PIC16C57-LP/P - 8-Bit OTP MCU, 3KB, 20 I/O, 28-DIP | Microchip
MPN: PIC16C57-LP/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.95 | $2.95 |
| 10 | $2.62 | $26.20 |
| 100 | $2.21 | $221.00 |
| 500 | $1.95 | $975.00 |
| 1,000 | $1.74 | $1,740.00 |
PIC16C57-LP/P Overview
What is a PIC16C5X microcontroller? The PIC16C5X is Microchip's original low-cost, high-performance 8-bit fully-static OTP/EPROM microcontroller family. In the broader taxonomy it sits as an 8-bit microcontroller -> general-purpose MCU -> embedded controller -> semiconductor. The OTP variants are intended for prototype runs and small-to-medium production where field firmware updates are not required; ROM-mask parts serve high-volume programs. The PIC16C57 is the largest-memory member of the family and is one of the longest-running legacy 8-bit cores still supported by modern MPLAB tools.
Key features of the PIC16C57-LP/P include an 8-bit real-time clock/counter (TMR0) with an 8-bit programmable prescaler, a watchdog timer for unattended recovery, power-saving SLEEP mode, on-chip RC oscillator support, and an internal interrupt structure. The device supports a four-clock-per-instruction cycle and provides 33 single-word instructions. The 20 I/O pins are bidirectional with individually programmable direction registers, and each can source/sink sufficient current to directly drive LEDs in many applications, simplifying the external bill of materials.
Technically, the PIC16C57 uses a Harvard architecture with separate program and data buses, enabling simultaneous instruction fetch and data access. Power consumption in the LP variant is optimized for battery-friendly designs, and the wide 2.5 V to 6.25 V supply range tolerates unregulated rails. The PIC16C57 is supported by MPLAB X IDE and the original MPLAB PM3 programmer for both PC-hosted and stand-alone programming flows.
Typical applications for the PIC16C57-LP/P include appliance controllers, low-end remote controls, simple sensor interfaces, LED drivers, hobby projects, and educational embedded platforms where a small, reliable 8-bit core is sufficient. Industrial uses cover timer modules, fan controllers, and basic HMI panels.
When designing with the PIC16C57-LP/P, verify the oscillator mode (LP, XT, RC, HS) by suffix - the LP suffix specifies the low-power oscillator mode intended for 32.768 kHz watch crystals and very low standby current. Engineers migrating to a flash-based core should consider the PIC16F57 family for in-circuit reprogrammability on the same 28-pin footprint.
This page synthesizes distributor stock and pricing, drop-in alternative MPNs, application-specific guidance, and engineering design notes - not just a restatement of the manufacturer datasheet.
Drop-in alternatives for PIC16C57-LP/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 PIC16C57-LP/P (same form factor and footprint) — differing in Package, Program Memory Size, Timers, Watchdog Timer, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C57C-40/P
✅ Drop-In✓ In Stock
$3.82 / Unit
View Datasheet →PIC16F57-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C57-10I/P
✅ Drop-In✓ In Stock
$1.75 / Unit
View Datasheet →PIC16C57-HSI/P
✅ Drop-In✓ In Stock
$1.89 / Unit
View Datasheet →PIC16C56-LP/P
✅ Drop-In✓ In Stock
$3.39 / Unit
View Datasheet →PIC16C55-LP/P
✅ Drop-In✓ In Stock
$1.45 / Unit
View Datasheet →PIC16C57-LP/P Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC Harvard |
| Family | PIC16C5X |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 3 KB (2K x 12) |
| RAM | 72 bytes |
| I/O Pins | 20 |
| Instruction Width | 12-bit |
| Data Bus Width | 8-bit |
| Instruction Set Size | 33 single-word instructions |
| Supply Voltage | 2.5 V to 6.25 V |
| Oscillator Mode (suffix) | LP (low-power, 32.768 kHz typical) |
| Maximum Frequency | 40 kHz (LP oscillator mode) |
| Timers | TMR0 (8-bit with 8-bit prescaler) |
| Watchdog Timer | Yes (on-chip WDT) |
| Hardware Stack | 2-level |
| Addressing Modes | Direct, Indirect, Relative |
| Package | 28-pin PDIP (DIP-28, 0.600" / 15.24 mm) |
| Mounting Type | Through-Hole |
| Operating Temperature | 0C to +70C |
| RoHS Status | Compliant |
PIC16C57-LP/P Pin Configuration
| Pin 1 | RA0 — Bidirectional I/O port A bit 0 |
| Pin 2 | RA1 — Bidirectional I/O port A bit 1 |
| Pin 3 | RA2 — Bidirectional I/O port A bit 2 |
| Pin 4 | RA3 — Bidirectional I/O port A bit 3 |
| Pin 5 | T0CKI — Timer0 clock input / RA4 |
| Pin 6 | OSC1 — Oscillator crystal input (LP mode: 32.768 kHz watch crystal) |
| Pin 7 | OSC2 — Oscillator crystal output |
| Pin 8 | VSS — Ground reference |
| Pin 9 | RB0 — Bidirectional I/O port B bit 0 |
| Pin 10 | RB1 — Bidirectional I/O port B bit 1 |
| Pin 11 | RB2 — Bidirectional I/O port B bit 2 |
| Pin 12 | RB3 — Bidirectional I/O port B bit 3 |
| Pin 13 | RB4 — Bidirectional I/O port B bit 4 |
| Pin 14 | RB5 — Bidirectional I/O port B bit 5 |
| Pin 15 | RB6 — Bidirectional I/O port B bit 6 |
| Pin 16 | RB7 — Bidirectional I/O port B bit 7 |
| Pin 17 | RC0 — Bidirectional I/O port C bit 0 |
| Pin 18 | RC1 — Bidirectional I/O port C bit 1 |
| Pin 19 | VSS — Ground reference (secondary) |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RC2 — Bidirectional I/O port C bit 2 |
| Pin 22 | RC3 — Bidirectional I/O port C bit 3 |
| Pin 23 | RC4 — Bidirectional I/O port C bit 4 |
| Pin 24 | RC5 — Bidirectional I/O port C bit 5 |
| Pin 25 | RC6 — Bidirectional I/O port C bit 6 |
| Pin 26 | RC7 — Bidirectional I/O port C bit 7 |
| Pin 27 | MCLR — Master clear reset (active low) |
| Pin 28 | VDD — Positive supply voltage (secondary) |
Typical Applications
PIC16C57-LP/P is suitable for 6 applications: Appliance Timer Controllers, Remote Control and IR Transmitter Keypads, Educational 8-Bit Embedded Platform, LED Display and Sign Drivers, Industrial Sensor Interface Modules, Hobby and Maker Projects.
Appliance Timer Controllers
The PIC16C57-LP/P's 33-instruction set, 2-level hardware stack, and 20 I/O pins make it ideal for fixed-function appliance timer boards such as washing-machine delay relays, microwave keypads, and dishwasher cycle sequencers. The LP (32 kHz) oscillator variant holds power consumption below 1 mA active for energy-conscious designs, while OTP memory locks firmware to prevent field tampering. Engineers can wire the 20 I/O pins directly to relays, LEDs, and a 4x4 membrane keypad without external mux logic. Real-world designs use the on-chip TMR0 prescaler to generate 1-second ticks from the 32.768 kHz crystal, eliminating an external RTC chip. Compared to 16-bit alternatives, the PIC16C57 reduces BOM cost by roughly 30-40% in single-function appliance products.
Recommended
Remote Control and IR Transmitter Keypads
The PIC16C57-LP/P is a classic fit for IR remote controls and consumer keypads where the device generates 38 kHz carrier modulation, scans a matrix keypad, and drives an IR LED via one of its 20 I/O pins. The 3 KB OTP program memory accommodates dozens of device codes and protocol stacks (RC-5/RC-6/NEC) with headroom for custom button mapping. Its 2.5 V to 6.25 V supply range is friendly to 3 V coin-cell or 2xAA battery stacks, and the LP oscillator allows standby currents under 10 uA in SLEEP for multi-year battery life. The Harvard architecture with 12-bit instructions delivers deterministic instruction timing, which simplifies carrier generation timing budgets versus von-Neumann 8-bit cores. A typical design uses TMR0 plus a software loop to synthesize the carrier without any external timer IC.
Recommended
Educational 8-Bit Embedded Platform
The PIC16C57-LP/P is widely used in universities and self-learners as a teaching vehicle for assembly programming and embedded fundamentals. The 33-instruction RISC-style set, 2-level hardware stack, and direct/indirect/relative addressing modes expose every core embedded concept without overwhelming beginners, while the 20 I/O pins give enough breadboard-friendly signals to wire switches, LEDs, and character LCDs. With MPLAB X IDE plus a PICkit programmer, students can step through code at instruction granularity even though the part is OTP (development uses windowed or flash equivalents). The PIC16C57 is also a popular reference design for teaching the Harvard architecture in undergraduate computer-engineering courses.
Recommended
LED Display and Sign Drivers
In low-density LED signs, scrolling marquees, and indicator panels, the PIC16C57-LP/P can multiplex up to 8x8 LED matrices using its 20 I/O pins as row/column drivers with external transistor buffers. The 33-instruction core is fast enough at the LP oscillator's 32.768 kHz to refresh small matrices via software timing loops without dedicated PWM peripherals. With 3 KB OTP program memory, designers can store multiple font tables and animation sequences. The 2.5 V to 6.25 V supply accepts 3.3 V or 5 V LED driver rails directly, simplifying the power tree. Compared to higher-pin-count MCUs, the PIC16C57 provides just enough I/O for cost-sensitive signage while keeping the instruction set easy to learn.
Recommended
Industrial Sensor Interface Modules
The PIC16C57-LP/P serves fixed-function industrial sensor conditioners that digitize analog signals via an external ADC and present readings over a simple UART or 4-20 mA loop. The PIC16C57's 2-level hardware stack and small RAM footprint are sufficient when each module runs a single, deterministic firmware build with no operating system. The LP oscillator's low power consumption allows loop-powered 4-20 mA sensor heads that draw under 3.5 mA total, leaving the loop current budget for the actual measurement. Engineers appreciate the 20 I/O count for driving indicator LEDs, reading calibration switches, and clocking the external ADC. Industrial users often standardize on the PIC16C57 across a sensor family to share firmware libraries.
Recommended
Hobby and Maker Projects
The PIC16C57-LP/P remains a popular part in DIY electronics, retrocomputing, and homebrew computer projects where enthusiasts build 8-bit trainers, single-board controllers, and breadboard prototypes. With 20 I/O pins, 3 KB OTP, and an extremely low unit cost, the device is a frequent substitute for the larger PIC16F84 in cost-constrained builds. Its 28-pin PDIP package fits standard perfboards and ZIF sockets, which are preferred for OTP programming flows with the MPLAB PM3. The 32.768 kHz LP oscillator also lets hobbyists experiment with low-power timekeeping, RTC emulation, and watch-crystal-based timing demos.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57-LP/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C57C-40/P | PIC16F57-I/P | PIC16C57-10I/P | PIC16C57-HSI/P | PIC16C56-LP/P | PIC16C55-LP/P |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | PDIP-28 (DIP-28, 0.600") | PDIP-28 - same | PDIP-28 - same | PDIP-28 - same | PDIP-28 - same | PDIP-28 - same | PDIP-28 - same |
| Program Memory | 3 KB OTP | 3 KB OTP | 3 KB Flash | 3 KB OTP | 3 KB OTP | 1 KB OTP | 512 B OTP |
| RAM | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 72 bytes |
| I/O Pins | 20 | 20 | 20 | 20 | 20 | 20 | 20 |
| Oscillator Mode | LP (low-power, 32 kHz) | 40 MHz HS | Industrial | 10 MHz HS | 20 MHz HS | LP | LP |
| Memory Type | OTP EPROM | OTP EPROM | Flash | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM |
| Operating Temperature | 0C to +70C (commercial) | 0C to +70C (commercial) | -40C to +85C (industrial) | -40C to +85C (industrial) | 0C to +70C (commercial) | 0C to +70C (commercial) | 0C to +70C (commercial) |
Key Differentiators
- Lowest active power in the PIC16C57 family (vs PIC16C57C-40/P)
- Reprogrammability for field updates (vs PIC16F57-I/P)
- Largest program memory of the PIC16C5X family (vs PIC16C56-LP/P)
Design Notes
Estimated: at VDD = 5 V and 32.768 kHz LP oscillator, active current is typically under 1 mA; in SLEEP mode the PIC16C57-LP/P draws single-digit microamps. Add a 100 nF decoupling capacitor as close as practical to pins 8/19 (VSS) and 20/28 (VDD). For battery-powered designs, route MCLR through a 10 kohm pull-up to VDD and add a reverse-polarity protection diode on the supply rail.
Keep the 32.768 kHz watch crystal traces short (under 5 mm) and surrounded by a ground guard to reduce stray capacitance, which would otherwise shift the oscillator off-frequency. Place the load capacitors (typically 12-22 pF) symmetrically between OSC1/OSC2 and ground. MCLR should be pulled high through 10 kohm and decoupled with 100 nF if not used as a reset source.
Do not assume any PIC16C5X family member can be substituted on a PIC16F57 board without verifying the configuration bits - OTP parts use factory programming of oscillator and WDT options, while flash parts let you reconfigure at runtime. Also note that the PIC16C57 has a 2-level hardware stack only; deep subroutine nesting will cause stack underflow and unexpected resets. Plan call depth accordingly.
Because the PIC16C57-LP/P runs from a 32 kHz oscillator, its GPIO edges are slow (tens of microseconds rise/fall depending on load). For designs that interface with fast peripherals, add 1 kohm series resistors or use external buffers. If driving long cables or relays, clamp inductive kickback with a 1N4148 diode across the coil to protect the I/O pin.
Compliance Information
RoHS/REACH compliance per JLCPCB listing (2026-09-17). Halogen-free status not explicitly stated in the verified web data and left as unknown. Not AEC-Q100 qualified; industrial-grade parts in the same family (PIC16F57-I/P, PIC16C57-10I/P) extend the operating range to -40C to +85C but still do not carry AEC-Q100.
