PIC16C57C-20/SO - 8-Bit 20MHz 3KB OTP MCU | Microchip
MPN: PIC16C57C-20/SO β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.2 | $4.20 |
| 10 | $3.85 | $38.50 |
| 100 | $3.52 | $352.00 |
| 500 | $3.18 | $1,590.00 |
| 1,000 | $2.89 | $2,890.00 |
PIC16C57C-20/SO Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory (ROM/OTP/Flash), data RAM, and integrated peripherals. Within the broader hierarchy, microcontrollers belong to the embedded computing family, which also includes microprocessors, DSPs, and SoCs. The PIC16C5X family occupies the entry-level 8-bit RISC position in Microchip's portfolio, sitting below the PIC16F (Flash), PIC18 (enhanced 8-bit), and dsPIC (16-bit DSC) families. One-time-programmable (OTP) EPROM-based MCUs like the PIC16C57C are designed for high-volume production where firmware is finalized and field-reprogramming is not required.
Key features of the PIC16C57C-20/SO include a fully static CMOS design supporting DC to 20MHz operation, 8-bit data width with 12-bit instruction width, 72 bytes of general-purpose RAM, a watchdog timer for reliable operation, a power-on reset circuit, and a code-protection feature for firmware security. The 28-SOIC package is suitable for surface-mount assembly in volume manufacturing, and the device is widely adapted for automotive, industrial, and consumer applications.
Architecturally, the PIC16C57C uses a Harvard-style memory architecture with separate program and data paths. The 12-bit instruction word enables direct addressing of the full 2K x 12 program memory without paging, while the RISC instruction set keeps most operations single-cycle. This combination delivers deterministic interrupt latency and a compact code footprint.
Typical applications include automotive subsystems, industrial controllers, appliance control, security panels, and consumer electronics that benefit from the proven PIC architecture and the low unit cost of OTP memory. The 20 I/O pins make it suitable for keyboard scanning, LED driving, relay control, and simple sensor interfaces. When designing with this part, note that OTP memory cannot be rewritten after programming - the device is intended for production designs where firmware is fully validated before mask programming. Use the JW windowed variant for engineering development.
Drop-in alternatives for PIC16C57C-20/SO 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 PIC16C57C-20/SO (same form factor and footprint) β differing in Program Memory Type, Package, Core Architecture, Program Memory Size, Watchdog Timer.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C57C-20I/SO
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$3.62 / Unit
View Datasheet βPIC16C57C-04/SO
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
PIC16C56-20/SO
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
PIC16C55-20/SO
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
PIC16C57C-20I/SP
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$1.85 / Unit
View Datasheet βPIC16C57C-20/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC RISC |
| Family | PIC16C5X |
| Program Memory Type | OTP (One-Time-Programmable EPROM) |
| Program Memory Size | 3 KB (2K x 12) |
| RAM | 72 bytes |
| Maximum CPU Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns (at 20 MHz) |
| Number of Instructions | 33 (single-word, single-cycle) |
| Instruction Width | 12 bits |
| I/O Pins | 20 |
| Timers | Watchdog Timer (WDT) |
| Package | 28-pin SOIC (0.295", 7.50mm width) |
| Mounting Type | Surface Mount |
| Operating Temperature | 0C to +70C (commercial) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
| MSL Level | 1 |
| Data EEPROM | Not present (none on PIC16C57C) |
| ADC | None (no on-chip ADC) |
| ICSP | Not supported (OTP device) |
PIC16C57C-20/SO Pin Configuration
| Pin 1 | RA0 β Bidirectional I/O Port A bit 0 |
| Pin 2 | RA1 β Bidirectional I/O Port A bit 1 |
| Pin 3 | RA2 β Bidirectional I/O Port A bit 2 |
| Pin 4 | RA3 β Bidirectional I/O Port A bit 3 |
| Pin 5 | VDD β Positive supply voltage (3.0V to 6.25V) |
| Pin 6 | VSS β Ground reference |
| Pin 7 | OSC1 β Oscillator input / external clock input |
| Pin 8 | OSC2 β Oscillator output (crystal mode) |
| Pin 9 | MCLR β Master Clear reset input (active low) |
| Pin 10 | RTCC β Real-Time Clock/Counter external I/O |
| Pin 11 | RB0 β Bidirectional I/O Port B bit 0 |
| Pin 12 | RB1 β Bidirectional I/O Port B bit 1 |
| Pin 13 | RB2 β Bidirectional I/O Port B bit 2 |
| Pin 14 | RB3 β Bidirectional I/O Port B bit 3 |
| Pin 15 | RB4 β Bidirectional I/O Port B bit 4 |
| Pin 16 | RB5 β Bidirectional I/O Port B bit 5 |
| Pin 17 | RB6 β Bidirectional I/O Port B bit 6 |
| Pin 18 | RB7 β Bidirectional I/O Port B bit 7 |
| Pin 19 | RC0 β Bidirectional I/O Port C bit 0 |
| Pin 20 | RC1 β Bidirectional I/O Port C bit 1 |
| Pin 21 | RC2 β Bidirectional I/O Port C bit 2 |
| Pin 22 | RC3 β Bidirectional I/O Port C bit 3 |
| Pin 23 | RC4 β Bidirectional I/O Port C bit 4 |
| Pin 24 | RC5 β Bidirectional I/O Port C bit 5 |
| Pin 25 | RC6 β Bidirectional I/O Port C bit 6 |
| Pin 26 | RC7 β Bidirectional I/O Port C bit 7 |
| Pin 27 | NC β Not connected (reserved) |
| Pin 28 | NC β Not connected (reserved) |
Typical Applications
PIC16C57C-20/SO is suitable for 7 applications: Automotive Body Control Modules, Industrial Control Panels, Consumer Appliance Controllers, Security and Alarm Panels, Remote Control and IR Transmitters, Sensor Interface Modules, Toys and Hobby Electronics.
Automotive Body Control Modules
The PIC16C57C-20/SO fits automotive body controllers because its 20MHz CPU, 3KB OTP, and 20 I/O pins deliver deterministic real-time response in a small surface-mount package. The 33-instruction RISC core executes 5 MIPS, enabling multiplexed switch scanning and PWM drive for lighting and accessory loads without an RTOS. The 28-SOIC footprint supports high-volume SMT assembly, and Microchip's long-term automotive pedigree provides the supply-chain stability required for 7-10 year vehicle production runs.
Recommended
Industrial Control Panels
In industrial control panels the PIC16C57C-20/SO drives relay outputs, scans key matrices, and handles simple serial links while operating from the same 5V rail that powers the I/O. The 20 I/O pins handle up to 20 inputs or outputs directly, including 25mA sink capability for relay coils and LED indicators. The OTP memory locks the validated PLC ladder logic into silicon, eliminating firmware tampering or accidental erasure in the field. The 28-SOIC package suits DIN-rail PCB assemblies where vibration resistance matters.
Recommended
Consumer Appliance Controllers
The PIC16C57C-20/SO serves as the main controller in white goods such as washing machines, microwave ovens, and dishwashers where cost-per-unit is paramount. The 3KB OTP stores the appliance state machine and user-interface logic, and 20 I/O lines interface directly to keypads, seven-segment displays, triac-fired loads, and sensors. The PIC RISC architecture's deterministic timing makes time-based sequences (soak, wash, rinse) reliable without an RTOS. The 28-SOIC is compatible with pick-and-place assembly lines.
Recommended
Security and Alarm Panels
The PIC16C57C-20/SO is well suited to security alarm panels that monitor multiple zones and drive sirens, dialers, and keypads from a single 5V supply. The 20 I/O lines accept up to 20 normally-closed loop inputs and drive status LEDs and piezo buzzers directly. The watchdog timer and code-protection feature protect against firmware tampering, critical for security certification. The OTP memory locks the configuration, preventing field reverse engineering of the alarm protocol.
Recommended
Remote Control and IR Transmitters
Handheld IR remote controls benefit from the PIC16C57C-20/SO's low cost, low power, and ability to handle RC5/RC6/SIRC encoding algorithms directly in firmware. The 3KB OTP holds the full command set for TVs, set-top boxes, and consumer A/V equipment, and the static CMOS core allows oscillator-gated sleep for months of battery life from two AA cells. The 28-SOIC's small footprint fits within slim handset enclosures. The 20MHz clock delivers precise carrier-frequency timing for IR emission.
Recommended
Sensor Interface Modules
The PIC16C57C-20/SO works as a sensor-conditioning front end for low-bandwidth analog sensors, digitizing readings with an external ADC or comparator and outputting the data over UART or SPI to a host processor. The 20 I/O lines accept digital sensors, address switches, and status LEDs while freeing the host MCU from polling tasks. The 5V operating range matches industrial transducer rails. The OTP memory ensures the calibration coefficients are locked at production, providing traceability and tamper resistance.
Recommended
Toys and Hobby Electronics
Cost-sensitive toys, model train controllers, and educational kits use the PIC16C57C-20/SO because its unit price drops below USD 3 in volume and its 33-instruction set is easy to teach in school curricula. The 3KB OTP stores motion sequences, sound patterns, and I/O multiplexing logic. The 20 I/O lines drive hobby servos, LEDs, and small DC motors directly when paired with transistors. The 28-SOIC fits small enclosures and the Microchip development toolchain (MPLAB) supports in-circuit programming via the JW windowed variant.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57C-20/SO β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C57C-20I/SO | PIC16C57C-04/SO | PIC16C56-20/SO | PIC16C55-20/SO |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (0.295") | 28-SOIC (0.295") - same | 28-SOIC (0.295") - same | 28-SOIC (0.295") - same | 28-SOIC (0.295") - same |
| Program Memory | 3 KB OTP (2K x 12) | 3 KB OTP | 3 KB OTP | 1 KB OTP (1K x 12) | 768 B OTP (512 x 12) |
| RAM | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 24 bytes |
| Max Clock Speed | 20 MHz | 20 MHz | 4 MHz | 20 MHz | 20 MHz |
| I/O Pins | 20 | 20 | 20 | 12 | 20 |
| Operating Temperature | 0C to +70C (commercial) | -40C to +85C (industrial) | 0C to +70C (commercial) | 0C to +70C (commercial) | 0C to +70C (commercial) |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM |
| Supply Voltage | 3.0V to 6.25V | 3.0V to 6.25V | 3.0V to 6.25V | 3.0V to 6.25V | 3.0V to 6.25V |
| RoHS / Lead-Free | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes |
Key Differentiators
- Largest OTP memory in PIC16C5X family (vs PIC16C56-20/SO)
- Full 20 I/O pins (vs PIC16C56-20/SO)
- 20MHz speed grade for time-critical loops (vs PIC16C57C-04/SO)
- Standard commercial temperature for indoor designs (vs PIC16C57C-20I/SO)
Design Notes
Decouple VDD (pin 5) with a 0.1uF ceramic capacitor placed within 5mm of the package and a 10uF tantalum or aluminum bulk capacitor at the board entry point. The PIC16C57C has no internal brown-out detector, so VDD must remain within the 3.0V-6.25V operating range under all load transients. For noisy 24V industrial environments, add a 5V LDO (MCP1700) in front of the MCU rather than relying on a resistive divider, because the PIC16C57C does not regulate its own supply.
Route the 20MHz crystal traces (OSC1 pin 7 and OSC2 pin 8) as short and symmetric as possible, with the crystal can grounded on both ends and placed within 10mm of the MCU. Add a ground guard ring around the crystal and keep digital signal traces at least 3mm away to prevent radiated coupling. For the 28-SOIC footprint, use 0.5mm-wide SOIC land pads with exposed solder fillets to facilitate visual inspection of reflow joints.
Do not confuse the OTP PIC16C57C with the Flash PIC16F57 - the C suffix means EPROM one-time-programmable. Once programmed, OTP memory cannot be erased or rewritten, so always use the JW windowed variant (PIC16C57C/JW) or the PIC16F57-I/SO Flash part during development. The 28-SOIC pinout is identical between PIC16C57C and PIC16F57, but the configuration bits, memory map, and programming protocol differ; firmware binaries are NOT portable.
The PIC16C57C-20/SO I/O pins have 25mA sink/source capability, but total package current is limited to 200mA across all pins combined (100mA per port). When driving multiple high-current loads (LEDs, relays, optocouplers), distribute the load across ports to stay within the per-port 100mA budget. Excessive current on one port while the others are quiescent can cause internal ground-bounce and unreliable I/O reads on adjacent pins.
Compliance Information
RoHS compliant and lead-free per Microchip product documentation. Not AEC-Q100 qualified; for automotive AEC-Q100 applications, use the PIC16C57C-20E/SO extended temperature variant and verify with Microchip automotive qualification documentation. Halogen-free status not explicitly stated in provided data; check Microchip compliance certificate.
