PIC17C42A-16E/P - 8-Bit OTP MCU, 4KB, 16MHz, 40-DIP | Microchip
MPN: PIC17C42A-16E/P ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.8 | $9.80 |
| 10 | $8.75 | $87.50 |
| 100 | $7.4 | $740.00 |
| 500 | $6.55 | $3,275.00 |
| 1,000 | $5.85 | $5,850.00 |
PIC17C42A-16E/P Overview
An 8-bit microcontroller is a single-chip computer that combines a CPU, program memory, data memory, and peripherals on one die; the PIC17C family is Microchip's high-performance branch of the 8-bit portfolio, sitting above the PIC16C/PIC12C lines and below the PIC18C. OTP (One-Time Programmable) means the program memory can be written once and is non-volatile thereafter - ideal for low-cost production runs where firmware is finalized at assembly.
Key features include 16 MHz maximum clock speed, 4 KB program memory, 232-byte RAM, hardware multiply, 8-level hardware stack, 33 I/O pins, and integrated peripherals: a USART, two PWM modules, a watchdog timer, and power-on reset. The device operates from 4.5 V to 6.0 V across the -40 C to +125 C extended temperature range, fitting industrial and consumer embedded roles.
Architecture-wise, PIC17C42A uses a Harvard RISC core with a 16-bit instruction word and 8-bit data path. The 33 I/O pins share ports RB, RC, and RD; pinout compatibility with PIC16C5X/PIC12CXXX/PIC16CXX lets designers migrate firmware upward while keeping the existing PCB layout.
Applications include industrial control, automotive subsystems, consumer electronics, and embedded control where 8-bit simplicity and OTP cost advantages matter. The PIC17C42A is a mature part; Microchip recommends PIC18F4220 for new designs. Drop-in alternatives exist within the same family (PIC17C42A-16/P, PIC17C42A-16E/L, PIC17C42A-16E/PQ) to cover packaging, speed, and temperature variants.
When designing in this MCU, account for OTP (no firmware updates in-field), confirm supply is within 4.5-6.0 V, and reserve the MCLR pin for proper reset. This page consolidates distributor pricing, verified drop-in alternatives, and practical engineering notes not aggregated on any single manufacturer page.
Drop-in alternatives for PIC17C42A-16E/P — 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 PIC17C42A-16E/P (same form factor and footprint) — differing in Package, Mounting Type, Program Memory Type, Program Memory Size, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C42A-16/P
✅ Drop-In✓ In Stock
$7.45 / Unit
View Datasheet →PIC17C42A-16E/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C42A-16E/PQ
✅ Drop-In✓ In Stock
$6.08 / Unit
View Datasheet →PIC17C42AT-16I/PQ
✅ Drop-In✓ In Stock
$6.95 / Unit
View Datasheet →PIC17C42A-16I/P
✅ Drop-In✓ In Stock
$4.1 / Unit
View Datasheet →PIC17C42A-16E/P Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit Microcontroller (MCU) |
| Series | PIC17C |
| Program Memory Size | 4 KB (2K x 16) |
| Program Memory Type | OTP (One-Time Programmable) |
| RAM Size | 232 bytes (232 x 8) |
| Maximum Clock Frequency | 16 MHz |
| Instruction Execution Time | 121 ns (8.25 MIPS) |
| Number of I/O Pins | 33 |
| Package | 40-pin PDIP (0.600", 15.24 mm) |
| Oscillator Type | External |
| Supply Voltage Range | 4.5 V to 6.0 V |
| Operating Temperature Range | -40 C to +125 C (Extended, "E") |
| Integrated Peripherals | USART, PWM x2, Watchdog Timer (WDT), Power-On Reset (POR) |
| Mounting Type | Through-Hole |
| Lead-Free / RoHS | Compliant |
| Instruction Set | 58 single-word instructions, RISC, Harvard architecture |
PIC17C42A-16E/P Pin Configuration
| Pin 1 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| Pin 2 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| Pin 3 | RA2/AN2 — Port A bit 2 / Analog input 2 |
| Pin 4 | RA3/AN3 — Port A bit 3 / Analog input 3 |
| Pin 5 | RA4/T0CKI — Port A bit 4 / Timer 0 clock input |
| Pin 6 | RA5/SS — Port A bit 5 / SPI slave select |
| Pin 7 | OSC1 — Oscillator input |
| Pin 8 | OSC2 — Oscillator output |
| Pin 9 | MCLR — Master clear (reset) input |
| Pin 10 | VSS — Ground |
| Pin 11 | VDD — Positive supply (4.5-6.0 V) |
| Pin 12 | RB0/INT — Port B bit 0 / External interrupt |
| Pin 13 | RB1 — Port B bit 1 |
| Pin 14 | RB2 — Port B bit 2 |
| Pin 15 | RB3 — Port B bit 3 |
| Pin 16 | RB4 — Port B bit 4 |
| Pin 17 | RB5 — Port B bit 5 |
| Pin 18 | RB6 — Port B bit 6 |
| Pin 19 | RB7 — Port B bit 7 |
| Pin 20 | RC0 — Port C bit 0 |
| Pin 21 | RC1 — Port C bit 1 |
| Pin 22 | RC2 — Port C bit 2 |
| Pin 23 | RC3 — Port C bit 3 |
| Pin 24 | RC4 — Port C bit 4 |
| Pin 25 | RC5 — Port C bit 5 |
| Pin 26 | RC6 — Port C bit 6 |
| Pin 27 | RC7 — Port C bit 7 |
| Pin 28 | RD0 — Port D bit 0 |
| Pin 29 | RD1 — Port D bit 1 |
| Pin 30 | RD2 — Port D bit 2 |
| Pin 31 | RD3 — Port D bit 3 |
| Pin 32 | RD4 — Port D bit 4 |
| Pin 33 | RD5 — Port D bit 5 |
| Pin 34 | RD6 — Port D bit 6 |
| Pin 35 | RD7 — Port D bit 7 |
| Pin 36 | RE0 — Port E bit 0 |
| Pin 37 | RE1 — Port E bit 1 |
| Pin 38 | RE2 — Port E bit 2 |
| Pin 39 | VSS — Ground (secondary) |
| Pin 40 | VDD — Positive supply (secondary) |
Typical Applications
PIC17C42A-16E/P is suitable for 6 applications: Industrial Control Systems, Automotive Subsystems, Consumer Electronics Embedded Control, Motor Control and PWM Drive, Serial Communication Master (USART), Legacy Equipment Maintenance.
Industrial Control Systems
The PIC17C42A-16E/P fits industrial control with 33 programmable I/O lines and 16 MHz / 8.25 MIPS throughput, enough to scan sensors, drive relays, and host a USART link to a host PLC. Its 4.5-6.0 V supply and -40 C to +125 C extended temperature range tolerate factory-floor electrical noise and ambient swings. The integrated PWM modules allow direct motor or valve control without external drivers.
Recommended
Automotive Subsystems
The PIC17C42A-16E/P is used in non-safety automotive subsystems (interior lighting, climate panel, accessory controllers) where the -40 C to +125 C range and 5 V supply align with 12 V-bus-derived rails. The 33 I/O pins comfortably drive switches and read sensors; two PWM channels handle dimming or fan speed. OTP memory locks firmware at production, preventing unauthorized field modification.
Recommended
Consumer Electronics Embedded Control
The PIC17C42A-16E/P serves consumer appliances (washing machines, microwave ovens, smart thermostats) where cost per node matters and OTP memory is acceptable once firmware is locked. Its 58-instruction RISC core is simple to program in assembly or C, and the integrated USART supports a low-cost display or keypad module. The 16 MHz throughput handles user-interface tasks and basic motor sequencing.
Recommended
Motor Control and PWM Drive
The PIC17C42A-16E/P's two on-chip PWM modules and 33 I/O lines support DC motor speed control, stepper sequencing, or LED dimming. The 16 MHz clock produces 8.25 MIPS, ample for software PID loops while offloading the PWM to hardware. Integrated WDT ensures fault recovery if the control loop stalls, critical in unattended motor applications.
Recommended
Serial Communication Master (USART)
The PIC17C42A-16E/P's integrated USART allows it to act as a bridge between sensors, displays, or modems over RS-232/RS-485. The 8.25 MIPS core handles protocol parsing alongside I/O scanning. With 232 bytes RAM, the MCU can buffer short messages before forwarding. Industrial bus nodes and remote sensor interfaces commonly use this configuration.
Recommended
Legacy Equipment Maintenance
The PIC17C42A-16E/P supports existing equipment where the original OTP part is failing and a like-for-like replacement is needed. Microchip still produces limited quantities for maintenance markets. Engineers servicing installed-base systems (industrial controllers, older HVAC units, legacy medical device subassemblies) can source this part through authorized distributors rather than redesigning the board.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C42A-16E/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C42A-16/P | PIC17C42A-16E/L | PIC17C42A-16E/PQ | PIC17C42AT-16I/PQ | PIC17C42A-16I/P |
|---|---|---|---|---|---|---|
| Package | 40-pin PDIP (0.600") | 40-pin PDIP (same) | 44-pin PLCC (different footprint) | 44-pin MQFP (different footprint) | 44-pin MQFP (different footprint) | 40-pin PDIP (same) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 4 KB OTP | 4 KB OTP | 4 KB OTP | 4 KB OTP | 4 KB OTP | 4 KB OTP |
| Max Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz |
| Operating Temperature | -40 C to +125 C (Extended) | 0 C to +70 C (Commercial) | -40 C to +125 C (Extended) | -40 C to +125 C (Extended) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) |
| Supply Voltage | 4.5 V to 6.0 V | 4.5 V to 6.0 V | 4.5 V to 6.0 V | 4.5 V to 6.0 V | 4.5 V to 6.0 V | 4.5 V to 6.0 V |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| Memory Type | OTP | OTP | OTP | OTP | OTP | OTP |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND |
Key Differentiators
- Drop-in 40-PDIP PIC17C42A-16/P at commercial temperature (vs PIC17C42A-16/P)
- Surface-mount 44-PLCC alternative with same electrical specs (vs PIC17C42A-16E/L)
- Compact 44-MQFP variant for space-constrained boards (vs PIC17C42A-16E/PQ)
- Modern flash-based successor with upward compatibility (vs PIC18F4220)
Design Notes
Place a 100 nF ceramic decoupling capacitor as close as possible to the VDD pin (pin 11) with the ground return to the nearest VSS pin (pin 10). Per Microchip datasheet DS30412C, the supply range is 4.5 V to 6.0 V; operation outside this window may cause erratic instruction execution. For noisy industrial environments, add a 10 uF bulk capacitor on the VDD rail and consider a ferrite bead if switching loads share the supply.
The MCLR pin (pin 9) must be tied to VDD through a 10 kohm pull-up resistor for normal operation; floating MCLR will cause unpredictable resets. The oscillator pins (OSC1/OSC2) require a proper crystal or external clock; do not leave them floating. The OTP program memory cannot be erased or rewritten - confirm firmware is final before programming. Per datasheet DS30412C, configuration bits must be set correctly to enable the watchdog timer and brown-out reset if needed.
The 40-pin PDIP footprint uses 0.100 inch (2.54 mm) row pitch and 0.600 inch (15.24 mm) body width. Per datasheet DS30412C, keep traces short on oscillator and reset pins to avoid noise pickup. If migrating to PIC17C42A-16E/L (44-PLCC) or PIC17C42A-16E/PQ (44-MQFP), the PCB land pattern must change - these are NOT direct PCB drop-ins despite electrical compatibility.
Per datasheet DS30412C, the PIC17C42A-16E/P's extended -40 C to +125 C range covers most industrial and automotive environments without additional thermal management. The CMOS process generates minimal heat; however, in enclosed housings above 85 C ambient, ensure the case temperature stays within spec by venting the enclosure or derating adjacent high-power components.
Compliance Information
RoHS and REACH compliance inferred from Microchip product page (not explicitly stated in verified web snippets); halogen-free status not specified in retrieved data. Not AEC-Q100 qualified - for automotive safety-critical applications, use PIC18F4220.
