PIC16LC554-04/SO - 8-Bit 4MHz OTP MCU, 896B | 18-SOIC | Microchip
MPN: PIC16LC554-04/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $3.08 | $30.80 |
| 100 | $2.71 | $271.00 |
| 500 | $2.35 | $1,175.00 |
| 1,000 | $2.04 | $2,040.00 |
PIC16LC554-04/SO Overview
An 8-bit microcontroller (MCU) is a single-chip computer integrating a CPU, program memory, data RAM, and peripheral I/O on a single silicon die. It belongs to the broader category of microcontrollers -> embedded processors -> semiconductors. The PIC16C5X family, of which the PIC16LC554 is a member, is built on a Harvard architecture with separate program and data buses, allowing instruction fetch and data access to occur in a single instruction cycle (200 ns at 20 MHz, or 1 microsecond at 4 MHz on this part). Only 35 single-word instructions need to be learned, making it one of the simplest MCU families to program in assembly.
Key features include 13 programmable digital I/O lines across two ports, a watchdog timer with on-chip RC oscillator for reliable recovery from code faults, a power-on reset (POR) circuit, and an operating voltage range of 3.0 V to 6.25 V from a single supply rail. The "LC" suffix indicates low-power CMOS operation with extended commercial temperature-grade capability, while the "-04" speed grade denotes a 4 MHz oscillator input maximum on this low-voltage part. The 18-SOIC (SO) gull-wing surface-mount package measures approximately 11.7 mm x 7.5 mm with a 1.27 mm pitch.
Architecture is a classic 12-bit instruction-word PIC16C5X core with a two-stage pipeline, 8-level hardware stack, and direct/indirect data addressing. With 80 bytes of general-purpose RAM and a 14-bit-wide program word, the part targets simple control loops, sensor interfacing, and human-machine interface (HMI) front panels rather than compute-heavy workloads. In-system emulation is not supported on this OTP variant; development is performed on the windowed CERDIP PIC16C554 JW package.
Typical applications include consumer appliance control, simple sensor signal conditioning, replacement of discrete logic in cost-sensitive embedded products, white-goods user-interface boards, low-end remote-control transmitters, and battery-powered instrument panels. The wide 3.0 V to 6.25 V supply tolerance allows direct operation from regulated 5 V rails or two alkaline cells via a low-dropout regulator.
When designing with this device, plan for OTP programming: code is committed via a programming fixture and is non-erasable. Allocate sufficient margin in the 896-byte program memory for stack-driven ISRs and library overhead, and use the watchdog timer in any field-deployed product to recover from EMI-induced code mis-execution.
This page synthesizes distributor pricing, OTP-only constraint guidance, and pin-compatible drop-in alternatives not found in the manufacturer datasheet summary.
Drop-in alternatives for PIC16LC554-04/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 PIC16LC554-04/SO (same form factor and footprint) — differing in Program Memory Size, Program Memory Type, Core Architecture, Mounting Type, Number of I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C554-04/SO
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC16LC554-04/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC554-04E/SO
✅ Drop-In✓ In Stock
$1.71 / Unit
View Datasheet →PIC16LC554-04I/SO
✅ Drop-In✓ In Stock
$2.12 / Unit
View Datasheet →PIC16LC554-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC554-04/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 16C, 8-bit RISC, Harvard |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 896 B (512 x 14-bit) |
| Data RAM | 80 B |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle Time | 1 microsecond at 4 MHz |
| Supply Voltage Range | 3.0 V to 6.25 V |
| Number of I/O Pins | 13 |
| Number of Pins | 18 |
| Package Type | 18-SOIC (SO), 0.300 inch body width, gull-wing |
| Terminal Form | GULL WING |
| Package Code | SOP (SOIC-18) |
| Temperature Grade | COMMERCIAL |
| Operating Temperature | 0C to +70C (commercial grade) |
| Number of Instructions | 35 |
| Stack Depth | 2-level hardware stack (PIC16C5X core) |
| Watchdog Timer | Yes, with on-chip RC oscillator |
| Power-On Reset | Yes |
| Mounting Type | Surface Mount |
PIC16LC554-04/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 | RA4 — Bidirectional I/O port A bit 4 (open-drain on some PIC16C5X variants) |
| Pin 4 | MCLR — Master clear reset input (active-low), tie to VDD via resistor |
| 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, 3.0 V to 6.25 V |
| Pin 15 | OSC2 — Oscillator output, connect to crystal or resonator |
| Pin 16 | OSC1 — Oscillator input, connect to crystal or resonator |
| Pin 17 | RA0 — Bidirectional I/O port A bit 0 |
| Pin 18 | RA1 — Bidirectional I/O port A bit 1 |
Typical Applications
PIC16LC554-04/SO is suitable for 6 applications: Consumer Appliance Control, Battery-Powered Sensor Node, Remote Control Transmitter, Industrial Indicator Panel, Simple Logic Replacement (Glue Logic), Cost-Sensitive HMI Front Panel.
Consumer Appliance Control
The PIC16LC554-04/SO fits white-goods user-interface boards (washing machines, microwave ovens, dishwashers) because its 13 I/O lines are sufficient to drive 7-segment LED displays, keypads, and a relay matrix without external logic. The 896-byte OTP program memory holds state-machine firmware with comfortable margin, while the 3.0 V to 6.25 V supply tolerance allows direct operation from a rectified 5 V rail. Unlike flash MCUs, the OTP die eliminates in-field reprogramming risk and keeps per-unit cost low in high-volume SKUs where firmware is locked at production.
Recommended
Battery-Powered Sensor Node
The PIC16LC554-04/SO suits low-duty-cycle battery-powered sensor transmitters because its PIC16C5X core consumes only a few hundred microamps at 4 MHz and 3.3 V. The 80-byte RAM is adequate to buffer a sensor reading and a few state variables; the 13 I/O pins can drive a UART to a radio module, sample a thermistor, and read a push-button wake-up source. The 3.0 V minimum supply allows direct operation from two AA alkaline cells down to about 2.0 V with a boost converter. Compared with modern ARM Cortex-M0+ MCUs, the PIC16LC554 trades debug features for ultra-low BOM cost in disposable applications.
Recommended
Remote Control Transmitter
The PIC16LC554-04/SO is well-matched to IR/RF remote control transmitters because its 4 MHz oscillator and 1 microsecond instruction cycle provide precise timing for 38 kHz carrier generation without hardware PWM. The 13 digital I/O lines support a 4-by-4 keypad matrix, an LED indicator, and a transmit enable pin. With OTP program memory holding key-code lookup tables and a rolling-code algorithm in 896 bytes, this part ships in millions of TV/STB universal remote SKUs. The commercial temperature grade (0C to +70C) covers indoor use; choose the I-suffix variant for outdoor or automotive cabin remotes.
Recommended
Industrial Indicator Panel
The PIC16LC554-04/SO drives standalone industrial status indicator panels with multiplexed LED displays and discrete output relays. The 13 I/O pins are split between segment lines (8) and digit-select lines (up to 4) plus two relay controls; the on-chip watchdog timer and power-on reset handle plant-floor EMI events that would crash simpler controllers. The OTP memory is well-suited to designs where firmware is qualified once and produced for the lifetime of the equipment. For harsh 24V or 48V plant environments, add a regulator and TVS protection around the MCU.
Recommended
Simple Logic Replacement (Glue Logic)
The PIC16LC554-04/SO consolidates discrete 74HC CMOS logic gates, latches, and timing circuits into a single programmable part when the BOM cost of the discrete solution exceeds the MCU. With 13 I/O and 1 microsecond response time, it replaces dozens of gates while adding diagnostics (pulse counting, error-flag outputs) that discrete logic cannot provide. The OTP memory locks in the glue-logic configuration at programming time, preventing field tampering. Compared with discrete logic, the trade-off is the need for a programmer fixture on the production line.
Recommended
Cost-Sensitive HMI Front Panel
The PIC16LC554-04/SO powers low-end human-machine interface front panels with rotary encoder input, multi-character LCD driving via software, and PWM buzzer control. Its 13 I/O lines can drive an 8-character 14-segment LCD with an external resistor network, read a quadrature encoder, and toggle a backlight MOSFET. The 80-byte RAM suffices for menu navigation state and debounced input buffers; the OTP memory locks the menu structure at production. The 18-SOIC commercial temperature grade is adequate for indoor kiosk panels; choose the I-suffix for factory-floor deployment.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC554-04/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C554-04/SO | PIC16LC554-04/SS | PIC16LC554-04E/SO | PIC16LC554-04I/SO | PIC16LC554-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC | 18-SOIC - same | 20-SSOP - different | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same |
| Program Memory | 896 B OTP | 896 B OTP | 896 B OTP | 896 B OTP | 896 B OTP | 896 B OTP |
| RAM | 80 B | 80 B | 80 B | 80 B | 80 B | 80 B |
| Maximum Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Supply Voltage Range | 3.0 V to 6.25 V | 4.5 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 | 3.0 V to 6.25 V |
| Temperature Grade | Commercial (0C to +70C) | Commercial | Commercial | Extended (E-suffix) | Industrial (-40C to +85C) | Industrial (-40C to +85C) |
| I/O Pin Count | 13 | 13 | 13 | 13 | 13 | 13 |
Key Differentiators
- 3.0 V minimum supply voltage (vs 4.5 V on non-LC PIC16C554) (vs PIC16C554-04/SO)
- Industrial temperature grade option without pinout change (vs PIC16LC554-04I/SO)
- Same-die SSOP-20 alternative for space-constrained layouts (vs PIC16LC554-04/SS)
Design Notes
Operate the PIC16LC554-04/SO from a regulated 3.3 V or 5 V rail. Decouple VDD (pin 14) with a 100 nF ceramic capacitor placed within 5 mm of the pin, plus a 10 microfarad bulk capacitor if the supply is shared with relays. The wide 3.0 V to 6.25 V input range gives 0.75 V margin above a 3.3 V rail, which is sufficient to absorb regulator tolerance and IR drop on long PCB traces. Brown-out detection is not built in; an external voltage supervisor such as MCP100 or MCP809 is recommended for any line-powered product.
OTP microcontrollers cannot be erased or re-flashed. Plan firmware versioning and lockbits before committing code, and always program at least two engineering samples first to verify in-circuit behavior. Code-protect bits must be set after programming to prevent pattern readback. For development, use the PIC16C554 JW windowed CERDIP part or a compatible flash MCU such as PIC16F84A-I/SO as a software emulation target, then port the verified firmware to the OTP PIC16LC554-04/SO for production.
Route the oscillator traces (OSC1 pin 16, OSC2 pin 15) as short as possible and keep digital switching traces away from them to minimize clock jitter. Place MCLR (pin 4) with a 10 kohm pull-up to VDD; add a 100 nF cap to ground on MCLR only if a manual reset pushbutton is wired in. The 18-SOIC package is pin-compatible with the 18-pin DIP footprint adapter for breadboard prototyping, but pay attention to the 1.27 mm SOIC pitch versus the 2.54 mm DIP pitch when laying out the PCB.
Compliance Information
RoHS compliance status not stated in the verified web data. Microchip OTP PIC16C5X family parts were originally released before widespread RoHS adoption; verify with the manufacturer product page or specific lot documentation before placing orders for RoHS-required applications.
