PIC16C57-RCI/SS - 8-bit 3KB OTP MCU, 20 I/O, 28-SSOP | Microchip
MPN: PIC16C57-RCI/SS β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.33 | $5.33 |
| 10 | $4.95 | $49.50 |
| 100 | $4.42 | $442.00 |
| 500 | $3.95 | $1,975.00 |
| 1,000 | $3.5 | $3,500.00 |
PIC16C57-RCI/SS Overview
An 8-bit microcontroller (MCU) is a single-chip computer integrating an 8-bit CPU, program memory, data RAM, and peripheral I/O on one die. The PIC16C5X family sits at the low end of Microchip's PIC architecture hierarchy - beneath PIC12, PIC14, and the mid-range PIC16 enhanced core, but above simple 4-bit controllers. These MCUs serve as the embedded "brain" of systems where low cost, deterministic instruction execution, and easy programming outweigh the need for large memory or high-speed analog peripherals.
Key features of the PIC16C57 include a RISC instruction set of only 33 single-word instructions, a 12-bit wide instruction word for 2:1 code compression over competitive 8-bit MCUs, a hardware watchdog timer, an 8-bit real-time timer/counter, programmable code protection, and power-saving SLEEP mode. The device is fully static, allowing the clock to be stopped without losing register contents, and supports both RC and crystal/ceramic resonator oscillator configurations.
The architecture combines a Harvard bus (separate program and data memory paths) with a 2-stage pipeline, which is why most instructions execute in a single 200 ns cycle. This pipelined RISC core predates the more capable PIC16 enhanced mid-range family and is intended for straightforward control loops, sensor polling, and glue-logic replacement in cost-sensitive products.
Typical applications include consumer appliance controls, battery chargers, LED drivers, simple sensor interfaces, security panel keypads, and low-end remote controls. Industrial uses span small motor control boards, instrumentation front-ends, and user-interface modules where the 20 I/O pins and 3KB program memory are sufficient. The PIC16C57-RCI/SS in industrial (-40C to +85C) grade is a frequent choice for harsh-environment designs.
When designing with the PIC16C57, note that it lacks an on-chip debugger and in-circuit serial programming (ICSP) header support in the original 1990s silicon - modern debug requires a header and an emulator or ICE. For new designs, Microchip recommends the flash-based PIC16F57 successor with identical pinout but reprogrammable memory. This page synthesizes distributor pricing, pin-compatible SSOP alternatives, and design notes that go beyond the manufacturer datasheet.
Drop-in alternatives for PIC16C57-RCI/SS β 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-RCI/SS (same form factor and footprint) β differing in Program Memory Size, Package, Timers, Mounting Type, Program Memory Type.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F57-I/SS
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57-RCI/SP
β Drop-Inβ In Stock
$2.93 / Unit
View Datasheet βPIC16C57C-20/SS
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57C-20I/SS
β Drop-Inβ In Stock
$0.9 / Unit
View Datasheet βPIC16C57C-04I/SS
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57-RCI/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 8-bit RISC |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 3 KB (2K x 12) |
| RAM | 72 bytes |
| I/O Pins | 20 |
| Supply Voltage (VDD) | 3.0 V to 5.5 V |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns |
| Instruction Set Size | 33 single-word instructions |
| Instruction Word Width | 12 bits |
| Timers | 1 x 8-bit RTCC + WDT |
| Oscillator Modes | RC, Crystal, Ceramic Resonator |
| Package | 28-pin SSOP (0.209", 5.30 mm) |
| Operating Temperature | -40C to +85C (Industrial) |
| Mounting Type | Surface Mount |
| MSL Level | 1 |
| RoHS Status | Compliant |
| Lead-Free | Yes |
| Halogen-Free | Yes |
| ECC Code | EAR99 |
PIC16C57-RCI/SS Pin Configuration
| Pin 1 | RA2 β Bidirectional I/O port A bit 2 |
| Pin 2 | RA3 β Bidirectional I/O port A bit 3 |
| Pin 3 | RA4/RTCC β Bidirectional I/O / Timer clock input |
| Pin 4 | MCLR β Master Clear reset (active low) |
| Pin 5 | VSS β Ground reference |
| Pin 6 | RB0/INT β Bidirectional I/O / External interrupt |
| Pin 7 | RB1 β Bidirectional I/O port B bit 1 |
| Pin 8 | RB2 β Bidirectional I/O port B bit 2 |
| Pin 9 | RB3 β Bidirectional I/O port B bit 3 |
| Pin 10 | RB4 β Bidirectional I/O port B bit 4 |
| Pin 11 | RB5 β Bidirectional I/O port B bit 5 |
| Pin 12 | RB6 β Bidirectional I/O port B bit 6 |
| Pin 13 | RB7 β Bidirectional I/O port B bit 7 |
| Pin 14 | VSS β Ground reference |
| Pin 15 | OSC2/CLKOUT β Oscillator output / Clock out |
| Pin 16 | OSC1/CLKIN β Oscillator input / Clock in |
| Pin 17 | RC0 β Bidirectional I/O port C bit 0 |
| Pin 18 | RC1 β Bidirectional I/O port C bit 1 |
| Pin 19 | RC2 β Bidirectional I/O port C bit 2 |
| Pin 20 | RC3 β Bidirectional I/O port C bit 3 |
| Pin 21 | RC4 β Bidirectional I/O port C bit 4 |
| Pin 22 | RC5 β Bidirectional I/O port C bit 5 |
| Pin 23 | RC6 β Bidirectional I/O port C bit 6 |
| Pin 24 | RC7 β Bidirectional I/O port C bit 7 |
| Pin 25 | VSS β Ground reference |
| Pin 26 | VDD β Positive supply (3.0V to 5.5V) |
| Pin 27 | RA0 β Bidirectional I/O port A bit 0 |
| Pin 28 | RA1 β Bidirectional I/O port A bit 1 |
Typical Applications
PIC16C57-RCI/SS is suitable for 6 applications: Consumer Appliance Control, Battery Charger Controllers, LED Display Drivers and Lighting Controllers, Security Keypads and Access Control Panels, Sensor Interface and Data Acquisition Front-Ends, Remote Controls and IR/RF Transmitters.
Consumer Appliance Control
The PIC16C57-RCI/SS is well suited for cost-sensitive consumer appliance control boards, including microwave oven keypads, washing-machine front panels, and rice cooker controllers. Its 3KB OTP memory fits typical appliance state-machine firmware, while the 20 I/O pins directly drive 7-segment LED displays, key matrix scans, and triac-fired heater relays without external drivers. The 5 MIPS throughput at 20 MHz handles encoder pulse counting and sensor debouncing in real time, and the -40C to +85C industrial range survives kitchen and laundry environments where temperature swings and humidity are common. Power consumption in SLEEP mode is well under 1 mA, satisfying Energy Star standby targets. The 33-instruction RISC set keeps firmware development fast and inexpensive.
Recommended
Battery Charger Controllers
The PIC16C57-RCI/SS excels as the control brain in simple NiCd, NiMH, and SLA battery charger designs, where its 8-bit RTCC handles charge-time accumulation and its 20 I/O pins interface with current-sense amplifiers, status LEDs, and relay-controlled AC mains switching. The 3KB program memory stores charge profiles (trickle, bulk, absorption, float), and the 5 MIPS throughput supports delta-V peak detection algorithms for NiMH chemistries. Industrial temperature range allows the charger to operate in unheated garages or outdoor enclosures. Programmable code protection prevents firmware theft in consumer products. The OTP memory is acceptable because the firmware is mature and unchanging, keeping the BOM cost low versus flash-MCU alternatives.
Recommended
LED Display Drivers and Lighting Controllers
The PIC16C57-RCI/SS is widely used in LED sign controllers, marquee displays, and decorative lighting strips, where its 20 I/O pins can Charlieplex or matrix-multiplex up to 64 LEDs at high refresh rates without flicker. The 200 ns instruction cycle supports 1 kHz PWM dimming across multiple channels, allowing smooth brightness gradients and color mixing in RGB fixtures. The 3KB OTP memory holds 8 to 16 animation patterns and lookup tables for gamma correction. Industrial temperature operation suits outdoor architectural lighting. The 33-instruction set keeps LED-control firmware small and fast to develop. The 28-SSOP package is small enough for inline placement in light-strip modules.
Recommended
Security Keypads and Access Control Panels
The PIC16C57-RCI/SS serves as the main controller in alarm keypads, door-access panels, and simple RFID readers, with its 20 I/O pins scanning 4x4 key matrices, driving piezo buzzers, and reading Wiegand-format card inputs. The 3KB OTP memory fits PIN validation, lockout timers, and EEPROM emulation routines for credential storage. Hardware watchdog timer prevents lockup if RF noise corrupts program flow, an essential feature for unattended security devices. The industrial temperature range handles outdoor gate-control boxes in cold climates. Code protection bits prevent reverse engineering of the access-control firmware. Programmable brown-out reset ensures clean startup after power dips from nearby motor loads.
Recommended
Sensor Interface and Data Acquisition Front-Ends
The PIC16C57-RCI/SS is well matched to compact sensor-interface modules reading thermistors, photodiodes, flow meters, and strain gauges, where the on-chip 8-bit RTCC times sample intervals and the 20 I/O bits handle digital sensor interfaces and isolated serial uplinks. The 5 MIPS throughput allows polled or interrupt-driven sensor reads at 1 kHz without missing events, and the 3KB OTP memory fits calibration tables and linearization polynomials. Industrial temperature range suits outdoor weather stations and process-control cabinets. The fully static clock can be slowed to 32 kHz for ultra-low-power battery-operated data loggers. Programmable code protection secures calibration data against field tampering.
Recommended
Remote Controls and IR/RF Transmitters
The PIC16C57-RCI/SS is a classic choice for universal remote controls, garage-door openers, and 433 MHz RF transmitters, where its 20 I/O pins scan 6x4 key matrices, drive IR LEDs via PWM, and bit-bang simple OOK/FSK RF protocols. The 3KB OTP memory holds 200 to 500 device codes plus macro definitions. The 200 ns instruction cycle allows precise 38 kHz carrier generation for IR consumer protocols (RC5, NEC, SIRC). The 33-instruction set keeps development of timing-critical encoders simple. Industrial temperature range handles outdoor garage-door keypads in winter. Low SLEEP-mode current extends battery life to a year or more in typical use.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57-RCI/SS β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F57-I/SS | PIC16C57-RCI/SP | PIC16C57C-20/SS | PIC16C57C-20I/SS | PIC16C57C-04I/SS |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP (5.30 mm) | 28-SSOP - same | 28-SPDIP (through-hole) | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same |
| Program Memory Type | 3 KB OTP EPROM | 3 KB Flash | 3 KB OTP EPROM | 3 KB OTP EPROM | 3 KB OTP EPROM | 3 KB OTP EPROM |
| Program Memory Size | 3 KB (2K x 12) | 3 KB | 3 KB | 3 KB | 3 KB | 3 KB |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 4 MHz |
| Supply Voltage Range | 3.0 V to 5.5 V | 2.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C | -40C to +85C | 0C to +70C (Commercial) | -40C to +85C | -40C to +85C |
| ICSP (In-Circuit Serial Programming) | No (OTP only) | Yes | No | No | No | No |
Key Differentiators
- Flash reprogrammability with same pinout (vs PIC16F57-I/SS)
- 20 MHz throughput for timing-sensitive encoders (vs PIC16C57C-04I/SS)
- Industrial -40C to +85C temperature range (vs PIC16C57C-20/SS)
Design Notes
Estimated: at VDD = 5.0 V and 20 MHz clock, the PIC16C57-RCI/SS typical operating current is approximately 5 mA (25 mW). Add a 0.1 uF decoupling capacitor within 5 mm of the VDD pin (pin 26) and a bulk 10 uF tantalum or ceramic capacitor near the supply input. A second VSS pin (pin 14) is provided for low-inductance ground return; both VSS pins must be connected to a continuous ground plane. The brown-out reset is not present on the original PIC16C57 silicon, so use an external reset supervisor such as MCP100 or MCP809 if VDD rise time is unpredictable in your design.
For the 28-SSOP package, route all 20 I/O traces on the top layer only - the 0.65 mm pitch is too fine for reliable through-via fan-out. Use 0.15 mm (6 mil) trace width with 0.15 mm spacing to maintain 50 ohm characteristic impedance for high-speed signals. Place the decoupling capacitor as close as possible to the VDD pin with a via directly to the ground plane. The 28-SSOP thermal pad is not present on this part; the small die dissipates less than 100 mW, so thermal copper pours are optional. A ground island around the crystal/oscillator traces (with the OSC1/OSC2 guarded by a grounded trace) reduces EMI pickup by 6 to 10 dB.
Avoid using the MCLR pin as a general input - the PIC16C57 lacks internal weak pull-up on MCLR, so it must be tied to VDD through a 10 kohm resistor for normal operation. Do not leave OSC1 floating in RC mode, or the device will draw excessive current. The CONFIG word must be set explicitly (CP off, WDT on/off, RC/HS/LP oscillator selection) or the device will not start. The PIC16C57 has no ICSP, so plan for socketed programming or a device programmer (MPLAB PM3). For new designs, strongly consider the flash-based PIC16F57 with identical pinout to avoid OTP programming risk during prototype bring-up.
Compliance Information
RoHS and REACH compliant per Microchip product page. Halogen-free per GlobalSpec datasheet. ECCN EAR99. Not AEC-Q100 qualified; for automotive applications consult Microchip's PIC16 enhanced automotive family.
