB5 — PORTB bit 5 |
| Pin 26 | RB6/PGC — PORTB bit 6 / In-circuit debugger clock |
| Pin 27 | RB7/PGD — PORTB bit 7 / In-circuit debugger data |
| Pin 28 | VSS — Ground reference (secondary) |
Typical Applications
PIC18C252/JW is suitable for 6 applications: Embedded Control Prototyping, Industrial Automation Controllers, Instrumentation Front-Ends, Motor Control Loops, Educational Development Platforms, Low-Volume Production Controllers.
Embedded Control Prototyping
The PIC18C252/JW's 32 KB UV-erasable EPROM and 40 MHz / 10 MIPS throughput make it ideal for embedded control prototyping where firmware must be revised repeatedly during development. Per the Microchip datasheet DS39526, the windowed /JW ceramic package permits dozens of UV erase cycles, accelerating the bring-up loop for closed-loop controllers. The 1.5 KB RAM comfortably holds stack plus buffers for UART, ADC, and PWM control variables. Engineers typically pair this MCU with an external EPROM eraser socket and use the 23 I/O pins to drive sensors, H-bridges, and indicator LEDs.
Recommended
Industrial Automation Controllers
The PIC18C252/JW fits industrial automation controllers because its integrated peripherals - PWM, Capture/Compare, WDT, BOR, LVD - handle motor drive signaling and sensor feedback without external driver ICs. According to the Microchip datasheet, the 8-level priority interrupt controller supports deterministic response times for safety-critical interlocks. The 40 MHz CPU cycle (100 ns instruction) enables real-time PID loops at typical 1 kHz control rates. The 0C to +70C commercial temperature rating suits cabinet-mounted equipment, while the -I/SP variants extend coverage for harsher factory environments.
Recommended
Instrumentation Front-Ends
The PIC18C252/JW is well-suited for instrumentation front-ends where 10 MIPS throughput drives ADC sampling, FFT preprocessing, and LCD update tasks. Per Microchip datasheet DS39526, the 16-bit instruction bus and 8x8 hardware multiplier accelerate numerical conditioning of sensor signals. The 23 I/O pins can simultaneously drive a character LCD, keypad matrix, UART telemetry, and SPI peripherals such as external ADCs or DACs. The windowed EPROM allows iterative tuning of calibration coefficients stored in firmware during prototype characterization.
Recommended
Motor Control Loops
The PIC18C252/JW's dual 16-bit Capture/Compare/PWM modules and 40 MHz instruction rate make it capable of running brushed DC and stepper motor control loops at typical 20 kHz PWM frequencies. According to the Microchip datasheet, the 8-level interrupt priority allows deterministic current-sense sampling and commutation timing. The 32 KB program memory accommodates state-machine commutation tables plus velocity-profile lookup tables. Windowed EPROM is particularly valuable during development when motor tuning parameters are iterated frequently.
Recommended
Educational Development Platforms
The PIC18C252/JW is widely used in university embedded systems courses because the windowed ceramic package allows students to erase and reprogram their own firmware using a low-cost UV eraser, reinforcing memory technology concepts. Per Microchip datasheet DS39526, the 77-instruction PIC18 RISC set provides a manageable learning curve while supporting real C-compiler development via MPLAB XC8. The 28-pin DIP footprint fits standard breadboards and ZIF sockets used in academic labs. Pin-compatible migration to PIC18F252 lets instructors teach both legacy EPROM and modern flash paradigms.
Recommended
Low-Volume Production Controllers
The PIC18C252/JW suits low-volume production controllers and field-firmware-updatable systems because the windowed EPROM allows field re-programming without a dedicated programmer - field engineers can update firmware using a portable UV eraser and standard device programmer. According to Microchip datasheet DS39526, the 28-pin CerDIP package has a documented long-term reliability track record in industrial and military applications. The 5V supply tolerance simplifies integration with legacy analog signal conditioning circuits. For larger volumes, Microchip recommends transitioning to PIC18F252 in-circuit flash variants.
Recommended
Recommended Products Summary
Engineering reference data for PIC18C252/JW — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F252-I/SP | PIC18F252-I/JW | PIC18C252-I/SP | PIC18C252-E/SP | PIC18F252-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin Windowed CerDIP | 28-pin SPDIP - same footprint | 28-pin Windowed CerDIP - same | 28-pin SPDIP - same footprint | 28-pin SPDIP - same footprint | 28-pin SOIC - PCB redesign required |
| Program Memory Type | 32 KB UV-EPROM | 32 KB flash | 32 KB flash | 32 KB OTP EPROM | 32 KB OTP EPROM | 32 KB flash |
| Maximum Frequency | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| RAM Size | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB |
| Operating Temperature | 0C to +70C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +125C | -40C to +85C |
| Lifecycle Status | NRND | Active | Active | NRND | NRND | Active |
| Reprogrammability | UV erasure via window | In-circuit flash, 100k cycles | In-circuit flash, 100k cycles | OTP, not erasable | OTP, not erasable | In-circuit flash, 100k cycles |
| I/O Pins | 23 | 23 | 23 | 23 | 23 | 23 |
Key Differentiators
- UV-erasable windowed ceramic package for prototype development cycles (vs PIC18F252-I/SP)
- Legacy Microchip PIC18C architecture with proven long-term reliability (vs PIC18F252-I/JW)
- Single 5V supply operation matches legacy industrial designs (vs PIC18F252-I/SO)
Design Notes
The PIC18C252/JW operates from a single 5V supply at 4.2V to 5.5V per the Microchip datasheet DS39526. Decouple VDD with a 100 nF ceramic capacitor placed within 5 mm of the VDD pin and a bulk 10 uF tantalum or aluminum polymer capacitor at the PCB power entry. Add a ferrite bead or small inductor (10 uH) on the VDD trace if the board shares a noisy switching regulator. Brown-out Reset (BOR) is enabled by configuration fuse and will hold the MCU in reset until VDD rises above the BOR threshold (~4.0V typical), preventing code execution at marginal voltages.
Estimated: At maximum 40 MHz operation from a 5V supply with all peripherals active, the PIC18C252/JW draws approximately 25-35 mA, dissipating 125-175 mW. The 28-pin CerDIP has a theta_JA of approximately 60 C/W, yielding a junction temperature rise of 7.5-10.5 C above ambient - well within the 0C to +70C commercial range. No heatsink is required. For long-term reliability in enclosed housings, ensure ambient temperature stays below 60 C and provide minimum 1 oz copper pour on VDD/GND planes for heat spreading.
The 28-pin CerDIP body is 0.600 inch wide (larger than 0.300 inch for SOIC). PCB sockets must accept this wider footprint - use machined-pin DIP sockets (e.g., 3M 28-pin socket) for production, or zero-insertion-force (ZIF) sockets for development with UV erasure cycles. Place the quartz erase window unobstructed (no heat sinks or components above it) to allow UV eraser access. Route OSC1/OSC2 traces short and symmetric to minimize parasitic capacitance; ground guard the oscillator traces to reduce EMI coupling.
Do not confuse the /JW windowed CerDIP with the -I/SP plastic SPDIP - they are electrically identical but only the /JW allows UV erasure. When migrating to PIC18F252, verify configuration bits: PIC18F252 flash erase/write cycles (1,000 minimum, 100,000 typical) and BOR/POR thresholds differ slightly from PIC18C252 EPROM part. The PIC18C252 has no in-circuit serial programming (ICSP) capability; programming must use a high-voltage parallel programmer that drives VPP (pin 1) to 13V. For new designs, switch to PIC18F252 for ICSP support.
The PIC18C252/JW operates at 40 MHz internal clock with 100 ns instruction cycle; signal integrity for I/O switching should account for 10 ns rise/fall times. Place 33 ohm series resistors on PORTB and PORTC outputs driving long PCB traces (>50 mm) to dampen ringing. The CCP1/CCP2 PWM outputs (RC2/RC1) can switch up to 20 mA - if driving external MOSFET gates directly, add 100 ohm gate resistors to limit peak current. The MCLR pin (pin 1) requires a 10 kohm pull-up to VDD and a 100 nF decoupling cap to ground for noise immunity.
Compliance Information
RoHS and REACH compliance status not explicitly stated in verified web data for PIC18C252/JW; the windowed CerDIP package was originally designed before RoHS directives. AEC-Q100 is not applicable - this is a commercial-grade MCU without automotive qualification. Engineers should verify compliance with Microchip directly for new product designs.
