PIC16C56-HSE/P - 8-bit PIC MCU, 1.5KB OTP, 16MHz, 18-PDIP | Microchip
MPN: PIC16C56-HSE/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.45 | $2.45 |
| 10 | $2.18 | $21.80 |
| 100 | $1.92 | $192.00 |
| 500 | $1.71 | $855.00 |
| 1,000 | $1.5 | $1,500.00 |
PIC16C56-HSE/P Overview
A PIC16C5x microcontroller is a member of the original Microchip PIC family of 8-bit Harvard-architecture microcontrollers. The 12-bit-wide instruction set delivers highly symmetrical 2:1 code compression versus other 8-bit microcontrollers in its class. PIC16C5x devices integrate the CPU, program memory, RAM, and peripherals onto a single CMOS die, making them drop-in controllers for cost-sensitive embedded applications that do not require in-system reprogrammability.
Key features include 12 digital I/O pins, a Watchdog Timer (WDT) for unattended operation, and a Power-On Reset (POR) circuit that holds the device in reset until VDD reaches a valid level. The device operates from a 5V supply across the commercial 0C to +70C range (HSE operating range). With a 16MHz oscillator and a 4-cycle instruction clock, each instruction executes in 250ns, providing deterministic real-time control suitable for state machines, simple sensor interfaces, and consumer appliances.
Architecturally, the PIC16C5x uses a two-stage pipeline with separate program and data buses (Harvard architecture). The 12-bit program counter addresses up to 2K instructions, and the 7-bit file-select register provides 128 bytes of register/SRAM address space (only 25 bytes general-purpose). The ALU is 8 bits wide and operates directly on any register, simplifying C and assembly coding.
Typical applications include low-cost consumer appliances, automotive body electronics (non-safety), security keypads, simple LED/LCD drivers, and replacement of discrete logic in legacy designs. Industrial users also deploy PIC16C5x for hard-coded protocol converters and appliance timer modules where OTP cost is preferred over flash reprogrammability.
When designing with this device, note that OTP memory cannot be erased or rewritten; firmware must be 100 percent verified before programming. A 10kohm pull-up on MCLR is recommended unless the internal POR is used, and decoupling caps (0.1uF plus 10-47uF bulk) must be placed close to VDD and VSS pins to suppress oscillator noise.
This page synthesizes distributor pricing, drop-in alternatives within the PIC16C5x family, and practical design notes not consolidated in any single manufacturer datasheet.
Drop-in alternatives for PIC16C56-HSE/P — 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-HSE/P (same form factor and footprint) — differing in Package, Core Architecture, Mounting Type, Maximum Clock Frequency, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C56-HSI/P
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC16C56-XT/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C56-LP/P
✅ Drop-In✓ In Stock
$3.39 / Unit
View Datasheet →PIC16C57-XT/P
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →PIC16C55-XT/P
✅ Drop-In✓ In Stock
$4.05 / Unit
View Datasheet →PIC16C56AT-04E/SO
✅ Drop-In✓ In Stock
$1.81 / Unit
View Datasheet →PIC16C56-HSE/P Maximum Ratings & Electrical Characteristics
| Core Processor | PIC |
| Core Size | 8-bit |
| Core Architecture | Harvard, RISC |
| Instruction Set Width | 12-bit |
| Program Memory Size | 1.5 KB (1K x 12) OTP |
| RAM Size | 25 x 8 bytes |
| Maximum Clock Frequency | 16 MHz |
| Number of I/O Pins | 12 |
| Supply Voltage (VDD) | 5 V (typical) |
| Oscillator Mode | External high-speed crystal/resonator (HSE) |
| Peripherals | Power-On Reset (POR), Watchdog Timer (WDT) |
| Package | 18-pin PDIP (0.300 inch, 7.62 mm) |
| Mounting Type | Through Hole |
| Operating Temperature | 0C to +70C (commercial, HSE range) |
| RoHS Status | Compliant |
| Program Memory Type | OTP (one-time programmable) |
| Series | PIC 16C |
PIC16C56-HSE/P 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 |
| 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 (5V) |
| Pin 15 | OSC2 — Oscillator output (crystal/resonator connection) |
| Pin 16 | OSC1 — Oscillator input (crystal/resonator connection) |
| Pin 17 | RA0 — Bidirectional I/O port A bit 0 |
| Pin 18 | RA1 — Bidirectional I/O port A bit 1 |
Typical Applications
PIC16C56-HSE/P is suitable for 6 applications: Consumer Appliance Control, Automotive Body Electronics, Security Keypad and Access Control, LED Display and Sign Driver, Industrial Sensor Interface Module, Toys and Hobby Electronics.
Consumer Appliance Control
The PIC16C56-HSE/P suits low-cost consumer appliances - washing-machine timers, microwave keypads, and rice-cooker controllers - because its 1.5KB OTP program memory holds compact state-machine firmware at lower per-unit cost than flash. The 12 digital I/O pins drive 7-segment displays, relay coils, and tactile keypads directly. With the 16MHz HSE oscillator, the device scans keys and updates outputs every 250ns instruction cycle, eliminating mechanical bounce artifacts. Watchdog Timer recovers from power-line brownouts and ESD-induced lockups in unattended home environments. The PIC16C5x 12-bit instruction set compresses appliance code by 2:1 versus typical 8-bit CISC controllers, fitting full product behavior into 1KB of OTP.
Recommended
Automotive Body Electronics
The PIC16C56-HSE/P powers non-safety automotive body modules - window controllers, mirror adjusters, seat-position memories - where 5V supply, 16MHz clock, and integrated Watchdog Timer meet the cost and reliability targets of body-electronics ECUs. The 12-bit OTP delivers deterministic 250ns instruction cycles for sensor debouncing and motor-PWM generation. The PIC16C5x industrial temperature variants survive under-hood thermal stress. Note: this part is commercial-temperature grade; for under-hood deployment use the automotive-qualified PIC16C56-HSE/P automotive-equivalent. Pair with a CAN or LIN transceiver for body-network integration, and a 5V automotive regulator such as the LM2931 for transient suppression.
Recommended
Security Keypad and Access Control
The PIC16C56-HSE/P is widely used in electronic door locks, alarm keypads, and RFID reader controllers because the OTP memory prevents code extraction and the 16MHz clock handles 12-key matrix scanning with sub-millisecond debounce. The 12 I/O pins directly drive a 4x3 or 4x4 matrix keypad without external multiplexer ICs, reducing BOM cost. Watchdog Timer resets the MCU if firmware locks up due to EMI from the magnetic lock coil. The Harvard architecture isolates program bus from data bus, preventing code-pinning attacks common on von-Neumann MCUs. Pair with a piezo buzzer for keypress feedback and a magnetic-reed door sensor on RB0 interrupt for tamper detection.
Recommended
LED Display and Sign Driver
The PIC16C56-HSE/P drives scrolling LED signs, scoreboards, and dot-matrix displays by multiplexing rows and columns at the 16MHz instruction rate, achieving flicker-free refresh above 100Hz with 8 columns. The 12 I/O pins can charlieplex 12 LEDs or matrix-drive 8x4 without external drivers, or sink column transistors for larger arrays. The 1.5KB OTP stores full font tables plus animation state machines. The integrated Watchdog Timer recovers from ESD-induced lockups in outdoor installations. PIC16C5x 12-bit code density allows complex bitmap patterns and scrolling algorithms within the 1K-word program space, making this part a workhorse for low-cost commercial signage.
Recommended
Industrial Sensor Interface Module
The PIC16C56-HSE/P converts legacy analog sensor signals into digital pulses for factory PLCs and SCADA systems. Although the MCU itself lacks an ADC, external sigma-delta or dual-slope converters connect to RB ports for 16-bit effective resolution. The 16MHz clock handles RS-232/RS-485 bit-banged communication at standard baud rates without a UART peripheral. Watchdog Timer recovers the module if the host PLC communication link is lost. The 18-pin PDIP through-hole package is field-replaceable on legacy equipment where surface-mount is impractical. PIC16C5x parts are common in industrial 4-20mA loop isolators and frequency-to-voltage converters still deployed in process plants.
Recommended
Toys and Hobby Electronics
The PIC16C56-HSE/P remains popular in hobby robotics, RC controllers, and educational kits because its simplicity - 33 instructions, 18-pin PDIP, breadboard-friendly - lets students and hobbyists learn embedded programming without complex toolchains. The 16MHz instruction rate is fast enough for line-following robots, servo pulse generation, and IR remote decoding. OTP memory prevents code tampering in commercial toy products while keeping unit cost low. The PIC16C5x is also commonly used as a replacement for legacy 4-bit MCU designs in vintage-electronics restoration, where its 12 I/O pins mimic the I/O count of older Motorola 6805 and Zilog Z8 controllers. MPLAB IDE and PICkit programmers support the entire PIC16C5x family.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C56-HSE/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C56-HSI/P | PIC16C56-XT/P | PIC16C56-LP/P | PIC16C57-XT/P | PIC16C55-XT/P |
|---|---|---|---|---|---|---|
| Package | 18-PDIP (0.300 in, 7.62 mm) | 18-PDIP (0.300 in, 7.62 mm) | 18-PDIP (0.300 in, 7.62 mm) | 18-PDIP (0.300 in, 7.62 mm) | 18-PDIP (0.300 in, 7.62 mm) | 18-PDIP (0.300 in, 7.62 mm) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Size | 1.5 KB (1K x 12) OTP | 1.5 KB (1K x 12) OTP | 1.5 KB (1K x 12) OTP | 1.5 KB (1K x 12) OTP | 3 KB (2K x 12) OTP | 768 B (512 x 12) OTP |
| RAM Size | 25 bytes | 25 bytes | 25 bytes | 25 bytes | 72 bytes | 25 bytes |
| Maximum Clock Frequency | 16 MHz | 16 MHz (HSI mode) | 4 MHz (XT mode) | 200 kHz (LP mode) | 4 MHz (XT mode) | 4 MHz (XT mode) |
| Number of I/O Pins | 12 | 12 | 12 | 12 | 20 | 12 |
| Instruction Set Width | 12-bit | 12-bit | 12-bit | 12-bit | 12-bit | 12-bit |
| Peripherals | POR, WDT | POR, WDT | POR, WDT | POR, WDT | POR, WDT | POR, WDT |
Key Differentiators
- Lower unit cost versus flash-based PIC16F54 in high-volume production (vs PIC16F54)
- Larger program memory within same PIC16C5x family (vs PIC16C55-XT/P)
- Faster maximum clock than XT-mode siblings (vs PIC16C56-XT/P)
Design Notes
Decouple VDD (pin 14) with a 0.1uF ceramic capacitor placed within 5mm of the package, plus a 10-47uF bulk tantalum or aluminum electrolytic on the same supply rail. PIC16C5x devices draw brief current spikes on each internal state transition; inadequate decoupling causes oscillator instability and unexpected code jumps. MCLR (pin 4) requires a 10kohm pull-up to VDD for normal operation unless the internal POR is the only reset source required. A series resistor (100-470 ohm) on MCLR protects against ESD.
PIC16C56 OTP memory cannot be erased or rewritten - a programming error destroys the part. Verify configuration bits (oscillator selection, WDT enable, code-protect) before programming, and always program a known-good firmware image as the final step. The PIC16C5x configuration word sets the oscillator mode; HSE corresponds to a 16 MHz crystal. Programming HSE firmware onto a board with a 4 MHz crystal causes oscillator failure or out-of-spec timing. Use a PICkit 3 or MPLAB PM3 for production programming.
Estimated: At 5V VDD, 16 MHz clock, and all 12 I/O pins driving CMOS loads, the PIC16C56-HSE/P draws approximately 10-15 mA active current. With a thermal resistance of approximately 100 C/W for the 18-pin PDIP package, the junction-to-ambient rise is roughly 1.0-1.5 C above ambient at room temperature - thermal management is not a concern. However, at extended industrial temperatures (-40C to +85C), verify oscillator start-up margins using Microchip application note AN588.
Compliance Information
RoHS and REACH compliance per Microchip product page. AEC-Q100 not qualified - this is a commercial-grade part. For automotive applications, contact Microchip for PIC16C56 automotive-grade equivalents.
