PIC16C56-RCE/SO - 8-Bit 4MHz OTP MCU 1.5KB | Microchip
MPN: PIC16C56-RCE/SO ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.1 | $3.10 |
| 10 | $2.85 | $28.50 |
| 100 | $2.4 | $240.00 |
| 500 | $2.1 | $1,050.00 |
| 1,000 | $1.85 | $1,850.00 |
PIC16C56-RCE/SO Overview
An 8-bit microcontroller (MCU) is a single-chip computer built around an 8-bit data path, on-chip program memory, RAM, and integrated peripherals such as timers, reset circuitry, and I/O ports. MCUs sit within the broader hierarchy: microcontroller -> embedded processor -> semiconductor device -> integrated circuit. The PIC16C5X family is Microchip's foundational baseline architecture using 12-bit-wide instructions and a Harvard memory layout, delivering roughly 2:1 code compression over competitive 8-bit MCUs of its era. Because PIC16C56 OTP parts can be programmed exactly once, they are aimed at high-volume production where code is fixed and firmware field updates are not required.
Key features of the PIC16C56-RCE/SO include a 3.25 V to 6.0 V single-supply range, an extended operating temperature window of -40 C to +125 C, fully static CMOS design for low quiescent current, and a 4 MHz maximum external clock rate that yields an instruction cycle of 1 microsecond (one-quarter of the oscillator period, four clocks per instruction). The SO package variant supports surface-mount assembly on standard reflow profiles, while the same die is also offered in PDIP and windowed CERDIP for development.
Architecturally, the device uses a RISC-style instruction set with 33 single-word/12-bit instructions, a two-level deep hardware stack, and dedicated SFRs for I/O and configuration. Configuration is performed by programming bits that select oscillator type, WDT enable, code protection, and brown-out options.
Typical applications include industrial automation controllers, simple consumer appliances, automotive body and chassis subsystems, replacement of discrete logic in glue-logic designs, and remote sensor transmitters. Designers most often choose this device when the BOM must remain below one dollar and the firmware is stable across the product lifecycle.
When designing with PIC16C56-RCE/SO, plan for programming before final assembly: OTP parts cannot be reprogrammed in-circuit, so a parallel programming socket or gang programmer is required. Validate brown-out and WDT behavior across the full -40 C to +125 C operating window, and add bulk capacitance on VDD if the application drives heavy transient loads.
This page consolidates verified distributor pricing, drop-in alternatives from the PIC16C5X family, and practical engineering notes that are not gathered together on any single manufacturer or distributor page.
Drop-in alternatives for PIC16C56-RCE/SO — 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 PIC16C56-RCE/SO (same form factor and footprint) — differing in Package, Core Architecture, Oscillator Type, Program Memory Size, Program Memory Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C56-RCI/SO
✅ Drop-In✓ In Stock
$0.99 / Unit
View Datasheet →PIC16C56A-04/SO
✅ Drop-In✓ In Stock
$1.4 / Unit
View Datasheet →PIC16F57-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C56T-RCE/SO
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.16 / Unit
View Datasheet →PIC16C56-HSI/SO
✅ Drop-In✓ In Stock
$1.83 / Unit
View Datasheet →PIC16C56-LPI/SO
✅ Drop-In✓ In Stock
$1.31 / Unit
View Datasheet →PIC16C56-RCE/SO Maximum Ratings & Electrical Characteristics
| Core Processor | PIC |
| Core Size | 8-Bit |
| Maximum Clock Frequency | 4 MHz |
| Program Memory Size | 1.5 KB (1K x 12) |
| Program Memory Type | OTP (One-Time Programmable EPROM) |
| RAM Size | 25 x 8 bytes |
| EEPROM Size | None |
| Number of I/O Pins | 12 |
| Supply Voltage (Vcc/Vdd) | 3.25 V to 6.0 V |
| Oscillator Type | External |
| Peripherals | POR, WDT |
| Connectivity | None (no UART/SPI/I2C) |
| Operating Temperature | -40 C to +125 C |
| Package | 18-SOIC (0.295", 7.50 mm width) |
| Mounting Type | Surface Mount |
| Instruction Set Width | 12-bit |
| Number of Instructions | 33 |
| Hardware Stack Depth | 2 levels |
| RoHS Status | Non-Compliant (legacy) |
PIC16C56-RCE/SO Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O port A bit 2 |
| Pin 2 | RA3 — Bidirectional I/O port A bit 3 |
| Pin 3 | RTCC — Real-Time Clock/Counter input or I/O |
| Pin 4 | MCLR — Master Clear reset input (active low) |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0 — Bidirectional I/O port B bit 0 |
| Pin 7 | RB1 — Bidirectional I/O port B bit 1 |
| Pin 8 | RB2 — Bidirectional I/O port B bit 2 |
| Pin 9 | RB3 — Bidirectional I/O port B bit 3 |
| Pin 10 | RB4 — Bidirectional I/O port B bit 4 |
| Pin 11 | RB5 — Bidirectional I/O port B bit 5 |
| Pin 12 | RB6 — Bidirectional I/O port B bit 6 |
| Pin 13 | RB7 — Bidirectional I/O port B bit 7 |
| Pin 14 | VDD — Positive supply voltage 3.25V to 6.0V |
| Pin 15 | OSC2 — Oscillator crystal/ceramic resonator output |
| Pin 16 | OSC1 — Oscillator crystal/ceramic resonator input or external clock |
| Pin 17 | RA0 — Bidirectional I/O port A bit 0 |
| Pin 18 | RA1 — Bidirectional I/O port A bit 1 |
Typical Applications
PIC16C56-RCE/SO is suitable for 6 applications: Industrial Automation Controllers, Consumer Appliance Control, Automotive Body and Chassis Electronics, Glue-Logic Replacement Designs, Remote Sensor Transmitters, Simple Consumer Toys and Hobby Electronics.
Industrial Automation Controllers
The PIC16C56-RCE/SO is widely deployed in industrial automation for simple closed-loop control tasks such as conveyor sorting, valve sequencing, and small motor start-stop logic. Its 1.5 KB OTP program memory holds typical ladder-replacement state machines (8-12 I/O, 25 bytes RAM, WDT-protected execution), while the -40 C to +125 C operating range covers both cabinet-internal and field-edge installations. The 3.25 V to 6.0 V supply aligns with 5 V regulated industrial rails, and the external oscillator allows precise timing for deterministic response. Compared with discrete 74HC logic, this MCU reduces PCB area by 60-70 percent while adding reprogrammability for prototype stages (flash derivatives such as PIC16F57-I/SO). Designers should add a bulk 10 uF decoupling capacitor and use POR plus WDT together to recover from brown-out events that occur during motor inrush.
Recommended
Consumer Appliance Control
In consumer appliances such as coffee makers, microwave ovens, washing machines, and air purifiers, the PIC16C56-RCE/SO replaces mechanical timers and cam switches with software-defined sequences. Its 1.5 KB OTP stores typical wash-cycle or brew-profile state machines, and the 12 I/O drive seven-segment displays, keypads, triac interfaces, and solenoid valves directly. The 4 MHz clock and 1 MIPS throughput comfortably handle debounced keypad scanning, PWM buzzer tones, and triac zero-cross synchronization. Compared with legacy 4000-series CMOS logic, this MCU cuts component count from 8-12 discrete packages to a single SOIC-18, reducing both assembly cost and field failure rate. For high-volume SKUs, the OTP architecture ensures the firmware cannot be copied or modified after programming, providing IP protection. Designers should use MOVs across the AC-line-coupled triac drivers and observe ESD precautions on user-facing keypad inputs.
Recommended
Automotive Body and Chassis Electronics
The PIC16C56-RCE/SO serves in non-safety automotive subsystems such as interior lighting controllers, seat-position memories, mirror-fold actuators, and accessory multiplexers. Its -40 C to +125 C operating range, 5 V supply tolerance for load-dump transients (with external TVS protection), and external oscillator for EMI-immune clocking make it suitable for under-dash and door-module placements. The 1.5 KB OTP holds simple fault-tolerant state machines, and the 12 I/O drive relays, LEDs, and LIN-bus transceivers indirectly. Compared with full AEC-Q100-qualified microcontrollers, this part is typically used in cost-sensitive body applications where the OEM accepts commercial-grade components with downstream qualification. For new automotive designs, designers should migrate to PIC16F57-I/SO or PIC16F18313-I/SN, both of which are AEC-Q100 qualified and offer enhanced peripherals. Always add reverse-battery, load-dump, and jump-start protection on the VDD rail.
Recommended
Glue-Logic Replacement Designs
The PIC16C56-RCE/SO is a classic glue-logic replacement where designers substitute discrete 74HC00, 74LS138, and 74LS373 packages with a single programmable MCU. The 12 I/O pins emulate up to four 14-pin or two 20-pin SSI/MSI packages, while the 1.5 KB OTP stores lookup tables and conditional logic. Compared with discrete logic, this approach reduces PCB area, eliminates propagation-delay skew between gates, and allows late-stage feature additions by re-OTP programming. The 4 MHz clock is sufficient for debounced switch inputs, multiplexed LED matrices, and keypad scanners running at 1 ms intervals. Designers should retain a parallel programming footprint on the PCB so the OTP can be programmed before final assembly, and ensure unused I/O pins are configured as outputs to minimize quiescent current draw across the full -40 C to +125 C range.
Recommended
Remote Sensor Transmitters
In remote wireless sensor nodes for HVAC, agriculture, and building-automation telemetry, the PIC16C56-RCE/SO serves as a low-cost supervisory MCU that wakes on a timer, reads a sensor, and triggers a low-power radio such as the RFM69 or LoRa transceiver. The 1.5 KB OTP holds the sensor-conditioning state machine, and the 12 I/O drive the SPI radio interface plus several analog switches. Compared with 32-bit ARM Cortex-M0 alternatives, this PIC16C5X part draws under 1 mA active and supports slower clocks for battery-life extension. The -40 C to +125 C operating range covers outdoor agricultural and rooftop deployments. Designers should size the battery for a 10-year service life, add a load-sharing circuit between primary cells and a small supercap, and use the WDT to recover from RF command timeouts. Migration to PIC16F57-I/SO is recommended for new designs requiring firmware updates.
Recommended
Simple Consumer Toys and Hobby Electronics
The PIC16C56-RCE/SO powers low-cost consumer toys, educational electronics kits, and hobbyist microcontroller trainers where the price target must remain below 1 USD per node. Its 1.5 KB OTP stores pre-programmed behaviours such as LED chasers, sound effects, and motor sequences. The 12 I/O drive LEDs, buzzers, and small DC motors directly through driver transistors. Compared with the Arduino Uno's ATmega328P, this PIC16C5X part costs a fraction of the price at high volumes while offering adequate performance for non-real-time hobby projects. Designers can use the MPLAB PM3 universal programmer to write the OTP memory in production. For new hobbyist designs, migration to PIC16F57-I/SO is recommended because it allows in-circuit serial programming through the ICSP pins, eliminating the need for a parallel programmer. Always include a 100 nF decoupling capacitor close to VDD.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C56-RCE/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C56-RCI/SO | PIC16C56A-04/SO | PIC16F57-I/SO | PIC16C56T-RCE/SO | PIC16C56-HSI/SO | PIC16C56-LPI/SO |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same |
| Program Memory | 1.5 KB OTP | 1.5 KB OTP | 1.5 KB OTP | 3 KB Flash (+100%) | 1.5 KB OTP | 1.5 KB OTP | 1.5 KB OTP |
| Maximum Clock | 4 MHz | 4 MHz | 4 MHz | 20 MHz (+400%) | 4 MHz | 20 MHz (+400%) | 4 MHz |
| Operating Temperature | -40 C to +125 C (extended) | 0 C to +70 C (industrial) | -40 C to +125 C (extended) | -40 C to +85 C (industrial) | -40 C to +125 C (extended) | 0 C to +70 C (industrial) | 0 C to +70 C (industrial) |
| Supply Voltage | 3.25 V to 6.0 V | 3.25 V to 6.0 V | 3.0 V to 6.0 V | 2.0 V to 5.5 V (wider) | 3.25 V to 6.0 V | 3.25 V to 6.0 V | 2.5 V to 6.0 V (wider) |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | Flash (reprogrammable) | OTP EPROM | OTP EPROM | OTP EPROM |
| I/O Pins | 12 | 12 | 12 | 16 (+33%) | 12 | 12 | 12 |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Active | Obsolete | Obsolete | Obsolete |
| RoHS Compliance | Non-Compliant | Non-Compliant | Non-Compliant | Compliant | Non-Compliant | Non-Compliant | Non-Compliant |
Key Differentiators
- Only 18-SOIC PIC16C5X variant with extended -40C to +125C OTP and 4 MHz clock at current distributor stock (vs PIC16C56-RCI/SO)
- Drop-in flash-based migration available without PCB redesign (vs PIC16C56A-04/SO)
- Highest-temperature PIC16C5X option among 18-SOIC OTP variants (vs PIC16C56-LPI/SO)
Design Notes
PIC16C56-RCE/SO operates from 3.25 V to 6.0 V and draws less than 2 mA active at 4 MHz with all I/O switching. Place a 100 nF ceramic decoupling capacitor within 5 mm of the VDD pin, and add a 10 uF bulk capacitor if the supply traces run longer than 50 mm. For battery-powered designs, use the SLEEP instruction and wake via WDT or RTCC overflow to drop quiescent current below 4 uA; verify the brown-out reset threshold by sweeping VDD down at 0.1 V/ms because OTP-configured BOR has wide tolerance across temperature.
PIC16C56-RCE/SO is OTP (one-time programmable); code cannot be erased or rewritten once programmed. Always program a known-good firmware image using the MPLAB PM3 universal programmer before final PCB assembly, and use the windowed CERDIP PIC16C56/JW for development. A common mistake is configuring the MCLR pin as an input without an external pull-up; this causes intermittent POR failures because MCLR floats below the Vih threshold during VDD ramp-up. Always tie MCLR to VDD through a 10 kohm resistor, and add a 100 nF cap on MCLR only if in-circuit programming is required.
At -40 C to +125 C operation, thermal considerations shift from junction heating to oscillator startup margin. At the low end, crystals can take 100-200 ms to start; software should include a startup delay before initializing peripherals. At the high end, the PIC16C56-RCE/SO draws approximately 5 mA active, dissipating 25-30 mW at 5 V - well within the SOIC-18 theta-JA of approximately 80 C/W, so no heatsinking is required. Always characterize oscillator drift across the full temperature range and avoid relying on RTCC accuracy better than +/-5 percent without calibration.
The 18-SOIC package has a 0.295 inch (7.50 mm) body width, suitable for standard 8-mil-pitch SOIC land patterns. Keep all I/O traces shorter than 50 mm to avoid ringing on rising edges, and route the OSC1/OSC2 traces as a differential pair with a ground guard on both sides because the external clock waveform is sensitive to capacitive loading. Place the decoupling capacitor on the same layer as the MCU with a wide VDD trace; vias to internal power planes add parasitic inductance that can cause VDD droop during I/O transitions. Reserve a 6-pin ICSP header footprint on prototypes to allow field firmware updates via the PIC16F57-I/SO migration path.
Compliance Information
PIC16C56-RCE/SO predates the lead-free transition and is marked non-RoHS on distributor datasheets. Not AEC-Q100 qualified; PIC16F57-I/SO is the preferred AEC-Q100 alternative for automotive designs. REACH compliance confirmed via Microchip product declarations.