PIC16C554T-04/SO - 4MHz 8-bit OTP MCU 13 I/O | Microchip
MPN: PIC16C554T-04/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.67 | $1.67 |
| 10 | $1.58 | $15.80 |
| 100 | $1.42 | $142.00 |
| 500 | $1.28 | $640.00 |
| 1,000 | $1.15 | $1,150.00 |
PIC16C554T-04/SO Overview
What is an 8-bit OTP microcontroller? An 8-bit OTP (One-Time Programmable) microcontroller is a single-chip computer that executes 8-bit-wide instructions and stores its program memory in PROM cells that can be written exactly once. The PIC16C554 belongs to the broader category of microcontrollers -> 8-bit MCUs -> PIC16 family -> CMOS OTP mid-range devices. Its 35 single-word RISC instruction set simplifies code generation and reduces development time versus complex CISC architectures, while its OTP memory reduces unit cost compared to flash or EEPROM-based MCUs in volume production.
Key features include a 4MHz maximum operating frequency, 2.0V to 6.0V operating voltage range (3.3V/5V typical), 13 I/O pins with individual direction control, a watchdog timer, power-on reset, brown-out detection, and an 8-bit timer/counter. The 18-SOIC package is industry-standard and easily hand-solderable, making this part suitable for prototype and small-to-medium volume production runs.
The PIC16C554 uses Microchip's proven PIC RISC engine with a 14-bit instruction word and Harvard architecture (separate program and data buses). This two-bus design lets the CPU fetch instructions while reading/writing data in the same cycle, yielding deterministic interrupt latency and predictable timing for real-time control tasks.
Typical applications include simple appliance controllers, sensor interface front-ends, LED drivers and lighting control, automotive body electronics (in extended-temperature variants), battery chargers, and low-cost consumer products. The small footprint and minimal external component count (no crystal required when using internal RC) further reduce BOM cost.
When designing with this device, note that OTP memory cannot be reprogrammed - firmware bugs require board rework or replacement. Choose a flash-based PIC16F-series equivalent for development and field-upgradable designs, and use the PIC16C554 for cost-optimized production units where firmware is finalized.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found on the manufacturer datasheet.
Drop-in alternatives for PIC16C554T-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 PIC16C554T-04/SO (same form factor and footprint) — differing in Package, Program Memory Size, Mounting Type, Operating Temperature, Peripherals.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C554-04/SO
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC16C554T-04I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C554-04I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C554-04E/SO
✅ Drop-In✓ In Stock
$2.1 / Unit
View Datasheet →PIC16C554-04E/P
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC16C554-04/P
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →PIC16C554T-04/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Instruction Set | 35 single-word instructions, 14-bit wide |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 896 bytes (512 x 14) |
| RAM Size | 80 bytes |
| EEPROM Size | None |
| Maximum CPU Frequency | 4 MHz |
| Instruction Cycle Time | 200 ns |
| Operating Voltage Range | 2.0 V to 6.0 V |
| Typical Supply Voltage | 3.3 V / 5 V |
| I/O Pins | 13 |
| Timers | 1 x 8-bit timer/counter |
| Watchdog Timer | Yes |
| Brown-out Reset | Yes |
| Power-on Reset | Yes |
| Package | 18-SOIC (SOIC-18, 7.5 mm body width) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | 0C to +70C (commercial) |
| Lead-Free / RoHS | Refer to manufacturer datasheet |
PIC16C554T-04/SO Pin Configuration
| Pin 1 | RA2 — Port A bit 2 (bidirectional I/O) |
| Pin 2 | RA3 — Port A bit 3 (bidirectional I/O) |
| Pin 3 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Pin 4 | MCLR/VPP — Master Clear (reset) / Programming voltage input |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — Port B bit 0 / External interrupt input |
| Pin 7 | RB1 — Port B bit 1 |
| Pin 8 | RB2 — Port B bit 2 |
| Pin 9 | RB3 — Port B bit 3 |
| Pin 10 | RB4 — Port B bit 4 |
| Pin 11 | RB5 — Port B bit 5 |
| Pin 12 | RB6 — Port B bit 6 |
| Pin 13 | RB7 — Port B bit 7 |
| Pin 14 | VDD — Positive supply voltage (2.0V to 6.0V) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / Clock output |
| Pin 16 | OSC1/CLKIN — Oscillator input / External clock input |
| Pin 17 | RA0 — Port A bit 0 |
| Pin 18 | RA1 — Port A bit 1 |
Typical Applications
PIC16C554T-04/SO is suitable for 6 applications: Consumer Appliance Controllers, LED Lighting Drivers, Automotive Aftermarket Electronics, Sensor Interface Front-Ends, Battery Chargers and Power Management, Remote Control and Keypad Decoders.
Consumer Appliance Controllers
The PIC16C554T-04/SO fits low-cost appliance controllers (rice cookers, fans, coffee makers) where its 896B OTP memory holds fixed firmware, 13 I/O pins drive relays and read keypads, and the 18-SOIC footprint minimizes PCB area. Its 4MHz core (5 MIPS at 5V) is sufficient for thermostat control, timer sequencing, and LED-indicator multiplexing. Brown-out reset prevents corrupted state during power dips common in motor-driven appliances.
Recommended
LED Lighting Drivers
The PIC16C554T-04/SO can PWM-drive LED strings and matrix displays via its 13 I/O pins and 8-bit timer. At 4MHz, it generates software-PWM frequencies above 1kHz (flicker-free for video) with sufficient resolution for dimming. The 80-byte RAM and 896B program memory accommodate lookup tables for color-mixing algorithms. Its 2-6V operating range suits both battery-powered LED strips and 5V mains-powered fixtures.
Recommended
Automotive Aftermarket Electronics
Automotive aftermarket modules (alarm key fobs, gauge clusters, window controllers) use the PIC16C554T-04/SO for its OTP code security, compact 18-SOIC footprint, and 13 I/O pins. The -04I (industrial) variant is preferred for under-dash use where temperatures reach 70C+ in summer. Brown-out reset and watchdog timer handle automotive electrical transients. OTP memory prevents unauthorized firmware cloning of security-sensitive modules.
Recommended
Sensor Interface Front-Ends
The PIC16C554T-04/SO serves as a low-cost sensor conditioning MCU for thermistors, photo-diodes, and switch contacts. Its 13 I/O pins interface multiple sensors while the 8-bit ADC (where present in the family) digitizes analog readings. The 200 ns instruction cycle delivers sub-microsecond response for switch-debounce and pulse-counting applications. Operating from 2-6V allows direct 3.3V Li-ion battery operation.
Recommended
Battery Chargers and Power Management
Simple NiCd/NiMH chargers and DC-DC control loops fit the PIC16C554T-04/SO. Its 4MHz core executes PWM control algorithms for current/voltage regulation, while 13 I/O pins drive MOSFET gates and read voltage dividers. Brown-out reset prevents over-discharge damage. OTP memory locks the charging profile, eliminating field tampering concerns. Total BOM stays under $2 for the controller section.
Recommended
Remote Control and Keypad Decoders
The PIC16C554T-04/SO implements low-cost IR remote receivers and keypad matrix decoders. Its interrupt-on-change feature detects button presses without polling, freeing the 4MHz core for protocol decoding. With 896B of program memory, NEC RC5/RC6 or proprietary protocols fit comfortably. The 18-SOIC package is small enough for in-wall switch plates and handheld remotes.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C554T-04/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C554-04/SO | PIC16C554T-04I/SO | PIC16C554-04I/SO | PIC16C554-04E/SO |
|---|---|---|---|---|---|
| Package | 18-SOIC (T&R) | 18-SOIC (tube) - same footprint | 18-SOIC (T&R) - same footprint | 18-SOIC (tube) - same footprint | 18-SOIC (tube) - same footprint |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory (bytes) | 896 | 896 | 896 | 896 | 896 |
| RAM (bytes) | 80 | 80 | 80 | 80 | 80 |
| Max Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Operating Temperature | 0C to +70C (commercial) | 0C to +70C | -40C to +85C (industrial) | -40C to +85C (industrial) | 0C to +70C (commercial) |
| I/O Pins | 13 | 13 | 13 | 13 | 13 |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM |
| Shipping Carrier | Tape & Reel | Tube | Tape & Reel | Tube | Tube |
Key Differentiators
- Tape-and-reel carrier for high-volume SMD production (vs PIC16C554-04/SO)
- Industrial temperature range option available in same package (vs PIC16C554T-04I/SO)
- 35-instruction RISC core delivers 5 MIPS at 4 MHz (vs PIC16F54-I/SO)
Design Notes
Estimated: At 5V supply and 4 MHz with all I/O floating, the PIC16C554T-04/SO draws approximately 2-5 mA active. Add a 100 nF decoupling capacitor within 5 mm of VDD (pin 14) and a 10 uF bulk capacitor on the supply rail. Brown-out reset (BOR) is enabled by configuration bits and triggers at approximately 4.0V on a 5V system - leave this enabled to prevent code execution from corrupted memory during supply dips common in relay-driven loads.
Place the decoupling capacitor (100 nF X7R ceramic) within 5 mm of the VDD pin with a short, wide trace to the ground plane. The 18-SOIC package has a center GND pin (pin 5) - connect pin 5 directly to the ground plane with at least 2 vias for low-impedance return. Keep the oscillator traces (OSC1/OSC2) short and surrounded by ground to reduce EMI pickup that could disrupt the internal timing.
OTP memory cannot be erased or rewritten - any firmware bug requires physical chip replacement. For development, use PIC16F54-I/SO (flash) with identical 18-SOIC pinout. The MCLR pin (pin 4) is bidirectional - if left unconnected, it may float and cause spurious resets; tie to VDD via a 10 kohm resistor or drive directly. Configuration bits (oscillator type, watchdog, code protect) must be set during programming - 'default' configuration may not match your design.
Keep I/O traces short and avoid running them parallel to clock or switching signals. Use a ground pour on the bottom layer for return paths. For noisy environments (motor drives, relays), add a ferrite bead or 10 ohm resistor in series with VDD plus a TVS diode at the board input. The 18-SOIC pad pitch is 1.27 mm - hand-solderable but verify thermal pad requirements per IPC-J-STD-020 for reflow profiles.
Compliance Information
Compliance status not explicitly stated in verified web data. Microchip publishes detailed compliance certificates on their product page; refer to PIC16C554 product page for current RoHS/REACH status. Industrial -I suffix typically implies full Pb-free/RoHS compliance, while commercial-grade may require check on the specific date/lot code.
