PIC18C242-E/SP - 8-Bit PIC MCU, 16KB OTP, 28-Pin SPDIP | Microchip
MPN: PIC18C242-E/SP ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.92 | $8.92 |
| 10 | $8.03 | $80.30 |
| 100 | $6.45 | $645.00 |
| 500 | $5.1 | $2,550.00 |
| 1,000 | $4.25 | $4,250.00 |
PIC18C242-E/SP Overview
What is a PIC18C-series microcontroller? The PIC18C family is Microchip's OTP-programmed extension of the PIC18 architecture, providing 10 MIPS throughput (100 ns instruction execution), 77 single-word instructions, and source-code compatibility with the PIC16C5X, PIC12CXXX, PIC16CXX, and PIC17CXX device families. PIC18C devices integrate a high-performance RISC engine, peripherals such as 10-bit A/D converters, PWM modules, USART, and synchronous serial ports, making them a versatile 8-bit platform for embedded control designs that benefit from low unit cost and abundant peripheral integration.
Key features of the PIC18C242-E/SP include 16KB OTP program memory, 512 bytes of data RAM, a 10-bit analog-to-digital converter (ADC) module, a Universal Synchronous/Asynchronous Receiver-Transmitter (USART), an MSSP (Master Synchronous Serial Port) supporting SPI and I2C, capture/compare/PWM modules, and 23 I/O pins across four ports (PORTA-PORTC plus partial PORTD-equivalent functions on PORTC). The device executes instructions at 10 MIPS from a 40 MHz oscillator, providing ample headroom for real-time control loops.
Architecturally, the PIC18C242 uses a 16-bit instruction word with an 8-bit data path and a hardware multiplier, enabling efficient C code generation. The ADC module supports five input channels in the 28-pin package and integrates sample-and-hold, allowing direct interfacing with analog sensors without external signal conditioning.
Typical applications include industrial control modules, automotive body controllers, sensor signal conditioning, motor control low-end loops, appliance control boards, and general-purpose 8-bit embedded systems. The extended -40C to +125C temperature grade and OTP programmability make it particularly suited to high-volume automotive and industrial deployments.
When designing with this part, verify the OTP memory constraint: code is programmed once and cannot be erased, so production code must be fully validated on flash-equipped PIC18F siblings (e.g., PIC18F242) before final OTP programming. Decoupling capacitors (100 nF and 10 uF bulk) must be placed within 5 mm of the VDD/VSS pins, and the MCLR reset line should be pulled high through a 10 kohm resistor.
This page synthesizes distributor availability, parametric specifications, drop-in replacement candidates, and engineering design guidance not collated on any single distributor page.
Drop-in alternatives for PIC18C242-E/SP — 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 PIC18C242-E/SP (same form factor and footprint) — differing in Package, Core Architecture, Mounting Type, A/D Converter, Maximum CPU Speed.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F242-I/SP
✅ Drop-In✓ In Stock
$5.3 / Unit
View Datasheet →PIC18F242-E/SP
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18C242-I/SP
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$5.27 / Unit
View Datasheet →PIC18F2420-I/SP
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$5.22 / Unit
View Datasheet →PIC16LF873A-I/SP
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$5.78 / Unit
View Datasheet →PIC18C242-E/SP Maximum Ratings & Electrical Characteristics
| Device Family | PIC18C |
| Core Architecture | 8-bit PIC RISC |
| Program Memory Type | OTP (One-Time-Programmable EPROM) |
| Program Memory Size | 16 KB |
| RAM Size | 512 B |
| Maximum CPU Speed | 10 MIPS (40 MHz oscillator) |
| Instruction Execution Time | 100 ns (single-word instruction) |
| Instruction Set Size | 77 single-word instructions |
| I/O Pins | 23 |
| Supply Voltage (Vdd) | 5 V |
| Operating Temperature Range | -40C to +125C (Extended, "E" suffix) |
| A/D Converter | 10-bit, 5 channels (28-pin package) |
| Package | 28-pin SPDIP (Skinny Plastic DIP) - SP |
| Mounting Type | Through-Hole |
PIC18C242-E/SP Pin Configuration
| Pin 1 | MCLR — Master Clear (reset) input, internal pull-up |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input channel 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input channel 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / Analog input channel 2 |
| Pin 5 | RA3/AN3 — PORTA bit 3 / Analog input channel 3 |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4 — PORTA bit 5 / Analog input channel 4 |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKIN — Oscillator crystal input / external clock in |
| Pin 10 | OSC2/CLKOUT — Oscillator crystal output / clock out |
| Pin 11 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 12 | RC1/T1OSI — PORTC bit 1 / Timer1 oscillator input |
| Pin 13 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM1 |
| Pin 14 | RC3/SCK/SCL — PORTC bit 3 / SPI SCK / I2C SCL |
| Pin 15 | RC4/SDI/SDA — PORTC bit 4 / SPI SDI / I2C SDA |
| Pin 16 | RC5/SDO — PORTC bit 5 / SPI SDO |
| Pin 17 | RC6/TX/CK — PORTC bit 6 / USART TX / USART clock |
| Pin 18 | RC7/RX/DT — PORTC bit 7 / USART RX / USART data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply (5 V) |
| Pin 21 | RB0/INT0 — PORTB bit 0 / External interrupt 0 |
| Pin 22 | RB1/INT1 — PORTB bit 1 / External interrupt 1 |
| Pin 23 | RB2/INT2 — PORTB bit 2 / External interrupt 2 |
| Pin 24 | RB3/CCP2 — PORTB bit 3 / Capture-Compare-PWM2 |
| Pin 25 | RB4 — PORTB bit 4 |
| Pin 26 | RB5 — PORTB bit 5 |
| Pin 27 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 28 | RB7/PGD — PORTB bit 7 / ICSP data |
Typical Applications
PIC18C242-E/SP is suitable for 6 applications: Automotive Body Control Modules, Industrial Sensor Signal Conditioning, Appliance Control Boards, Low-Voltage Motor Control Loops, General 8-bit Embedded Control, Legacy Replacement and Field Service.
Automotive Body Control Modules
The PIC18C242-E/SP is well suited to automotive body controllers, BCMs, lighting controllers, and HVAC actuators where the extended -40C to +125C temperature grade is mandatory. Its 10 MIPS throughput, 16 KB OTP program memory, 512 B RAM, 10-bit ADC with five channels, and integrated USART enable direct connection to LIN transceivers, switch panels, and sensor networks. Compared to flash-only parts, OTP memory reduces per-unit cost in high-volume BCM deployments where firmware is fixed at production time.
Recommended
Industrial Sensor Signal Conditioning
In industrial sensor modules, the PIC18C242-E/SP's 10-bit ADC with five input channels and 512 B RAM makes it a practical choice for low-cost 4-20 mA loop transmitters, RTD signal conditioners, and pressure-sensor front ends. The 10 MIPS core runs PID compensation and linearization algorithms in real time, while the 23 I/O pins drive relay coils, status LEDs, and HMI displays. The extended temperature grade supports deployment in unconditioned control cabinets and outdoor enclosures.
Recommended
Appliance Control Boards
Washing machines, dishwashers, ovens, and HVAC indoor units benefit from the PIC18C242-E/SP's combination of PWM outputs, capture inputs, and USART for display panel interfacing. The 16 KB OTP program memory holds complete appliance state machines, while the 23 I/O pins drive triac controls, valve drivers, keypad matrices, and seven-segment displays without external logic. Cost-sensitive white-goods OEMs value OTP's per-unit price advantage when firmware is finalized for production.
Recommended
Low-Voltage Motor Control Loops
Small DC motors, stepper motors, and BLDC fans in 5V-class systems can be driven directly by the PIC18C242-E/SP through its PWM and CCP modules. The 10 MIPS throughput is sufficient for closed-loop velocity control using back-EMF sensing or Hall-effect feedback, and the 10-bit ADC monitors current via shunt resistors for protection. This compact 28-pin SPDIP part fits motor-control PCBs alongside gate drivers and power stages.
Recommended
General 8-bit Embedded Control
For general-purpose 8-bit designs such as access control keypads, electronic locks, smart metering, irrigation controllers, and consumer gadgets, the PIC18C242-E/SP provides a balanced combination of 16 KB OTP, 512 B RAM, USART, MSSP, ADC, PWM, and timer resources in a through-hole 28-pin SPDIP. Through-hole packaging simplifies prototyping and rework on hand-soldered or wave-soldered boards, making it attractive for low-volume and educational products.
Recommended
Legacy Replacement and Field Service
Because the PIC18C242-E/SP is now flagged NRND (Not Recommended for New Designs), its primary remaining use case is maintenance and replacement of installed equipment. The part is still stocked at distributors in tube packaging for repair depots, industrial service contracts, and end-of-life production runs where design re-validation costs outweigh the per-unit saving of switching to a successor. Engineers should evaluate PIC18F242-I/SP or PIC18F2420-I/SP as forward-compatible replacements with identical pin-out and code compatibility.
Recommended
Recommended Products Summary
Engineering reference data for PIC18C242-E/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F242-I/SP | PIC18F242-E/SP | PIC18C242-I/SP | PIC18F2420-I/SP | PIC16LF873A-I/SP |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin SPDIP | 28-pin SPDIP - same | 28-pin SPDIP - same | 28-pin SPDIP - same | 28-pin SPDIP - same | 28-pin SPDIP - same |
| Program Memory | 16 KB OTP | 16 KB Flash | 16 KB Flash | 16 KB OTP | 16 KB Flash | 7 KB Flash |
| RAM Size | 512 B | 512 B | 512 B | 512 B | 512 B | 192 B |
| Operating Temperature | -40C to +125C | -40C to +85C | -40C to +125C | -40C to +85C | -40C to +85C | -40C to +85C |
| I/O Pins | 23 | 23 | 23 | 23 | 23 | 22 |
| ADC | 10-bit, 5 ch | 10-bit, 5 ch | 10-bit, 5 ch | 10-bit, 5 ch | 10-bit, 5 ch (enhanced) | 10-bit, 5 ch |
| Core / Architecture | PIC18, 10 MIPS | PIC18, 10 MIPS | PIC18, 10 MIPS | PIC18, 10 MIPS | PIC18, 10 MIPS | PIC16, 5 MIPS |
| Lifecycle Status | NRND | Active | Active | NRND | Active | Active |
Key Differentiators
- Drop-in flash replacement available within same SPDIP-28 footprint (vs PIC18F242-I/SP)
- Extended -40C to +125C temperature grade unique to "E" suffix (vs PIC18C242-I/SP)
- Code-compatible migration path to PIC18F2420 with nanoWatt XLP (vs PIC18F2420-I/SP)
Design Notes
OTP memory constraint: the PIC18C242-E/SP's 16 KB OTP program memory can be written only once and cannot be electrically erased. Per the Microchip datasheet, prototypes and code-iteration cycles MUST be done on a flash-based equivalent (PIC18F242-I/SP or PIC18F2420-I/SP) before committing the final image to OTP parts. Burning incorrect code into OTP silicon permanently bricks the device.
Decoupling and reset: place a 100 nF ceramic decoupling capacitor within 5 mm of each VDD/VSS pair and a 10 uF bulk capacitor on the main supply rail. The MCLR pin (pin 1) must be pulled high through a 10 kohm resistor; do not leave MCLR floating. For noisy environments, add a 100 nF capacitor from MCLR to VSS to filter reset glitches.
Operating voltage and oscillator: the PIC18C242-E/SP is specified for 5 V (typical) operation. Per the datasheet, VDD must remain within the device's specified range for the chosen oscillator frequency. At 40 MHz, ensure VDD stays above the minimum specified for full-speed operation; do not assume operation at lower VDD without verifying against the datasheet DC characteristics table.
ADC noise mitigation: when sampling analog channels, route analog signals away from digital switching traces and avoid running ADC inputs parallel to high-frequency clock or PWM lines. Per Microchip layout guidelines, place the AVdd/Vdd bond close to a low-impedance ground plane and consider a small RC filter (1 kohm + 100 nF) on each analog input for high-impedance sensor sources.
Configuration bits and oscillator mode: the PIC18C242-E/SP's CONFIG word selects oscillator type (HS, XT, LP, RC), watchdog enable, brown-out voltage, and code protection. Per the datasheet, mis-setting CONFIG1L/CONFIG1H can prevent the device from running. Always double-check the configuration bits in MPLAB X IDE before generating production programming files.
Compliance Information
RoHS, REACH, and AEC-Q100 status not explicitly stated in the verified distributor snippets; consult the Microchip product page and Material Declaration sheets for authoritative compliance documentation. Microchip is a member of the Responsible Minerals Assurance Process (RMAP).
