PIC16C554-04/SO - 4MHz 8-Bit OTP MCU | Microchip | SOIC-18
MPN: PIC16C554-04/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.76 | $2.76 |
| 10 | $2.45 | $24.50 |
| 100 | $2.1 | $210.00 |
| 500 | $1.85 | $925.00 |
| 1,000 | $1.62 | $1,620.00 |
PIC16C554-04/SO Overview
An 8-bit microcontroller is a single-chip computer that integrates a CPU, RAM, program memory, and I/O peripherals on one die. Microcontrollers belong to the broader category of microprocessors and processors; the 8-bit class targets low-cost, deterministic, low-power embedded control tasks such as appliance controls, sensor interfaces, and simple user I/O. The PIC16C5x architecture is part of Microchip's PIC RISC family, optimized for compact code (only 35 instructions) and fast interrupt response.
Key features of the PIC16C554-04/SO include 200 ns instruction cycle at 4 MHz, 4 MHz maximum operating frequency, 13 bidirectional I/O pins, on-chip Power-On Reset (POR), Watchdog Timer (WDT), and an external oscillator interface. The OTP program memory supports one-time field programming, while the 80 x 8 RAM provides scratchpad data storage. Operating voltage spans 3.0 V to 5.5 V with a commercial temperature grade of 0 C to +70 C.
The device uses a Harvard RISC architecture with separate program and data buses, 8-level hardware stack, and 12-bit special-function register file. CMOS static design allows clock frequencies from DC to 4 MHz, and the SOIC-18 (7.50 mm) package is suited for cost-sensitive, surface-mount designs. The 04 speed suffix denotes the 4 MHz grade; -10 and -20 suffixes denote 10 MHz and 20 MHz grades respectively within the same PIC16C554 die.
Typical applications include automotive body electronics, industrial control logic, appliance controllers, security system keypads, and general-purpose 8-bit embedded replacement of discrete logic. The wide operating voltage and small package make it a common choice for legacy designs requiring a long-life, pin-stable controller.
Design consideration: pair the MCU with a stable external resonator or crystal on OSC1/OSC2, route MCLR with a proper RC reset network, and respect the OTP one-time-program constraint by verifying code in a windowed or flash-equivalent prototype (e.g., PIC16F554) before committing to production.
This page synthesizes distributor pricing, drop-in same-family alternatives (PIC16C554-04E/SO, PIC16C554-04I/SO, PIC16C554-20I/SO), and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16C554-04/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 PIC16C554-04/SO (same form factor and footprint) — differing in Package, Mounting Type, Program Memory Size, Program Memory Type, RAM Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C554-04E/SO
✅ Drop-In✓ In Stock
$2.1 / Unit
View Datasheet →PIC16C554-04I/SO
✅ Drop-In✓ In Stock
$1.68 / Unit
View Datasheet →PIC16C554-20I/SO
✅ Drop-In✓ In Stock
$1.55 / Unit
View Datasheet →PIC16C554T-04I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C554-04/P
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →PIC16C554-04/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Core Size | 8-bit |
| Instruction Set | 35 instructions (12-bit opcode) |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle Time | 200 ns at 4 MHz |
| Program Memory Type | OTP (One-Time Programmable) EPROM |
| Program Memory Size | 896 B (512 x 14) |
| RAM Size | 80 x 8 bytes |
| EEPROM Size | None |
| Number of I/O Pins | 13 |
| Peripherals | POR (Power-On Reset), WDT (Watchdog Timer) |
| Connectivity | None (no UART, SPI, I2C on this device) |
| Data Converters | None |
| Supply Voltage Range | 3.0 V to 5.5 V |
| Operating Temperature Range | 0 C to +70 C (commercial) |
| Oscillator Type | External (RC or crystal/resonator) |
| Package / Case | 18-SOIC (7.50 mm width, 0.295 in) |
| Supplier Device Package | 18-SOIC |
| Mounting Type | Surface Mount (Gull Wing) |
| RoHS Status | Compliant (per distributor listings) |
PIC16C554-04/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/T0CKI — Bidirectional I/O port A bit 4 / Timer0 clock input |
| Pin 4 | MCLR — Master Clear (reset) input, active low |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — Bidirectional I/O port B bit 0 / External interrupt |
| 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 5.5 V) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / clock output (crystal mode) |
| Pin 16 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 17 | RA0 — Bidirectional I/O port A bit 0 |
| Pin 18 | RA1 — Bidirectional I/O port A bit 1 |
Typical Applications
PIC16C554-04/SO is suitable for 7 applications: Appliance Control Boards, Automotive Body Electronics, Industrial Sensor Interface, Security Keypad and Access Control, Remote Control and IR Transmitter, Smart Metering and Utility Endpoints, Toys and Consumer Electronics.
Appliance Control Boards
The PIC16C554-04/SO fits appliance control boards (washing machines, microwave ovens, dishwashers) because its 8-bit RISC core, 35-instruction set, and 4 MHz deterministic 200 ns cycle execute simple state-machine code efficiently. With 896 B OTP and 80 B RAM, it can handle motor-control timing sequences, button-debounce logic, and LED-indicator multiplexing on the 13 I/O pins. The 3-5.5 V VDD range tolerates noisy rectified mains supplies common in white goods. Versus a discrete 74HC logic implementation, the MCU consolidates 5-10 logic ICs into one $2.76 part (as of 2026-09-16), reducing PCB area by 60%. The 18-SOIC footprint suits reflow-compatible assembly lines typical of consumer-appliance manufacturing. Recommended companions include the PIC16F554T-I/SO (flash prototype) and ULN2003A (relay driver).
Recommended
Automotive Body Electronics
The PIC16C554-04/SO can be used in non-safety automotive body modules (window lifters, seat controllers, mirror adjusters) where the extended-temperature PIC16C554-04E/SO variant provides -40 C to +125 C operation per Microchip datasheet 30213F. The 13 I/O drive relay coils, sense switch positions, and PWM motor-speed signals. The OTP memory stores fixed body-control firmware (one-time-programmed at the line) for cost-optimized high-volume production. AEC-Q100 qualification is NOT available for this OTP family; mission-critical ECUs must use Q-qualified PIC16F or dsPIC parts. The 18-SOIC package handles the -40 C to +125 C thermal-cycling environment typical of cabin-mounted modules. Recommended companions include the PIC16C554-04E/SO (extended temp) and LM2903 (window comparator).
Recommended
Industrial Sensor Interface
The PIC16C554-04/SO serves as a low-cost sensor-interface MCU in industrial 4-20 mA loop transmitters, photoelectric sensors, and proximity switches per Microchip datasheet 30213F. The 8-bit core, 35-instruction set, and 200 ns cycle handle pulse counting, threshold decisions, and 1-Wire or bit-banged protocol emulation on the 13 GPIO pins. With 3.0-5.5 V VDD, it can run directly from 5 V sensor rails without an LDO. The OTP memory and 80 B RAM suit fixed-function firmware that does not require field updates. The 18-SOIC surface-mount package enables compact IP67 sensor housings. The commercial 0-70 C grade is acceptable for sealed enclosures; for outdoor installs use PIC16C554-04I/SO. Recommended companions include the PIC16C554-04I/SO (industrial temp) and MAX31865 (RTD digitizer).
Recommended
Security Keypad and Access Control
The PIC16C554-04/SO is well-matched to security keypads and access-control panels where 8-bit deterministic scan-loop execution is sufficient per Microchip datasheet 30213F. Its 13 I/O drive a 4x4 matrix keypad (12 pins) plus a buzzer/LED output, while the 80 B RAM holds temporary PIN entries. With 35 instructions, scan-loop firmware fits well within the 896 B OTP budget; the WDT protects against code-lockup in unattended panels. The 18-SOIC surface-mount footprint enables slim wall-mount keypad designs. 3.0-5.5 V operation lets it share a 5 V rail with the buzzer driver and relay outputs. OTP programming prevents field firmware theft, an advantage for access-control security. Recommended companions include the PIC16F554T-I/SO (flash prototype) and 24C02 (I2C EEPROM for credential storage via bit-bang).
Recommended
Remote Control and IR Transmitter
The PIC16C554-04/SO fits low-cost IR remote controls and RF transmitters where small code size (under 512 instructions), low standby current, and simple GPIO are sufficient per Microchip datasheet 30213F. The 200 ns instruction cycle can bit-bang common IR protocols (NEC, RC5, Sony SIRC) on any GPIO with carrier frequencies up to 38 kHz. With only 13 I/O, it can drive a 5x5 keyboard matrix, an IR LED, and 3 indicator LEDs; OTP memory holds the fixed key-to-code lookup table. The 3-5.5 V VDD range supports single-cell 3 V lithium or two-AA alkaline configurations. The commercial 0-70 C grade is well within consumer-electronics operating ranges. Recommended companions include the PIC16C554-04E/SO (extended temp for outdoor) and TSAL6100 (IR emitter).
Recommended
Smart Metering and Utility Endpoints
The PIC16C554-04/SO serves as the MCU in simple electricity/water/gas meter endpoints that count pulses and display accumulated usage on an LCD or LED per Microchip datasheet 30213F. The 8-bit RISC core counts meter pulses via the RB0/INT pin and multiplexes a 7-segment display on the remaining 12 GPIO. With 80 B RAM and 896 B OTP, the firmware easily handles pulse accumulation, tariff logic, and LCD refresh. The WDT prevents lockup in unattended battery-powered meters; deep-sleep modes (microamp-range) extend battery life to 10+ years. The 3-5.5 V VDD range supports lithium-thionyl-chloride primary cells. Recommended companions include the PIC16F554T-I/SO (flash prototype) and a 32.768 kHz crystal for RTC timekeeping.
Recommended
Toys and Consumer Electronics
The PIC16C554-04/SO is a cost-optimized MCU for toys, electronic learning kits, and budget consumer devices where per-unit cost matters more than peripheral count per Microchip datasheet 30213F. The 35-instruction RISC core is simple enough to teach beginners, while the 13 I/O drive LEDs, sound chips, motor drivers, and button inputs. At $2.76 unit price as of 2026-09-16, it enables <$10 retail toy products. OTP programming prevents reverse-engineering of proprietary toy firmware. The 18-SOIC package is small enough for handheld form factors. Commercial 0-70 C temperature grade suits indoor toys. Recommended companions include the PIC16F554T-I/SO (development) and a PAM8403 (audio amplifier) for sound toys.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C554-04/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C554-04E/SO | PIC16C554-04I/SO | PIC16C554-20I/SO | PIC16C554T-04I/SO | PIC16C554-04/P |
|---|---|---|---|---|---|---|
| Package | 18-SOIC | 18-SOIC | 18-SOIC | 18-SOIC | 18-SOIC | 18-PDIP |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Maximum Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 20 MHz | 4 MHz | 4 MHz |
| Operating Temperature Range | 0 C to +70 C (commercial) | -40 C to +125 C (extended) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | 0 C to +70 C (commercial) |
| Program Memory Size | 896 B OTP | 896 B OTP | 896 B OTP | 896 B OTP | 896 B OTP | 896 B OTP |
| RAM Size | 80 B | 80 B | 80 B | 80 B | 80 B | 80 B |
| Number of I/O Pins | 13 | 13 | 13 | 13 | 13 | 13 |
| Supply Voltage Range | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V |
| Mounting Type | Surface Mount (SOIC) | Surface Mount (SOIC) | Surface Mount (SOIC) | Surface Mount (SOIC) | Surface Mount (SOIC, T&R) | Through-Hole (PDIP) |
Key Differentiators
- Commercial temperature grade at lowest cost (vs PIC16C554-04I/SO)
- Standard 4 MHz speed grade for low-power designs (vs PIC16C554-20I/SO)
- Surface-mount SOIC package for high-volume reflow (vs PIC16C554-04/P (PDIP))
- Tube packaging for low-volume / prototype runs (vs PIC16C554T-04I/SO (Tape & Reel))
Design Notes
Estimated: at VDD=5 V, 4 MHz clock, all 13 I/O as outputs sourcing 10 mA each, the PIC16C554-04/SO draws approximately 25-35 mA active current per Microchip datasheet 30213F DC characteristics. Add a 100 nF ceramic bypass capacitor within 5 mm of the VDD pin (pin 14), plus a 10 uF bulk capacitor on the VDD rail. Brown-out detection is NOT internal; design an external voltage supervisor (e.g., MCP100) or RC-reset network on MCLR if the supply can dip below 3.0 V. For battery applications, leverage the WDT and SLEEP instruction for sub-100 uA standby.
Route OSC1 (pin 16) and OSC2 (pin 15) traces as short, symmetric pairs to minimize stray capacitance, and place the crystal/resonator within 10 mm of the IC. Use a ground guard ring around the oscillator traces to reduce crosstalk with adjacent signal lines. For the MCLR pin (pin 4), place the reset resistor (typically 10 kohm) close to the pin and route the trace away from switching signals. The 18-SOIC package has a thermal pad leadframe; standard SOIC footprint pads are recommended per Microchip package drawings. Add test points on OSC1/OSC2 and MCLR for in-circuit debugging.
OTP memory cannot be erased or rewritten - verify all firmware in a PIC16F554 flash prototype before committing to OTP production programming. Estimate: an erased but unprogrammed OTP die draws 1-2 mA higher Iq than a programmed one; verify with a bench meter before final programming. Do not exceed 5.5 V on any pin including MCLR; the absolute-maximum VDD is 6.5 V per datasheet 30213F. The 35-instruction PIC16C5x core is NOT source-compatible with PIC16F1xxx enhanced cores; porting code requires re-assembly. I/O pins default to input mode on power-up; configure TRIS registers before driving outputs.
Compliance Information
RoHS compliant per distributor listings on DigiKey and Mouser. NOT AEC-Q100 qualified; OTP PIC16C5x family is not recommended for automotive safety-critical ECUs - use Q-qualified PIC16F or dsPIC parts instead. Lead-free (Pb-free) matte-tin plating per Microchip packaging specifications.
