PIC16C56T-RCE/SS - 8-Bit 4MHz OTP MCU 1.5KB | Microchip
MPN: PIC16C56T-RCE/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.66 | $16.60 |
| 100 | $1.48 | $148.00 |
| 500 | $1.32 | $660.00 |
| 1,000 | $1.18 | $1,180.00 |
PIC16C56T-RCE/SS Overview
A microcontroller (MCU) is a single-chip computer that contains a CPU core, program memory, data memory, and integrated peripherals such as timers, reset circuits, and I/O. PIC® 16C microcontrollers belong to the original OTP/EPROM-based family of Microchip's 8-bit RISC architecture, sitting in the hierarchy: PIC16C5x -> 8-bit PIC MCU -> microcontroller -> embedded processor. They are widely used in cost-sensitive, low-power, deterministic control applications where flash reprogrammability is not required.
Key features include 33 single-word/single-cycle RISC instructions, 8-bit timer/counter with 8-bit programmable prescaler, Power-On Reset (POR), Watchdog Timer (WDT) with on-chip RC oscillator, and code protection. The RISC Harvard bus architecture achieves an instruction execution rate close to one instruction per clock cycle, with 2 MHz oscillator input producing a 1 µs instruction cycle.
The PIC16C56T-RCE/SS uses CMOS EPROM technology for the program memory and static RAM for data. The 'T' suffix indicates tape-and-reel packaging, 'RC' denotes the 4MHz RC-oscillator-based clock mode with extended temperature range, and 'E' specifies the industrial -40°C to +125°C operating range. The 20-SSOP package provides compact surface-mount integration.
Typical applications include automotive body controllers, appliance control boards, security-system keypads, low-end remote controls, and industrial sensor interfaces. Its wide operating voltage and temperature range make it suitable for harsh-environment embedded designs.
When designing with this device, note that OTP memory cannot be re-programmed - firmware bugs require replacement of the MCU. The on-chip WDT must be enabled in firmware and periodically cleared to recover from software lockups, and unused I/O pins should be configured as outputs to minimize quiescent current.
This page synthesizes distributor pricing, drop-in same-package alternatives from the PIC16C5x family, and practical design notes not consolidated on the manufacturer datasheet.
Drop-in alternatives for PIC16C56T-RCE/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 PIC16C56T-RCE/SS (same form factor and footprint) — differing in Package, Program Memory Size, Program Memory Type, RAM Size, Instruction Set.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C56T-10E/SS
✅ Drop-In✓ In Stock
$1.42 / Unit
View Datasheet →PIC16C56T-RCI/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C56T-RC/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C55T-RCE/SS
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC16C57C-RCE/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C56T-RCE/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC RISC |
| Program Memory Type | OTP (One-Time Programmable) EPROM |
| Program Memory Size | 1.5 KB (1K x 12) |
| RAM Size | 25 bytes |
| Maximum Clock Frequency | 4 MHz |
| Instruction Set | 33 single-word/single-cycle instructions |
| Supply Voltage Range | 3.25 V to 6 V |
| I/O Pins | 12 |
| Timers | 1 x 8-bit Timer/Counter with programmable prescaler |
| Package | 20-SSOP (0.209 inch / 5.30 mm width) |
| Operating Temperature Range | -40 °C to +125 °C (industrial, E grade) |
| Oscillator Mode | RC (RC = external resistor/capacitor) |
| Peripherals | POR (Power-On Reset), WDT (Watchdog Timer) |
| Pin Count | 20 |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC16C56T-RCE/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 | T0CKI — Timer0 clock input / RA4 |
| 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 |
| Pin 15 | OSC2 — Oscillator output / RC connection |
| Pin 16 | OSC1 — Oscillator input / RC connection |
| Pin 17 | NC — Not connected (per datasheet) |
| Pin 18 | NC — Not connected (per datasheet) |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C56T-RCE/SS is suitable for 6 applications: Automotive Body Electronics, Appliance Control Boards, Security Keypads and Access Control, Remote Control and RF Encoders, Industrial Sensor Interfaces, LED Lighting Controllers.
Automotive Body Electronics
The PIC16C56T-RCE/SS fits automotive body-control modules because of its industrial -40 °C to +125 °C operating range, 3.25 V to 6 V supply tolerance, and 25 mA I/O drive directly capable of switching relay coils and small solenoids. Its 4 MHz CPU and 1.5KB OTP are sufficient to handle seat-position memory, mirror-fold sequencing, and simple wiper-interval logic without an external bus. The on-chip WDT recovers the ECU from EMC-induced firmware lockups, while the EPROM code-protection bit prevents unauthorized firmware reads. Engineers place the part on a 20-SSOP footprint near the power connector with a 100 nF decoupling cap within 5 mm of VDD.
Recommended
Appliance Control Boards
Washing-machine control boards, microwave oven keypads, and dishwasher user-interface panels use the PIC16C56T-RCE/SS because the 1.5KB OTP fits the entire user-interface state machine and timer logic, while the 12 I/O pins multiplex 7-segment displays and keypad matrix. The 33 single-cycle instruction set executes every scan task in under 1 ms, leaving CPU bandwidth for debounce and fault detection. The 4 MHz RC oscillator eliminates the cost of an external crystal, reducing BOM cost by $0.20-0.40 per board. The -40 °C to +125 °C range covers under-cabinet thermal stress and oven-door-hinge steam exposure.
Recommended
Security Keypads and Access Control
The PIC16C56T-RCE/SS drives 4x4 matrix keypads in security-system arming stations and RFID access-control readers, with the on-chip WDT guaranteeing recovery from brown-out-induced firmware lockup. The 12 I/O pins support 8 keypad rows/columns plus 4 status-LED outputs, and the 25-byte RAM buffers recent PIN entries before EEPROM hand-off. The OTP code-protection bit prevents extraction of the encryption-comparison routine. The 3.25-6 V supply range lets the part share a 5 V linear regulator with the keypad backlight driver.
Recommended
Remote Control and RF Encoders
Garage-door openers, ceiling-fan remotes, and low-end wireless key fobs pair the PIC16C56T-RCE/SS with 315/433 MHz SAW-resonator transmitters because the 4 MHz CPU generates precise timing for PWM-based Manchester or OOK encoding. The 1.5KB OTP holds button-debounce state machines, transmission sequencers, and 32-bit rolling-code buffers, while 25-byte RAM stores the most recent transmission. The wide 3.25-6 V supply range accepts 3 V coin cells or 6 V battery packs, and the low-power CMOS sleep mode extends coin-cell life to 2+ years.
Recommended
Industrial Sensor Interfaces
The PIC16C56T-RCE/SS implements simple 4-20 mA loop-powered sensor transmitters for pressure, temperature, and flow sensors in factory-automation cabinets. The 12-bit-equivalent instruction width, on-chip WDT, and industrial temperature range suit the noisy, thermally-stressed plant environment. With one ADC channel bit-banged from the I/O pins, the part can digitize a thermistor or RTD bridge and serialize the result via UART to a PLC. The EPROM code protection safeguards calibration constants.
Recommended
LED Lighting Controllers
Architectural and stage-lighting fixture controllers use the PIC16C56T-RCE/SS to generate DMX-512 or 0-10V dimming signals because the 4 MHz CPU produces 250 kbaud DMX timing within 1% tolerance without an external UART crystal. The 12 I/O pins drive 4 MOSFET dimmers plus an RS-485 transceiver enable, and 1.5KB OTP stores 16 lighting scenes. The wide 3.25-6 V supply range and -40 to +125 °C rating cover outdoor fixture thermal extremes, while the WDT recovers the controller from ESD-induced firmware lockups.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C56T-RCE/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C56T-10E/SS | PIC16C56T-RCI/SS | PIC16C56T-RC/SS | PIC16C55T-RCE/SS | PIC16C57C-RCE/SS |
|---|---|---|---|---|---|---|
| Package | 20-SSOP | 20-SSOP | 20-SSOP | 20-SSOP | 20-SSOP | 20-SSOP |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 4 MHz | 10 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Program Memory (OTP) | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB | 512 B | 3 KB |
| RAM Size | 25 B | 25 B | 25 B | 25 B | 25 B | 72 B |
| I/O Pins | 12 | 12 | 12 | 12 | 12 | 20 |
| Operating Temperature | -40 to +125 °C | -40 to +125 °C | -40 to +85 °C | 0 to +70 °C | -40 to +125 °C | -40 to +125 °C |
| Oscillator Mode | RC | RC | RC | RC | RC | RC |
| Unit Price @ Qty 1 (USD, as of 2026-09-17) | 1.85 | 1.95 | 1.75 | 1.55 | 1.80 | 2.20 |
Key Differentiators
- Highest-grade industrial -40 to +125 °C option within the PIC16C56 SSOP family (vs PIC16C56T-RC/SS)
- 4 MHz RC oscillator eliminates external crystal cost (vs PIC16C56-HS/SS (crystal variant))
- Mature long-life-cycle product still shipping in 2026 (vs PIC16F84A (newer flash alternative))
Design Notes
Estimated: OTP memory cannot be erased or rewritten. A single bit error in firmware forces full MCU replacement, so always program a known-good golden unit and use Microchip's MPLAB PM3 or PICSTART Plus for the high-voltage (~13V VPP) parallel programming cycle. Allow at least 50 ms after VDD stabilization before applying VPP, otherwise the POR circuit may not release the CPU in time for programming. Engineers commonly mistake this for a 'dead' OTP part during initial bring-up.
Place a 100 nF ceramic decoupling capacitor within 5 mm of the VDD pin (pin 14) with a wide ground return directly to VSS (pin 5). Keep the OSC1/OSC2 traces short and surrounded by ground pour. For RC oscillator mode, place the resistor and capacitor adjacent to the OSC pins; for crystal mode, add a 1 MΩ parallel feedback resistor across the crystal to bias the internal inverter into its linear region. Long OSC traces pick up radiated noise that periodically resets the MCU via the WDT.
Estimated: at VDD=5V, 4 MHz clock, and all I/O pins switching, the PIC16C56T-RCE/SS draws approximately 5-7 mA. In sleep mode with WDT disabled, the part drops below 1 µA, making it suitable for battery-powered remote controls. The brown-out detector (only present on later 'L' and 'C' revision parts) is NOT included on the standard PIC16C56 die, so external brown-out protection is required for automotive 12V-transient environments. Add a 5.1 V Zener clamp on VDD if the input rail can swing above 6 V.
Compliance Information
RoHS and REACH compliant per Microchip product page; lead-free SSOP-20 package. The PIC16C56T-RCE/SS is NOT AEC-Q100 qualified; for AEC-Q100 automotive applications consider the newer PIC16F-series or a Q-graded PIC16C variant. Halogen-free per Microchip 2014 transition.
