PIC18C252-E/SO - 32KB OTP 8-bit MCU, 10 MIPS, 28-SOIC | Microchip
MPN: PIC18C252-E/SO ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.5 | $12.50 |
| 10 | $11.2 | $112.00 |
| 100 | $9.85 | $985.00 |
| 500 | $8.6 | $4,300.00 |
| 1,000 | $7.4 | $7,400.00 |
PIC18C252-E/SO Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory, data RAM, peripherals, and I/O on a single die. Within the PIC architecture hierarchy, the PIC18C family is the OTP-based, 5V legacy branch, sitting alongside the PIC16 mid-range and PIC17 high-performance lines, and is itself upward compatible with PIC16C5X, PIC12CXXX, PIC16CXX, and PIC17CXX devices, providing a seamless migration path to the flash-based PIC18F generation.
The PIC18C252 features a Harvard RISC architecture with 77 single-word instructions, 16-bit wide instructions, an 8-bit wide data path, a single-cycle hardware 8x8 multiplier, and a linear data memory space of up to 4 KB. Peripherals include a 10-bit ADC with up to 5 channels, two Capture/Compare/PWM (CCP) modules, USART, MSSP (SPI/I2C), 22 digital I/O pins, and two 8-bit / three 16-bit timers, with separate priority levels for interrupts and an 8x8 hardware multiply that executes in one cycle.
Performance is anchored by a 40 MHz maximum external oscillator (DC to 40 MHz primary; 4 MHz to 10 MHz when the PLL is active), giving the 10 MIPS throughput and 100 ns instruction cycle time. The CMOS process and OTP program memory target cost-sensitive high-volume embedded designs where flash reprogramming is not required and the extended -40C to +125C operating range is mandatory.
Typical applications include industrial control nodes, automotive body and instrument cluster subsystems, motor-control signal conditioning, sensor interfacing, and legacy PIC16/17 system upgrades that need extra program memory or I/O. New designs should evaluate the recommended Microchip PIC18F252 successor for flash-based reprogrammability, in-circuit debugging, and longer product lifecycle support.
When laying out the PCB, place decoupling capacitors (typically 0.1 uF) within 5 mm of VDD/VSS, route MCLR through the recommended RC network with a dioded pull-up, and respect the 28-pin SOIC land pattern exactly - the -E/SO extended-temperature SOIC footprint is the same as the -I/SO industrial part, allowing PCB reuse.
Drop-in alternatives for PIC18C252-E/SO — 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-E/SO (same form factor and footprint) — differing in ADC, Operating Temperature, Package, Timers, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F252-I/SO
✅ Drop-In✓ In Stock
$3.95 / Unit
View Datasheet →PIC18C252-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18C252-E/SP
✅ Drop-In✓ In Stock
$4.6 / Unit
View Datasheet →PIC18C452-E/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F252-E/SO
✅ Drop-In✓ In Stock
$5.78 / Unit
View Datasheet →PIC18C252-E/SO Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit RISC Microcontroller (MCU) |
| Architecture | PIC18C (OTP, Harvard, 5 V) |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 32 KB (16K x 16) |
| RAM Size | 1.5 KB x 8 |
| Data EEPROM | 256 bytes x 8 (per datasheet family) |
| Instruction Set | 77 single-word instructions, 16-bit wide |
| CPU Throughput | 10 MIPS (100 ns instruction cycle) |
| Maximum Clock Frequency | 40 MHz (DC-40 MHz osc / 4-10 MHz with PLL) |
| Number of I/O Pins | 22 |
| ADC | 10-bit, multi-channel |
| Timers | Two 8-bit and three 16-bit timers |
| CCP Modules | 2 (Capture / Compare / PWM) |
| Serial Interfaces | USART (SCI) + MSSP (SPI / I2C) |
| Hardware Multiplier | 8 x 8 single-cycle |
| Operating Voltage | 4.2 V to 5.5 V (5 V typical) |
| Operating Temperature | -40C to +125C (Extended, -E) |
| Package | 28-SOIC (0.295 in / 7.50 mm body width) |
| Mounting Type | Surface Mount |
| Packaging | Tube |
PIC18C252-E/SO Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear (reset) input / programming high voltage / digital I/O |
| Pin 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Pin 4 | RA2/AN2/VREF- — PORTA bit 2 / analog input 2 / ADC negative reference |
| Pin 5 | RA3/AN3/VREF+ — PORTA bit 3 / analog input 3 / ADC positive 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/CLKI — Crystal oscillator input / external clock input |
| Pin 9 | OSC2/CLKO — Crystal oscillator output / clock output |
| Pin 10 | RB0/INT0 — PORTB bit 0 / external interrupt 0 |
| Pin 11 | VSS — Ground reference |
| Pin 12 | RB1/INT1 — PORTB bit 1 / external interrupt 1 |
| Pin 13 | RB2/INT2 — PORTB bit 2 / external interrupt 2 |
| Pin 14 | RB3/CCP2 — PORTB bit 3 / CCP2 alternate pin |
| Pin 15 | RB4 — PORTB bit 4 |
| Pin 16 | RB5 — PORTB bit 5 |
| Pin 17 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 18 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 19 | VSS — Ground reference (secondary) |
| Pin 20 | VDD — Positive supply (5 V typical) |
| Pin 21 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 22 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 |
| Pin 23 | RC2/CCP1 — PORTC bit 2 / CCP1 |
| Pin 24 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 25 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 26 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 27 | RC6/TX/CK — PORTC bit 6 / USART TX / USART clock |
| Pin 28 | RC7/RX/DT — PORTC bit 7 / USART RX / USART data |
Typical Applications
PIC18C252-E/SO is suitable for 6 applications: Industrial Control Nodes, Automotive Body Electronics, Sensor Signal Conditioning, Motor Control / PWM Driver, Legacy PIC16/PIC17 System Upgrade, HMI Keypad / Display Interface.
Industrial Control Nodes
The PIC18C252-E/SO's 10 MIPS CPU, 32 KB OTP program memory, and -40C to +125C extended temperature grade make it well suited for industrial control nodes such as PLC I/O modules, sensor signal conditioners, and simple machine controllers. Its 22 digital I/O pins drive relays, opto-isolators, and HMI keypads; the 10-bit ADC reads 4-20 mA transducer signals with adequate resolution for setpoint control; and the two CCP modules generate PWM outputs for valve and motor speed regulation. The OTP memory prevents firmware theft in deployed equipment and the SOIC package handles factory-floor thermal stress. Unlike the PIC18F successor, OTP enforces final BOM lock-in once programmed.
Recommended
Automotive Body Electronics
The -40C to +125C extended temperature range and 5 V supply tolerance of the PIC18C252-E/SO fit automotive body-electronics modules such as door-lock controllers, seat-position memories, climate-panel slave nodes, and lighting drivers. The 10 MIPS throughput handles LIN-style protocol stacks and PWM dimming; two CCP modules drive MOSFET bridges for window lift and mirror actuators; the 10-bit ADC reads thermistor and potentiometer wiper voltages with sufficient accuracy for HVAC control. Note that the part is not AEC-Q100 qualified, so it is best deployed in non-safety-critical body nodes where extended temperature is the dominant qualification.
Recommended
Sensor Signal Conditioning
The PIC18C252-E/SO integrates a 10-bit multi-channel ADC with on-chip reference, two CCP modules, and a 10 MIPS core - exactly what sensor-signal-conditioning front-ends need. Strain-gauge bridges, RTDs, thermocouples, and pressure transducers feed the ADC through external instrumentation amplifiers; the MCU then linearizes, filters, and reports the value over USART (RS-232/RS-485) or SPI. The 1.5 KB of RAM is sufficient for moving-average and Kalman-style filters, and the single-cycle 8x8 hardware multiplier accelerates scaling math. The extended -40C to +125C range allows deployment in outdoor and under-hood environments.
Recommended
Motor Control / PWM Driver
The PIC18C252-E/SO delivers two independent CCP/PWM channels and three 16-bit timers, which is the minimum hardware complement for sensored brushless-DC motor commutation and brushed-DC PWM speed control. The 10 MIPS throughput executes field-oriented-control loops for low-RPM torque management, while the 22 I/O pins handle Hall-sensor inputs, brake/coast signals, and fault inputs from current-sense comparators. Pair the MCU with external gate drivers such as the MCP8024 or IRS2003 for a complete 3-phase inverter. The SOIC package dissipates moderate MOSFET-gate-drive switching losses comfortably in sealed enclosures.
Recommended
Legacy PIC16/PIC17 System Upgrade
The PIC18C252-E/SO is upward compatible with the PIC16C5X, PIC12CXXX, PIC16CXX, and PIC17CXX instruction sets, making it a drop-in upgrade target for legacy designs that need more program memory (32 KB vs typical 2-8 KB), more RAM (1.5 KB), and higher throughput (10 MIPS vs 5 MIPS) without rewriting the entire firmware in assembly. Migrating from a 28-pin PIC16C7X design requires only a recompile and re-pin-out verification. For new projects in this segment, designers should evaluate the PIC18F252-I/SO flash-based successor, which adds in-circuit debugging and modern peripherals while keeping the same SOIC footprint.
Recommended
HMI Keypad / Display Interface
The PIC18C252-E/SO's 22 I/O pins, two CCP/PWM channels, and USART make it a natural fit for low-cost HMI keypads, character-LCD interfaces, and seven-segment display multiplexers. The MCU scans up to 8x8 matrix keypads using Timer0 interrupts, multiplexes 4- to 16-digit LED displays via the 16-bit timers, and reports state changes over RS-232 to a host controller. The 32 KB OTP holds full state-machine firmware and lookup tables, while the 1.5 KB RAM provides ample buffer for debounced key queues. The extended temperature range supports outdoor kiosks and industrial panel-mount HMIs.
Recommended
Recommended Products Summary
Engineering reference data for PIC18C252-E/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F252-I/SO | PIC18C252-I/SO | PIC18C252-E/SP | PIC18C452-E/SO | PIC18F252-E/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (7.50 mm) | 28-SOIC - same | 28-SOIC - same | 28-SPDIP - through-hole | 28-SOIC - same (40-pin die) | 28-SOIC - same |
| Program Memory | 32 KB OTP | 32 KB Flash | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB Flash |
| RAM | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB |
| CPU Throughput | 10 MIPS @ 40 MHz | 10 MIPS @ 40 MHz | 10 MIPS @ 40 MHz | 10 MIPS @ 40 MHz | 10 MIPS @ 40 MHz | 10 MIPS @ 40 MHz |
| Operating Voltage | 4.2 V to 5.5 V | 2.0 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 2.0 V to 5.5 V |
| Operating Temperature | -40C to +125C (E) | -40C to +85C (I) | -40C to +85C (I) | -40C to +125C (E) | -40C to +125C (E) | -40C to +125C (E) |
| Lifecycle Status | Obsolete | Active | Obsolete | Obsolete | Obsolete | Active |
| I/O Pins | 22 | 22 | 22 | 22 | 33 | 22 |
| ADC | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit |
| In-Circuit Debug | No | Yes (ICD2) | No | No | No | Yes (ICD2) |
| Unit Price @ qty 1 (USD) | 12.50 | 8.20 | 10.80 | 11.60 | 13.90 | 9.40 |
Key Differentiators
- Extended temperature grade -40C to +125C (vs PIC18C252-I/SO)
- Manufacturer-recommended flash-based successor (vs PIC18C252 family (all variants))
- Surface-mount SOIC vs through-hole SPDIP (vs PIC18C252-E/SP)
Design Notes
PIC18C252-E/SO operates from 4.2 V to 5.5 V with a 5 V typical supply. Place a 0.1 uF decoupling capacitor within 5 mm of each VDD/VSS pair (pins 20/11 and 20/19), and add a bulk 10 uF tantalum or ceramic capacitor at the regulator output. The AVDD and AVSS pins (shared with VDD/VSS on 28-pin parts) should be filtered with a ferrite bead or 10 ohm resistor plus 0.1 uF/10 uF capacitor network to isolate ADC reference noise from digital switching. Power-on ramp must meet datasheet parameter D003 (Vdd rise time) - use a supervisor such as MCP100 if the regulator ramp is slow.
Layout the 28-SOIC (7.50 mm body) footprint exactly to JEDEC MS-013 - 1.27 mm pitch, 0.41 mm pad width, 0.64 mm pad length. Route MCLR (pin 1) with the recommended RC network (typically 10 kohm pull-up to VDD, 100 nF to ground) and a clamping diode (e.g., BAV99) to VDD to suppress ESD. Keep the ICSP pins (RB6/PGC pin 17, RB7/PGD pin 18) accessible for OTP programming. Route the crystal traces (OSC1/OSC2, pins 8-9) as short as possible and guard them with a ground pour to minimize EMI pickup.
Because PIC18C252-E/SO uses OTP EPROM, every firmware revision requires a new chip - there is no flash reprogramming. Plan firmware stability carefully and use windowed CERDIP prototypes (PIC18C252-I/SP or PIC18C252/JW equivalents) for development. The CCP2 pin is multiplexed between RB3 (pin 14) and RC1 (pin 22) via the CCP2MX fuse - verify which pin carries CCP2 in your firmware before laying out external PWM driver circuits. Finally, the -E extended grade is rated -40C to +125C but is not AEC-Q100 qualified - do not use it in safety-critical automotive applications.
At 40 MHz oscillator frequency the 10 MIPS core generates sharp switching transients on the digital I/O pins. Use series 22-33 ohm damping resistors on long MCU-HCK-12 signal traces to the connector or peripheral ICs, and provide a solid unbroken ground plane beneath the MCU. The analog inputs (RA0-RA5) should be routed away from digital switching lines, with a guard ground trace between analog and digital sections of the PCB to preserve ADC accuracy. If the application uses the ADC at full 40 MHz oscillator, configure the ADC acquisition time (ADCON1/ADCON2) appropriately for the source impedance.
Compliance Information
RoHS/REACH status not explicitly stated in the verified distributor data - see Microchip product page for confirmation. Not AEC-Q100 qualified despite -40C to +125C temperature range, so do not deploy in automotive safety-critical applications. Lead-free per Microchip packaging standard. Conflict-minerals declaration compliant per Microchip policy.
