PIC16LC56A-04/SS - 1.5KB OTP MCU, 4MHz, 12 I/O SSOP20 | Microchip
MPN: PIC16LC56A-04/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.9 | $0.90 |
| 10 | $0.85 | $8.50 |
| 100 | $0.78 | $78.00 |
| 500 | $0.69 | $345.00 |
| 1,000 | $0.6 | $600.00 |
PIC16LC56A-04/SS Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, memory, and peripherals on a single die. The PIC16C5X family uses a RISC architecture with only 33 single-word/12-bit-wide instructions, achieving roughly 2:1 code compression over competing 8-bit MCUs in its class. Compared with broader families, this PIC sits at the entry level of the PIC16 baseline hierarchy (PIC16C5X -> PIC16 baseline -> PICmicro -> 8-bit MCU -> microcontroller -> semiconductor).
Key features include a programmable code-protection bit, a Watchdog Timer with its own on-chip RC oscillator for reliable reset, Power-on Reset, and a 4 MHz internal/external clock option with a 1:1, 1:2, 1:4, or 1:8 prescaler. The 8-bit real-time clock/counter architecture, plus 12 CMOS-compatible I/O lines, supports simple digital I/O and timer-based control tasks without external glue logic.
The device is fabricated in a low-power CMOS process optimized for the LC (low-voltage) supply range, giving the 04 speed-grade designation its 4 MHz ceiling. The SSOP-20 footprint reduces board area versus the original CERDIP-18 windowed package while preserving pin compatibility at the silicon level for the same PIC16C5X base family.
Typical applications include appliance control, sensor signal conditioning, simple motor/relay drivers, automotive body controllers (where PIC16C56A variants are AEC-Q100 supported), and battery-powered remote controls. It also fits hobbyist and educational platforms where a low pin-count baseline PIC is preferred.
When designing with this device, note that OTP memory cannot be erased in-circuit - code-protect is one-way. Place a 0.1 uF decoupling capacitor close to VDD and route the reset line away from switching nodes to avoid spurious resets from the Watchdog Timer.
This page synthesizes distributor pricing, drop-in SSOP-20 alternatives, and practical design notes not found in the bare manufacturer datasheet, giving procurement and engineering teams a single source of truth for the PIC16LC56A-04/SS.
Drop-in alternatives for PIC16LC56A-04/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 PIC16LC56A-04/SS (same form factor and footprint) — differing in Program Memory Size, Watchdog Timer, RAM Size, Core Architecture, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C56A-04/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC56AT-04/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC56A-04I/SS
✅ Drop-In✓ In Stock
$1.45 / Unit
View Datasheet →PIC16LC56AT-04I/SS
✅ Drop-In✓ In Stock
$2.05 / Unit
View Datasheet →PIC16LC56A-04/SO
✅ Drop-In✓ In Stock
$0.78 / Unit
View Datasheet →PIC16LC54A-04/SS
✅ Drop-In✓ In Stock
$3.85 / Unit
View Datasheet →PIC16LC56A-04/SS Maximum Ratings & Electrical Characteristics
| Program Memory Size | 1.5 KB (OTP) |
| RAM Size | 25 bytes |
| Data EEPROM | None |
| CPU Architecture | 8-bit RISC (PIC16C5X core) |
| Instruction Set | 33 single-word, 12-bit-wide instructions |
| Maximum Clock Frequency | 4 MHz |
| Supply Voltage (VDD) | 3.0 V to 6.25 V |
| I/O Pins | 12 |
| Timers | 1 x 8-bit timer/counter |
| Watchdog Timer | Yes (with dedicated on-chip RC oscillator) |
| Power-on Reset | Yes |
| Code Protection | Programmable via EPROM bit |
| Package | SSOP-20 |
| Mounting Type | Surface Mount |
| Operating Temperature | 0C to +70C (commercial) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
| Speed Grade | 04 (4 MHz) |
PIC16LC56A-04/SS Pin Configuration
| Pin 1 | RA0 — Port A bit 0 (digital I/O) |
| Pin 2 | RA1 — Port A bit 1 (digital I/O) |
| Pin 3 | RA2 — Port A bit 2 (digital I/O) |
| Pin 4 | RA3 — Port A bit 3 (digital I/O) |
| Pin 5 | RB0 — Port B bit 0 (digital I/O) |
| Pin 6 | RB1 — Port B bit 1 (digital I/O) |
| Pin 7 | RB2 — Port B bit 2 (digital I/O) |
| Pin 8 | RB3 — Port B bit 3 (digital I/O) |
| Pin 9 | RB4 — Port B bit 4 (digital I/O) |
| Pin 10 | RB5 — Port B bit 5 (digital I/O) |
| Pin 11 | RB6 — Port B bit 6 (digital I/O) |
| Pin 12 | RB7 — Port B bit 7 (digital I/O) |
| Pin 13 | VSS — Ground reference |
| Pin 14 | OSC1 — Oscillator input or external clock |
| Pin 15 | OSC2 — Oscillator output (crystal mode) |
| Pin 16 | RC0 — Port C bit 0 (digital I/O) |
| Pin 17 | RC1 — Port C bit 1 (digital I/O) |
| Pin 18 | RC2 — Port C bit 2 (digital I/O) |
| Pin 19 | RC3 — Port C bit 3 (digital I/O) |
| Pin 20 | VDD — Positive supply (3.0-6.25 V) |
Typical Applications
PIC16LC56A-04/SS is suitable for 7 applications: Appliance Control, Sensor Signal Conditioning, Simple Motor and Relay Drivers, Battery-Powered Remote Controls, Automotive Body Controllers (Industrial Variant), Educational and Hobbyist Platforms, LED Display and Indicator Controllers.
Appliance Control
The PIC16LC56A-04/SS is well suited to white-goods appliance controllers such as coffee makers, microwave ovens, and dishwasher user-interface boards. Its 1.5 KB OTP program memory holds typical UI state machines, sensor-scanning routines, and relay-timing logic, while the 12 GPIO pins directly drive LEDs, keypads, triac-gate optos, and buzzer transducers without external logic. The integrated Watchdog Timer with its dedicated on-chip RC oscillator prevents firmware lockups in high-EMI motor environments. Operating from 3.0 V to 6.25 V lets designers reuse the same part across 3.3 V and 5 V subsystems.
Recommended
Sensor Signal Conditioning
For low-speed sensor front-ends (thermistors, photodiodes, humidity sensors), the PIC16LC56A-04/SS provides a low-cost 8-bit ADC-free MCU paired with an external sigma-delta or ratiometric sensor. The 4 MHz instruction clock is adequate for 10-100 Hz filtered sampling, and the 12 GPIO lines multiplex multiple sensor channels plus a UART/I2C-style bit-banged link to a host controller. Its 3.0-6.25 V supply lets it share rails directly with analog sensor bridges. Watchdog and Power-on Reset ensure reliable startup in remote sensor pods.
Recommended
Simple Motor and Relay Drivers
The PIC16LC56A-04/SS's 25 mA source/sink GPIO directly sinks small 5 V relay coils and triac gates in HVAC damper controls and solenoid valve drivers. Its single 8-bit timer/counter generates accurate PWM at modest switching frequencies suitable for brushed-DC motor speed control below 1 kHz. The 1.5 KB OTP memory holds commutation tables and debounce routines for limit-switch feedback. Industrial temperature variants (-40C to +85C) tolerate underhood and outdoor enclosures where thermal stress is severe.
Recommended
Battery-Powered Remote Controls
For handheld IR/RF remote controls, the PIC16LC56A-04/SS draws microamp-level sleep current (when the application uses WDT-driven wake) and operates down to 3.0 V, allowing two AA cells in series to power the entire controller without boost conversion. The 12 GPIO pins support a 4x4 keypad matrix, IR LED drive, status LED, and a learning-mode EEPROM bit-bang interface. Its small SSOP-20 footprint fits inside slim remote housings. OTP memory reduces per-unit cost in high-volume SKUs.
Recommended
Automotive Body Controllers (Industrial Variant)
While the commercial PIC16LC56A-04/SS itself is 0C to +70C, the same die in industrial PIC16C56A-04I/SS package handles non-safety body-electronics like seat-position memory, mirror-fold, and ambient lighting where AEC-Q100 is not mandatory. The 12 GPIO pins multiplex multiple motor drivers and LED strings, and the 1.5 KB OTP holds simple sequencing state machines. The integrated Watchdog Timer adds resilience against load-dump transients. Designers targeting AEC-Q100 strict compliance should migrate to PIC16F15344 family.
Recommended
Educational and Hobbyist Platforms
The PIC16LC56A-04/SS is a popular teaching vehicle for 8-bit MCU fundamentals: RISC pipeline, OTP programming, Watchdog, and the 12-bit instruction set. Its SSOP-20 footprint fits standard 0.1 inch breakout boards and breadboard adapters, and its low cost makes it forgiving for student labs. Modern hobbyists use the LC56A as a baseline to learn before migrating to PIC16F88 or PIC16F1827 for production prototypes. The PIC16C5X datasheet (DS30453D) remains one of the clearest introductions to the PIC architecture.
Recommended
LED Display and Indicator Controllers
The PIC16LC56A-04/SS can multiplex 7-segment LED displays, 14-segment alphanumeric indicators, and dot-matrix panels using its 12 GPIO and 8-bit timer. The 4 MHz instruction rate delivers smooth 100+ Hz refresh rates for 8-digit displays without visible flicker. Its 3.0-6.25 V supply drives LED segments directly through current-limiting resistors, eliminating driver ICs in cost-sensitive designs. The Watchdog Timer prevents display freeze in vending-machine and price-tag applications.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC56A-04/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C56A-04/SS | PIC16LC56AT-04/SS | PIC16LC56A-04I/SS | PIC16LC56A-04/SO | PIC16LC54A-04/SS |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SSOP-20 | SSOP-20 - same | SSOP-20 - same | SSOP-20 - same | SOIC-20 - wider body | SSOP-20 - same |
| Program Memory | 1.5 KB OTP | 1.5 KB OTP | 1.5 KB OTP | 1.5 KB OTP | 1.5 KB OTP | 512 B OTP |
| RAM | 25 bytes | 25 bytes | 25 bytes | 25 bytes | 25 bytes | 25 bytes |
| I/O Pins | 12 | 12 | 12 | 12 | 12 | 12 |
| Max Clock | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Supply Voltage | 3.0-6.25 V | 3.0-6.25 V | 3.0-6.25 V | 3.0-6.25 V | 3.0-6.25 V | 3.0-6.25 V |
| Operating Temperature | 0C to +70C | 0C to +70C | 0C to +70C | -40C to +85C | 0C to +70C | 0C to +70C |
| Approx Unit Price (qty 100) | $0.78 | $0.78-0.85 | $0.78-0.85 | $0.85-1.00 | $0.78-0.85 | $0.65-0.75 |
Key Differentiators
- Lowest-cost Microchip drop-in within the PIC16C5X LC family (vs PIC16C56A-04/SS)
- Twice the program memory of the LC54A (vs PIC16LC54A-04/SS)
- Commercial temperature variant with same die as industrial part (vs PIC16LC56A-04I/SS)
- Compact SSOP-20 footprint over wider SOIC (vs PIC16LC56A-04/SO)
Design Notes
Place a 0.1 uF ceramic decoupling capacitor within 5 mm of the VDD pin (pin 20) on the PIC16LC56A-04/SS. Add a bulk 10 uF tantalum or aluminum polymer capacitor on the same rail if the design includes switching peripherals. The LC variant's 3.0-6.25 V range allows direct 3.3 V or 5 V supply without a regulator. Estimated: average active current at 4 MHz and 5 V is roughly 2 mA; standby current with WDT disabled drops below 1 uA.
OTP program memory cannot be erased - code-protect is one-way. Once the EPROM code-protection bit is programmed, the device cannot be re-used for new firmware, only for verified-production units. The Watchdog Timer posts configuration bits that should be cleared for non-WDT applications to avoid unintended resets. Ensure the MCLR/VPP pin (when configured as reset) is not left floating - a 10 kohm pull-up to VDD prevents spurious resets from noise.
Route the OSC1/OSC2 traces short and symmetric to minimize parasitic capacitance - aim for trace length under 10 mm and guard the crystal with a ground pour. Keep the SSOP-20 thermal pad (if present on the PCB land pattern) connected to a small ground island rather than a large copper pour; this baseline PIC does not dissipate significant power. Place the ICSP programming header access points on test pads accessible without removing the MCU from the board for production-line programming.
The PIC16LC56A-04/SS's 12 GPIO pins each source/sink 25 mA but have limited ESD protection. Add external TVS diodes on connector-driven GPIO lines exposed to user contact. For I2C-style bit-bang implementations, use 4.7 kohm pull-ups to VDD and limit bus capacitance to under 200 pF. The 4 MHz instruction rate limits reliable software-I2C to 100 kHz standard mode; faster rates require a hardware peripheral (not present on this baseline MCU).
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified; the PIC16C56A-04I/SS industrial variant is suitable for non-safety automotive body electronics, but AEC-Q100 strict applications require PIC16F family migration.
