PIC16C57-RC/SS - 8-Bit EPROM MCU, 3KB OTP, 4MHz, SSOP-28
MPN: PIC16C57-RC/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.75 | $4.75 |
| 10 | $4.27 | $42.70 |
| 100 | $3.8 | $380.00 |
| 500 | $3.42 | $1,710.00 |
| 1,000 | $3.04 | $3,040.00 |
PIC16C57-RC/SS Overview
What is an 8-bit OTP microcontroller? It is a small, low-cost CMOS processor with a Harvard architecture in which the program is stored in one-time-programmable EPROM (or mask ROM) and the data in a small on-chip RAM. OTP microcontrollers belong to the broader hierarchy of microcontrollers (MCU) -> embedded controllers -> semiconductors. They are widely deployed in cost-sensitive, high-volume, single-purpose appliances where the program is finalized in production and never needs in-field firmware updates. The PIC16C5X family specifically targets applications that need deterministic timing, low power consumption, and a tiny footprint without the overhead of flash-based MCUs.
Key features of the PIC16C57-RC/SS include a two-level deep hardware stack, direct/indirect/relative addressing modes for both data and instructions, an 8-bit real-time clock/counter (TMR0) with 8-bit programmable prescaler, power-on reset, watchdog timer with its own on-chip RC oscillator, and a power-saving SLEEP mode. The 20 I/O pins are bidirectional and individually programmable. The 4 MHz oscillator input supports RC, XT, HS, and LP modes within the family, though this RC variant is characterized for resistor-capacitor oscillator operation up to 4 MHz.
The PIC16C57 is fabricated on Microchip's CMOS process with low-power design techniques that yield typical active current of a few mA and standby (SLEEP) currents under 10 µA depending on clock configuration. Its Harvard memory architecture separates program (12-bit wide) and data (8-bit wide) buses, eliminating instruction fetch bottlenecks. Combined with single-cycle instruction execution at 4 MHz (250 ns instruction cycle), the device delivers roughly 4 MIPS of throughput - more than sufficient for motor control, user-interface scanning, and simple communication tasks.
Typical applications include appliance controls (washing machines, microwave ovens, rice cookers), consumer remote controls, battery chargers, smart sensors, HVAC thermostat control boards, and industrial timer/sequencer modules. Its deterministic execution and small footprint make it a long-time industry workhorse for cost-driven, high-volume embedded designs.
When designing with the PIC16C57-RC/SS, ensure your oscillator circuit follows Microchip's RC oscillator guidelines (R between 5 kΩ and 100 kΩ, C above 20 pF) for stable operation. Use the SLEEP mode aggressively in battery-powered applications; combined with the watchdog timer you can achieve average current well below 100 µA. Since the device is OTP (not flash), program verification must be done before final code commit.
This page synthesizes distributor pricing, drop-in alternative cross-references, and practical design notes that complement the manufacturer datasheet for engineers evaluating the PIC16C57-RC/SS for new or legacy designs.
Drop-in alternatives for PIC16C57-RC/SS — 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-RC/SS (same form factor and footprint) — differing in Maximum Clock Frequency, Program Memory Size, Program Memory Type, Core Architecture, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C57C-04/SS
✅ Drop-In✓ In Stock
$4.85 / Unit
View Datasheet →PIC16C57CT-04I/SS
✅ Drop-In✓ In Stock
$4.1 / Unit
View Datasheet →PIC16C57T-RC/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C57C-20I/SS
✅ Drop-In✓ In Stock
$0.9 / Unit
View Datasheet →PIC16F57-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C57-RC/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit RISC (Harvard) |
| Family | PIC16C5X |
| Program Memory Type | EPROM (One-Time Programmable, OTP) |
| Program Memory Size | 3 KB |
| RAM | 72 bytes |
| Instruction Word Width | 12 bits |
| Number of Instructions | 33 single-word/single-cycle |
| Maximum Clock Frequency | 4 MHz (RC grade) |
| Instruction Cycle Time | 250 ns @ 4 MHz |
| Supply Voltage Range | 3.0 V to 6.25 V |
| I/O Pins | 20 bidirectional |
| Timers | 1 x 8-bit TMR0 with 8-bit programmable prescaler |
| Stack Depth | 2 levels (hardware) |
| Watchdog Timer | Yes, with dedicated on-chip RC oscillator |
| Power-Saving Modes | SLEEP mode |
| Oscillator Modes Supported | RC, XT, HS, LP (this variant: RC, 4 MHz) |
| Package | 28-pin SSOP (5.30 mm width) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | 0C to +70C (commercial; industrial variants exist in same family) |
| RoHS Status | Compliant (per current Microchip product page) |
PIC16C57-RC/SS Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O, Port A bit 2 |
| Pin 2 | RA3 — Bidirectional I/O, Port A bit 3 |
| Pin 3 | RB0 — Bidirectional I/O, Port B bit 0 (interrupt on change) |
| Pin 4 | RB1 — Bidirectional I/O, Port B bit 1 |
| Pin 5 | RB2 — Bidirectional I/O, Port B bit 2 |
| Pin 6 | RB3 — Bidirectional I/O, Port B bit 3 |
| Pin 7 | RB4 — Bidirectional I/O, Port B bit 4 |
| Pin 8 | RB5 — Bidirectional I/O, Port B bit 5 |
| Pin 9 | RB6 — Bidirectional I/O, Port B bit 6 |
| Pin 10 | RB7 — Bidirectional I/O, Port B bit 7 |
| Pin 11 | RC0 — Bidirectional I/O, Port C bit 0 |
| Pin 12 | RC1 — Bidirectional I/O, Port C bit 1 |
| Pin 13 | RC2 — Bidirectional I/O, Port C bit 2 |
| Pin 14 | RC3 — Bidirectional I/O, Port C bit 3 |
| Pin 15 | RC4 — Bidirectional I/O, Port C bit 4 |
| Pin 16 | RC5 — Bidirectional I/O, Port C bit 5 |
| Pin 17 | RC6 — Bidirectional I/O, Port C bit 6 |
| Pin 18 | RC7 — Bidirectional I/O, Port C bit 7 |
| Pin 19 | GND — Ground |
| Pin 20 | VDD — Positive supply |
| Pin 21 | RA0 — Bidirectional I/O, Port A bit 0 |
| Pin 22 | RA1 — Bidirectional I/O, Port A bit 1 |
| Pin 23 | MCLR — Master clear reset (active low) |
| Pin 24 | NC — Not connected (per datasheet) |
| Pin 25 | OSC2/CLKOUT — Oscillator output / clock out |
| Pin 26 | OSC1/CLKIN — Oscillator input / clock in |
| Pin 27 | T0CKI — Timer0 clock input (shared with Port A) |
| Pin 28 | VDD — Positive supply (redundant) |
Typical Applications
PIC16C57-RC/SS is suitable for 6 applications: Washing Machine and Dishwasher Control, Microwave Oven and Rice Cooker Control, Universal Remote Control and IR Transmitter, Battery Charger and Smart Battery Management, HVAC Thermostat and Climate Control, Industrial Timer, Sequencer, and Counter Modules.
Washing Machine and Dishwasher Control
The PIC16C57-RC/SS is a long-standing workhorse for major-appliance motor and sequence control boards. Its 3 KB OTP program memory is sufficient to encode multi-step wash cycles, water-level sensing, door-lock interlocks, and motor-direction logic. The 4 MHz clock and 250 ns instruction cycle give deterministic response times for triac-fired load switches, while the watchdog timer resets the MCU safely on firmware lockup. With 20 I/O pins the part directly drives relay coils, buzzer PWM, and segmented-LED or LCD user interfaces without external logic. Compared with newer Flash MCUs the OTP architecture is a deliberate cost choice for high-volume, factory-programmed appliance production.
Recommended
Microwave Oven and Rice Cooker Control
Microwave and rice-cooker control boards benefit from the PIC16C57-RC/SS's low BOM count and deterministic 8-bit timing. The single TMR0 with 8-bit prescaler handles countdown timers up to several minutes while the main loop drives the magnetron triac, turntable motor relay, and 7-segment display. The 72-byte RAM holds active cooking state and the 3 KB program stores the menu of preset programs. The wide 3.0-6.25 V supply tolerance accommodates rectified 5 V or 3.3 V rails without additional regulators, lowering total cost. The SLEEP mode plus watchdog enables sub-100 µA standby current for digital-clock displays.
Recommended
Universal Remote Control and IR Transmitter
The PIC16C57-RC/SS powers cost-optimized IR remote controls where 3 KB of OTP program memory holds the protocol library for TV/VCR/DVD/audio brands. The 4 MHz oscillator and tight instruction timing generate accurate 38 kHz / 40 kHz carrier frequencies without an external timer IC. SLEEP mode with watchdog wakeup draws only a few microamps idle, so two AAA batteries can last for years. The 20 I/O pins easily accommodate a 4x4 or 5x5 key matrix plus an IR-LED driver pin, keeping the entire remote to a single IC plus a handful of passives.
Recommended
Battery Charger and Smart Battery Management
Linear and switch-mode battery chargers use the PIC16C57-RC/SS for charge-state sequencing, delta-V detection, and LED status indication. The OTP memory locks in validated charge algorithms that meet safety certifications, while the 20 I/O pins monitor temperature thermistors, current-sense amplifiers, and cell-voltage dividers. SLEEP mode between samples yields very low quiescent current so the charger itself draws negligible power from the battery when not charging. The 3.0-6.25 V supply range covers both 4-cell NiMH stacks (4.8 V) and 1S Li-ion (3.7 V) without an extra regulator.
Recommended
HVAC Thermostat and Climate Control
Thermostat control boards leverage the PIC16C57-RC/SS for time-proportional HVAC control, weekly scheduling, and LCD user interfaces. The 3 KB program memory holds scheduling, hysteresis, and filter-life tracking. The 8-bit TMR0 with prescaler drives a 1-second software clock for scheduling, and SLEEP mode with watchdog keeps average current low so the thermostat can run from 24 VAC with a simple half-wave supply. The 20 I/O pins interface to the keypad, LCD, and triac-driver optocouplers without external glue logic.
Recommended
Industrial Timer, Sequencer, and Counter Modules
Industrial timer and sequencer modules use the PIC16C57-RC/SS for deterministic event timing in PLC-like auxiliary controllers. The 4 MHz oscillator and 250 ns instruction cycle deliver accurate timing for relay-coil sequencing, conveyor-belt indexing, and machine-cycle counting. The 2-level hardware stack is sufficient for simple state machines, and the watchdog timer provides automatic recovery from electrical noise. With 20 I/O pins the MCU directly drives up to 16 inputs and 4 outputs, or 12 outputs and 8 inputs, fitting the majority of small-machine control panels.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57-RC/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C57C-04/SS | PIC16C57CT-04I/SS | PIC16F57-I/SS | PIC16C57C-20I/SS |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SSOP-28 | SSOP-28 - same | SSOP-28 - same | SSOP-28 - same | SSOP-28 - same |
| Program Memory | 3 KB OTP EPROM | 3 KB OTP EPROM | 3 KB OTP EPROM | 3 KB Flash | 3 KB OTP EPROM |
| Maximum Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 20 MHz | 20 MHz |
| Supply Voltage Range | 3.0 V to 6.25 V | 3.0 V to 6.25 V | 3.0 V to 6.25 V | 2.0 V to 5.5 V | 3.0 V to 6.25 V |
| Operating Temperature Range | 0C to +70C (commercial) | 0C to +70C (commercial) | -40C to +85C (industrial) | -40C to +85C (industrial) | -40C to +85C (industrial) |
| I/O Pins | 20 | 20 | 20 | 20 | 20 |
| Memory Type | OTP EPROM (one-time programmable) | OTP EPROM | OTP EPROM | Flash (reprogrammable) | OTP EPROM |
| Stack Depth | 2 levels (hardware) | 2 levels | 2 levels | 2 levels | 2 levels |
Key Differentiators
- 3 KB OTP program memory - largest in the PIC16C5X family (vs PIC16C56-RC/SS)
- RC oscillator grade characterized for low-cost RC timing (vs PIC16C57-XT/SS)
- Flash-based modernization path via PIC16F57 (vs PIC16F57-I/SS)
Design Notes
The PIC16C57-RC/SS operates from 3.0 V to 6.25 V with typical active current of about 2 mA at 5 V / 4 MHz and SLEEP current under 10 µA (per PIC16C5X datasheet). For battery-powered designs, use SLEEP aggressively: clear the watchdog flag, execute SLEEP, and let the watchdog timer (typical ~18 ms internal RC period) wake the device for periodic tasks. Decouple VDD with a 100 nF ceramic capacitor placed within 5 mm of the supply pins, and add a 10 µF bulk capacitor if the supply is shared with inductive loads (relays, motors).
Place the MCLR pull-up resistor (typically 10 kΩ) directly adjacent to the MCLR pin. If using an RC oscillator (this 'RC' grade), keep the R/C components within 1 cm of OSC1/CLKIN and OSC2/CLKOUT to avoid stray capacitance and EMI pickup. For noisy industrial environments, place a small ferrite bead or 10 Ω resistor in series with VDD close to the IC, and add a 100 nF + 10 µF decoupling pair. The 28-SSOP package has a 0.65 mm pitch and 5.30 mm body width - ensure your PCB footprint matches the standard SSOP-28 land pattern in IPC-7351.
The PIC16C57 has only a 2-level hardware stack, so deeply nested subroutine calls will overflow and cause unpredictable execution - keep call depth to 1 or 2 levels. Watchdog timer MUST be cleared in software within the watchdog timeout window (typically 18 ms) or it will reset the MCU; this is critical in long ISR routines. The OTP memory cannot be erased or rewritten, so firmware must be fully validated before programming the final parts. Programming requires a Microchip device programmer (PICSTART Plus, MPLAB PM3) or compatible third-party programmer.
Estimated: At 4 MHz the harmonic content is low, so signal integrity is rarely a concern, but route OSC traces over a continuous ground plane and avoid running high-current traces (relay drivers) parallel to oscillator traces for more than 5 mm. The 28-SSOP thermal pad is not present, so no special thermal relief is needed - typical junction-to-ambient resistance is ~100 C/W, well within safe limits at 4 MHz and 5 V. Leave 3 mm clearance around the IC for rework access and add a test-point land on MCLR for in-circuit debugging.
Compliance Information
RoHS and REACH compliance per Microchip product page. Not AEC-Q100 qualified (automotive grade); for AEC-Q100 designs choose a PIC16F-series automotive variant. Lead-free (Pb-free) reflow-compatible per JEDEC J-STD-020.
