PIC16LC56A-04I/P - 8-Bit 1.5KB OTP MCU, 4MHz, 18-PDIP | Microchip
MPN: PIC16LC56A-04I/P β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.96 | $1.96 |
| 10 | $1.78 | $17.80 |
| 100 | $1.52 | $152.00 |
| 500 | $1.34 | $670.00 |
| 1,000 | $1.18 | $1,180.00 |
PIC16LC56A-04I/P Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory, data RAM, and peripheral I/O onto one silicon die. The PIC16C5X family specifically implements a RISC architecture with 33 single-word, single-cycle instructions, providing 2:1 code compression versus competitors in its class. MCUs form the lowest level of the embedded computing hierarchy: microcontroller -> embedded processor -> SoC -> computer. The 'LC' suffix designates the low-power CMOS process variant; the 'A' suffix denotes an enhanced silicon revision with improved oscillator stability and lower current consumption.
Key differentiating features include 12 I/O pins with individually programmable direction, an 8-bit real-time timer/counter (TMR0) with 8-bit programmable prescaler, a watchdog timer for code-lock recovery, and power-saving SLEEP mode. The OTP EPROM allows factory or prototype programming in plastic packages. The 4 MHz clock enables deterministic instruction execution at 1 us per instruction cycle, simplifying real-time control loops.
Typical applications include industrial control, embedded automation, motor control (small DC/Stepper drivers), metering (utility, energy, water), low-power IoT end-node sensor reading, and legacy board redesigns. The 18-pin PDIP package remains popular for hobby, education, and through-hole assembly lines.
Designers should note that the OTP memory cannot be reprogrammed; for field updates choose the PIC16F56A flash variant. For new designs requiring C compiler support and modern peripherals, the PIC16F1xxx family offers migration paths in the same 18-pin DIP package.
This page synthesizes distributor pricing, pin-compatible alternatives, and practical design notes beyond the manufacturer datasheet summary.
Drop-in alternatives for PIC16LC56A-04I/P 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 PIC16LC56A-04I/P (same form factor and footprint) β differing in Architecture, Package, Program Memory Type, RoHS Status, Watchdog Timer.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C56A-04I/P
β Drop-Inβ In Stock
$2.3 / Unit
View Datasheet βPIC16F56A-I/P
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
PIC16C56-04I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16LC54A-04I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16CR56A-04I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16LC56A-04I/P Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit Microcontroller (MCU) |
| Architecture | PIC RISC (PIC16C5X family) |
| Program Memory | 1.5 KB OTP EPROM |
| RAM | 25 bytes |
| Maximum Clock Speed | 4 MHz |
| Instruction Set | 33 single-word, single-cycle instructions |
| I/O Pins | 12 |
| Supply Voltage (Vdd) | 3.0 V to 6.25 V |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Package | 18-pin PDIP (0.300 inch, 7.62 mm) |
| Mounting Type | Through-Hole |
| Timer/Counters | 1 x 8-bit (TMR0) with 8-bit prescaler |
| Watchdog Timer | Yes (with on-chip RC oscillator) |
| Program Memory Type | OTP EPROM (one-time programmable) |
| RoHS Status | Compliant (Pb-free) |
| MSL Level | Not applicable (through-hole package) |
PIC16LC56A-04I/P Pin Configuration
| Pin 1 | RA2 β GPIO Port A bit 2 |
| Pin 2 | RA3 β GPIO Port A bit 3 |
| Pin 3 | RA4/T0CKI β GPIO Port A bit 4 / Timer0 clock input |
| Pin 4 | MCLR β Master Clear Reset input (active low) |
| Pin 5 | VSS β Ground reference |
| Pin 6 | RB0 β GPIO Port B bit 0 |
| Pin 7 | RB1 β GPIO Port B bit 1 |
| Pin 8 | RB2 β GPIO Port B bit 2 |
| Pin 9 | RB3 β GPIO Port B bit 3 |
| Pin 10 | RB4 β GPIO Port B bit 4 |
| Pin 11 | RB5 β GPIO Port B bit 5 |
| Pin 12 | RB6 β GPIO Port B bit 6 |
| Pin 13 | RB7 β GPIO Port B bit 7 |
| Pin 14 | VDD β Positive supply voltage (3.0V to 6.25V) |
| Pin 15 | OSC2 β Oscillator output (crystal/RC) |
| Pin 16 | OSC1 β Oscillator input (crystal/RC/external clock) |
| Pin 17 | RA0 β GPIO Port A bit 0 |
| Pin 18 | RA1 β GPIO Port A bit 1 |
Typical Applications
PIC16LC56A-04I/P is suitable for 7 applications: Industrial Control and Automation, Motor Control (Small DC / Stepper), Utility Metering (Water / Gas / Energy), IoT Sensor End Nodes and Low-Power Devices, Consumer Appliance Control, Hobby, Education, and Legacy Board Redesign, Automotive Aftermarket and Subsystems.
Industrial Control and Automation
The PIC16LC56A-04I/P fits industrial control applications because of its 4 MHz deterministic instruction cycle (1 us per instruction), 12 GPIO for sensor and actuator interfacing, and -40 C to +85 C industrial temperature rating. According to PIC16C5X family documentation, the 33 single-cycle instruction RISC core enables real-time control loops with predictable timing - critical for PLC digital I/O modules, conveyor sequencing, and relay driver boards. The 3.0V-6.25V supply range supports both 24V-bus-derived 5V rails and 3.3V logic, making it a flexible slave controller.
Recommended
Motor Control (Small DC / Stepper)
Small DC and stepper motor control applications benefit from the PIC16LC56A-04I/P's 12 GPIO sufficient to drive H-bridge logic inputs, direction, enable, and fault feedback lines for one or two small motors. According to Microchip application notes, the 4 MHz clock with 1 us instruction cycle provides adequate PWM edge timing for low-RPM brushed DC motors in appliances, fans, and pumps. The watchdog timer with on-chip RC oscillator ensures code-lock recovery in noisy motor environments, while industrial temperature grade supports under-hood-adjacent deployments.
Recommended
Utility Metering (Water / Gas / Energy)
Utility metering endpoints leverage the PIC16LC56A-04I/P for low-power pulse counting, mechanical encoder reading, and tamper detection in electricity, water, and gas meters. According to PIC16C5X family datasheet, the SLEEP mode plus watchdog wake-up enables battery lifetimes of 5-10 years on a single lithium cell when the MCU sleeps between sensor pulses. The 1.5KB code space holds calibrated metering firmware, and the 25-byte RAM is sufficient for BCD counter accumulators. Industrial temperature rating tolerates outdoor meter enclosure conditions.
Recommended
IoT Sensor End Nodes and Low-Power Devices
IoT sensor end nodes and low-power battery devices leverage the PIC16LC56A-04I/P's LC CMOS process for sub-microwatt SLEEP currents, allowing multi-year battery life on simple duty-cycled sensor nodes. According to Microchip low-power MCU documentation, the watchdog timer can wake the MCU from SLEEP every few seconds to read a temperature or humidity sensor and transmit via a companion radio. The 12 GPIO supports I2C bit-banged sensor interfaces, status LEDs, and a wake-up button. Wide 3.0-6.25V supply accepts 3.6V lithium thionyl chloride cells directly.
Recommended
Consumer Appliance Control
Consumer appliance control boards - including coffee makers, microwave keypads, washing machine user interfaces, and air-conditioner remotes - use the PIC16LC56A-04I/P for keyboard scanning, LED/buzzer driving, and relay sequencing. According to the 33-instruction RISC architecture, the part's 12 GPIO easily handles 4x4 matrix keypads plus indicator LEDs, while the 1.5KB code holds state-machine firmware. The through-hole PDIP package simplifies hand-soldering and field repair on legacy appliance production lines where SMT equipment is not available.
Recommended
Hobby, Education, and Legacy Board Redesign
Hobby, education, and legacy board redesign projects benefit from the PIC16LC56A-04I/P's through-hole 18-pin PDIP package, breadboard-friendly footprint, and the well-documented PIC16C5X instruction set taught in many university embedded courses. According to PIC16C5X educational documentation, students learn RISC assembly programming on this part before graduating to PIC16F1xxx. Legacy redesigns of 1990s-era PIC16C5X-based products can use PIC16LC56A-04I/P as a form-fit-function replacement with identical 18-pin DIP footprint, requiring no PCB changes.
Recommended
Automotive Aftermarket and Subsystems
Automotive aftermarket and subsystem applications such as alarm LED flashers, garage door openers, and 12V accessory controllers leverage the PIC16LC56A-04I/P's 6.25V absolute-maximum Vdd (with external regulator) and industrial -40 C to +85 C temperature range. According to automotive electronics guidance, the part is suitable for non-safety in-cabin accessories that do not require AEC-Q100 qualification. For under-hood or safety-critical functions, select the AEC-Q100-qualified PIC16C5X automotive variants or migrate to a PIC16F1xxx Q1 part.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC56A-04I/P β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C56A-04I/P | PIC16F56A-I/P | PIC16C56-04I/P | PIC16LC54A-04I/P | PIC16CR56A-04I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-PDIP (0.300 inch) | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same |
| Program Memory | 1.5 KB OTP EPROM | 1 KB OTP EPROM | 1.5 KB Flash | 1 KB OTP EPROM | 512 B OTP EPROM | 1.5 KB Mask ROM |
| Maximum Clock Speed | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| RAM | 25 bytes | 25 bytes | 25 bytes | 25 bytes | 25 bytes | 25 bytes |
| I/O Pins | 12 | 12 | 12 | 12 | 12 | 12 |
| Supply Voltage Range | 3.0 V to 6.25 V | 3.0 V to 6.25 V | 2.0 V to 5.5 V | 3.0 V to 6.25 V | 3.0 V to 6.25 V | 3.0 V to 6.25 V |
| Memory Type | OTP EPROM (one-time) | OTP EPROM | Flash (reprogrammable) | OTP EPROM | OTP EPROM | Mask ROM |
Key Differentiators
- Lower minimum supply voltage than non-LC siblings (vs PIC16C56A-04I/P)
- Reprogrammable flash variant available in same footprint (vs PIC16F56A-I/P)
- Larger 1.5 KB code space than smaller PIC16LC54A variant (vs PIC16LC54A-04I/P)
Design Notes
The PIC16LC56A-04I/P 'LC' CMOS process supports 3.0 V to 6.25 V operation, enabling direct 3.3 V or 5 V supply without level shifters. According to PIC16C5X datasheet, the part draws approximately 1-2 mA active at 4 MHz and under 1 uA in SLEEP mode. Add a 100 nF decoupling capacitor directly between VDD (pin 14) and VSS (pin 5), placed within 5 mm of the package leads, to suppress switching noise from internal clock trees.
Do not attempt to erase or reprogram OTP EPROM - it is one-time programmable only. According to Microchip programming documentation, attempting UV erase on the windowed CERDIP variant does NOT apply to the PDIP package; the OTP bits are physically blown during programming. For prototype iteration, use the PIC16F56A-I/P flash variant in the same 18-PDIP footprint instead. Also note that PIC16C5X has no hardware stack - nested subroutines deeper than 2 levels will silently corrupt the program counter.
Place the 4 MHz crystal or ceramic resonator (with load capacitors per resonator datasheet, typically 15-33 pF) within 10 mm of OSC1 (pin 16) and OSC2 (pin 15). According to PIC16C5X oscillator guidance, keep oscillator traces short and shield them with a ground pour to prevent digital switching noise from coupling into the clock. For cost-sensitive designs, the internal RC oscillator mode eliminates the crystal entirely but adds +/- 1% frequency tolerance over temperature.
Compliance Information
RoHS compliant Pb-free PDIP per Microchip product environmental compliance. Not AEC-Q100 qualified - not suitable for automotive safety-critical applications. Halogen-free status not explicitly stated in the verified web data.
