PIC16C57C-20I/P - 8-bit 20MHz OTP MCU 3KB | Microchip
MPN: PIC16C57C-20I/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.85 | $3.85 |
| 10 | $3.42 | $34.20 |
| 100 | $2.98 | $298.00 |
| 500 | $2.55 | $1,275.00 |
| 1,000 | $2.18 | $2,180.00 |
PIC16C57C-20I/P Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (ROM/Flash/OTP), data RAM, and programmable I/O peripherals. The PIC16C5X family belongs to the broader 8-bit MCU category, which sits beneath 16-bit and 32-bit MCUs in the embedded computing hierarchy. 8-bit OTP MCUs like the PIC16C57C are designed for cost-sensitive, high-volume embedded control where code is finalized at production time and does not require field updates - common in appliances, toys, and industrial sensor nodes.
Key features include a 12-bit instruction word for 2:1 code compression versus competing 8-bit architectures, only 33 single-word instructions for fast learning curve, 100 ns instruction execution time at 20 MHz, and a two-stack hardware subroutine return stack. The device supports both RC and crystal/ceramic resonator oscillator modes, watchdog timer with on-chip RC oscillator, and programmable code protection.
The PIC16C57C uses a Harvard architecture with separate program and data buses, eliminating fetch-decode bottlenecks. Its 12-bit wide instruction set is symmetrical and orthogonal, allowing any register to act as an accumulator or address pointer. Power-on Reset (POR), Power-up Timer (PWRT), and Oscillator Start-up Timer (OST) ensure clean cold-start behavior without external reset circuitry.
Typical applications include appliance control (washing machines, microwaves), automotive sub-systems (sensor interfaces, simple body controllers), industrial timers and counters, remote controls, and battery-powered sensor nodes. The 20 I/O lines comfortably drive LED arrays, keypads, and low-speed serial interfaces.
When designing, allow for OTP one-time programming by using a production programmer and plan code carefully - there is no in-system reprogramming. Use the watchdog timer for unattended industrial deployments and follow Microchip's recommended decoupling (0.1 uF ceramic on VDD) plus bulk electrolytic on the board supply rail.
This page synthesizes distributor pricing, verified drop-in alternatives from the same PIC16C5X family, and practical design notes not aggregated in any single manufacturer page, giving procurement and design engineers a faster path to sourcing and migrating legacy 8-bit designs.
Drop-in alternatives for PIC16C57C-20I/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 PIC16C57C-20I/P (same form factor and footprint) — differing in Package, Timers, Program Memory Type, Operating Temperature, Watchdog Timer.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C57C-20I/SP
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →PIC16C57C-20E/SP
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →PIC16C57-10/P
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →PIC16C56-LP/P
✅ Drop-In✓ In Stock
$3.39 / Unit
View Datasheet →PIC16C57C-20I/P Maximum Ratings & Electrical Characteristics
| Core | PIC16C 8-bit RISC |
| Maximum Clock Frequency | 20 MHz |
| Instruction Execution Time | 100 ns at 20 MHz |
| Program Memory Type | OTP (One-Time-Programmable) ROM |
| Program Memory Size | 3 KB (2K x 12) |
| Data RAM | 72 bytes |
| I/O Pins | 20 |
| Instruction Set | 33 single-word instructions, 12-bit wide |
| Package | 28-pin PDIP (Plastic DIP) |
| Operating Temperature Range | -40C to +85C (Industrial, "I" grade) |
| Operating Voltage Range | 2.5 V to 6.25 V |
| Architecture | Harvard (separate program/data buses) |
| Hardware Stack | 2 levels |
| Oscillator Modes | RC, Crystal, Ceramic Resonator |
| Watchdog Timer | Yes (on-chip RC oscillator) |
| Power-on Reset / PWRT / OST | Yes |
| Code Protection | Programmable |
| Mounting Type | Through-Hole |
| MSL Level | Not applicable (through-hole) |
PIC16C57C-20I/P Pin Configuration
| Pin 1 | VDD — Positive supply voltage (2.5V to 6.25V) |
| Pin 2 | RA2 — Port A bit 2 (bidirectional digital I/O) |
| Pin 3 | T0CKI/RA3 — Timer0 external clock input / Port A bit 3 |
| Pin 4 | MCLR — Master Clear (active-low reset input) |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0 — Port B bit 0 (bidirectional digital I/O, interrupt-on-change) |
| Pin 7 | RB1 — Port B bit 1 (bidirectional digital I/O) |
| Pin 8 | RB2 — Port B bit 2 (bidirectional digital I/O) |
| Pin 9 | RB3 — Port B bit 3 (bidirectional digital I/O) |
| Pin 10 | RB4 — Port B bit 4 (bidirectional digital I/O, interrupt-on-change) |
| Pin 11 | RB5 — Port B bit 5 (bidirectional digital I/O) |
| Pin 12 | RB6 — Port B bit 6 (bidirectional digital I/O) |
| Pin 13 | RB7 — Port B bit 7 (bidirectional digital I/O) |
| Pin 14 | VSS — Ground reference (second VSS pin) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / clock output |
| Pin 16 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 17 | RC0 — Port C bit 0 (bidirectional digital I/O) |
| Pin 18 | RC1 — Port C bit 1 (bidirectional digital I/O) |
| Pin 19 | RC2 — Port C bit 2 (bidirectional digital I/O) |
| Pin 20 | RC3 — Port C bit 3 (bidirectional digital I/O) |
| Pin 21 | RC4 — Port C bit 4 (bidirectional digital I/O) |
| Pin 22 | RC5 — Port C bit 5 (bidirectional digital I/O) |
| Pin 23 | RC6 — Port C bit 6 (bidirectional digital I/O) |
| Pin 24 | RC7 — Port C bit 7 (bidirectional digital I/O) |
| Pin 25 | RA0 — Port A bit 0 (bidirectional digital I/O) |
| Pin 26 | RA1 — Port A bit 1 (bidirectional digital I/O) |
| Pin 27 | VSS — Ground reference (third VSS pin) |
| Pin 28 | VDD — Positive supply voltage (second VDD pin) |
Typical Applications
PIC16C57C-20I/P is suitable for 7 applications: Appliance Control Boards, Remote Controls and IR Transmitters, Industrial Timers and Counters, Automotive Sub-System Controllers, Battery-Powered Sensor Nodes, Toy and Hobby Electronics, LED Display and Signage Drivers.
Appliance Control Boards
The PIC16C57C-20I/P fits appliance control boards (washing machines, microwave ovens, dishwashers) because its 20 MHz core executes 100 ns instructions for real-time relay and motor control, while the 3KB OTP program memory holds complete state-machine firmware for cycle sequencing and sensor polling. Its 20 digital I/O lines comfortably drive 7-segment displays, keypads, buzzer drivers, and triac interfaces. The industrial -40C to +85C temperature grade survives under-cabinet heat and humid bathroom environments. The OTP architecture keeps unit cost low versus Flash, since appliance firmware is finalized at production. Pin compatibility with the broader PIC16C5X family means design teams can migrate to PIC16F57 for new SKUs without re-laying the 28-pin PDIP board.
Recommended
Remote Controls and IR Transmitters
The PIC16C57C-20I/P is a strong fit for TV, audio, and HVAC remote controls because its low pin count, low BOM cost, and 2.5 V to 6.25 V operating range can run directly from 2x AA cells without a voltage regulator. The 20 MHz core easily generates 38 kHz carrier waveforms for IR transmission using timer-based bit-banging, and 72 bytes RAM holds button matrix state plus protocol encoding buffers. Industrial temperature grade tolerates glove-touch environments and consumer drop-test thermal cycling. OTP memory prevents casual firmware theft - critical for OEM-branded remotes. Designers commonly pair this MCU with a TSOP38238 IR receiver on the receiver side and a discrete NPN transistor driving the IR LED.
Recommended
Industrial Timers and Counters
The PIC16C57C-20I/P serves industrial timer and counter modules well thanks to its built-in watchdog timer with on-chip RC oscillator, hardware TMR0 with external T0CKI pin for pulse counting, and 20 MHz throughput that supports fast quadrature decoding and event logging. The PIC16C 8-bit core's predictable interrupt latency and 12-bit instruction set make PID control loops straightforward to code. The 28-pin PDIP through-hole package withstands vibration in control cabinet installations better than fine-pitch surface-mount alternatives. Pair with an external RTC like the MCP79410 for time-of-day scheduling, or use the on-chip TMR0 for sub-second timing loops.
Recommended
Automotive Sub-System Controllers
The PIC16C57C-20I/P can be deployed in non-safety automotive sub-systems such as seat controller keypads, mirror-position memory, ambient lighting, and accessory timer modules. Its industrial temperature grade handles cabin environments, while the 20 I/O lines drive LED drivers and read Hall-effect position sensors. Note that AEC-Q100 qualification is NOT specified for this part; for under-hood or safety-critical automotive designs, Microchip's PIC16F variants with Q1 (AEC-Q100) suffix should be selected instead. OTP memory protects aftermarket firmware tampering. The 28-pin PDIP footprint remains compatible with Microchip's pin-compatible flash PIC16F57, easing future migration.
Recommended
Battery-Powered Sensor Nodes
The PIC16C57C-20I/P operates from 2.5 V to 6.25 V, making it directly compatible with 2x or 3x AA alkaline cells or a single Li-ion cell without a boost regulator. Its CMOS process and 8-bit RISC architecture keep active current low enough for weeks of battery life when the MCU spends most of its time in sleep mode, waking periodically on watchdog or pin-change interrupts. The 72 bytes RAM is sufficient for a handful of sensor readings, and the 20 I/O lines support multiple analog sensors via simple resistor-divider reads on digital inputs. OTP prevents accidental code drift in deployed sensor nodes. Suitable for simple thermostats, leak detectors, and remote weather stations.
Recommended
Toy and Hobby Electronics
The PIC16C57C-20I/P is a workhorse for hobby robots, electronic toys, and educational kits where its 20 MHz core drives PWM motor control, servo outputs, and addressable LED chains. The 28-pin PDIP through-hole package is breadboard-friendly - students and makers can plug it directly into a solderless breadboard without fine-pitch SMD adapters. The 3KB OTP holds complete line-follower or sumobot behaviors, and the 33-instruction RISC set is one of the easiest for beginners to learn. Pair with an L293D H-bridge driver for DC motor control and HC-SR04 ultrasonic sensors for obstacle detection.
Recommended
LED Display and Signage Drivers
The PIC16C57C-20I/P drives multiplexed LED matrix displays, 7-segment counters, and scrolling marquee signs by using its 20 I/O lines to sink column drivers and source row drivers with software PWM for brightness control. The 20 MHz execution rate sustains refresh frequencies above 100 Hz for 8x8 matrix panels without visible flicker. The 3KB OTP stores lookup tables for character fonts and animation sequences. Industrial temperature grade covers outdoor signage in moderate climates. For larger displays, daisy-chain multiple boards via SPI or UART and use the PIC's hardware UART for inter-board communication.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57C-20I/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C57C-20I/SP | PIC16C57C-20E/SP | PIC16C57-10/P | PIC16C56-LP/P |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin PDIP | 28-pin PDIP - same | 28-pin PDIP - same | 28-pin PDIP - same | 28-pin PDIP - same |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 10 MHz | 40 kHz (LP oscillator variant) |
| Program Memory (OTP) | 3 KB (2K x 12) | 3 KB | 3 KB | 2 KB | 1 KB |
| Data RAM | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 25 bytes |
| I/O Pins | 20 | 20 | 20 | 20 | 12 |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +125C (Extended) | -40C to +85C (Industrial) | 0C to +70C (Commercial) |
| Operating Voltage | 2.5 V to 6.25 V | 2.5 V to 6.25 V | 2.5 V to 6.25 V | 2.5 V to 6.25 V | 2.5 V to 6.25 V |
| Unit Price (qty 1, approx) | $3.85 | ~$3.85 | ~$4.10 | ~$3.20 | ~$2.95 |
Key Differentiators
- Higher maximum clock speed than the legacy PIC16C57 base silicon (vs PIC16C57-10/P)
- Extended temperature grade option available in same footprint (vs PIC16C57C-20I/SP)
- More program memory and RAM than smaller PIC16C5X siblings (vs PIC16C56-LP/P)
Design Notes
Decouple VDD with a 0.1 uF ceramic capacitor placed within 5 mm of pins 1 and 28, plus a bulk electrolytic (10 uF or larger) on the board supply rail. The PIC16C57C draws brief current spikes during internal clock-edge events, and inadequate decoupling causes erratic code execution or POR misfires. For battery-powered designs, route the MCLR pin through a 10 kohm pull-up to VDD and add a 0.1 uF cap to ground to slow the rising edge and give the PWRT time to stabilize VDD before code execution begins.
Place the oscillator crystal or ceramic resonator as close as possible to OSC1 (pin 16) and OSC2 (pin 17) to minimize parasitic capacitance. Use short, symmetric traces and surround them with a ground pour to reduce EMI coupling. For high-noise environments (motor control, relay switching), add a 100 ohm series resistor in series with OSC2 to dampen overshoot. If using an external CMOS clock source, drive only OSC1 and leave OSC2 floating per Microchip's oscillator guidelines.
The PIC16C57C's 2-level hardware stack means subroutines cannot be nested more than two deep - exceeding this causes stack underflow and unpredictable jumps to address 0x000. Plan firmware architecture to avoid deep CALL nesting or refactor into iterative code. OTP memory is one-time programmable: a single bad bit requires scrapping the part. Always verify on a windowed or flash-equivalent part (PIC16F57) before committing production OTP units. Finally, the watchdog timer (WDT) has its own on-chip RC oscillator independent of the system clock, so it continues to run even in sleep mode - do not forget to clear WDT in long blocking loops.
Compliance Information
RoHS, REACH, lead-free and halogen-free status were not explicitly listed in verified distributor data; request latest material declaration from Microchip. PIC16C57C-20I/P is not AEC-Q100 qualified - choose "Q1" automotive suffixes for AEC-Q100 applications. Microchip publishes a Conflict Minerals Declaration covering all PIC microcontrollers.
