PIC16C554-20I/SO - 8-Bit 20MHz OTP MCU 18-SOIC | Microchip
MPN: PIC16C554-20I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.34 | $2.34 |
| 10 | $2.1 | $21.00 |
| 100 | $1.92 | $192.00 |
| 500 | $1.74 | $870.00 |
| 1,000 | $1.55 | $1,550.00 |
PIC16C554-20I/SO Overview
An 8-bit microcontroller (MCU) is a small, self-contained computer-on-a-chip that combines a CPU, RAM, non-volatile program memory, and I/O peripherals in a single package. Within the broader IC taxonomy, an 8-bit MCU sits below 32-bit MCUs and microprocessors, but remains dominant in cost-sensitive, deterministic, low-power embedded applications where bit-manipulation efficiency and predictable interrupt latency matter more than raw throughput. The PIC16C5x family was Microchip's first-generation baseline architecture, evolving into the modern PIC16F and PIC18 families still in volume production today.
Key features include 13 digital I/O pins, a 12-bit timer/counter (TMR0) with optional external gate, power-on reset (POR), a watchdog timer (WDT) with its own on-chip RC oscillator, and an 8-bit prescaler shared between the timer and watchdog. The OTP program memory enables one-time field programmability, which historically targeted high-volume production runs where mask-ROM economics outweighed flash reprogrammability. The 35 single-word instruction set reduces learning curves for new firmware developers.
Typical applications span automotive body controllers, industrial sensor interfaces, simple appliance controls, security alarm panels, low-end consumer electronics, IR remote control transmitters, and battery-powered metering. Designers continue to specify the PIC16C554 in legacy designs because of its long product life, mature toolchain (MPLAB, MPASM, C compilers), and pin-compatible Flash replacements like PIC16F54 and PIC16F57.
When migrating firmware, note that the PIC16C554's 12-bit instruction width and 33-instruction opcode are NOT binary-compatible with later PIC16F1xxx or PIC18 instruction sets; assembly source requires rewriting. For new designs, prefer the flash-based PIC16F54 / PIC16F57 family unless OTP cost advantage is decisive.
Drop-in alternatives for PIC16C554-20I/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 PIC16C554-20I/SO (same form factor and footprint) — differing in Package, Core Architecture, Instruction Cycle Time, Program Memory Size, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F54-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C554T-20I/SO
✅ Drop-In✓ In Stock
$1.82 / Unit
View Datasheet →PIC16C554-20E/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C554-04I/SO
✅ Drop-In✓ In Stock
$1.68 / Unit
View Datasheet →PIC16C54C-04I/SO
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC16C54A-04I/SO
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC16C558-20I/SO
✅ Drop-In✓ In Stock
$1.2 / Unit
View Datasheet →PIC16C554-20I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16C 8-bit RISC |
| Instruction Set Width | 12-bit |
| Instruction Count | 35 single-word instructions |
| Maximum Clock Frequency | 20 MHz |
| Instruction Execution Time | 200 ns |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 896 bytes (512 x 14) |
| Data RAM | 80 bytes |
| Data EEPROM | Not present |
| I/O Pins | 13 |
| Timers | 1 x 8-bit TMR0 |
| Watchdog Timer | Yes, with dedicated RC oscillator |
| Operating Voltage | 3.0 V to 5.5 V |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Package | 18-pin SOIC (SO), 7.50 mm body width |
| Mounting Type | Surface Mount (Gull Wing) |
| RoHS Status | Compliant |
PIC16C554-20I/SO Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O pin / digital input |
| Pin 2 | RA3 — Bidirectional I/O pin / digital input |
| Pin 3 | T0CKI/RA4 — Bidirectional I/O pin / Timer0 clock input |
| Pin 4 | /MCLR — Master Clear (reset) input, active low |
| Pin 5 | VSS — Ground reference |
| Pin 6 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 7 | OSC2/CLKOUT — Oscillator crystal output / clock output (Fosc/4) |
| Pin 8 | RC0 — Bidirectional I/O pin |
| Pin 9 | RC1 — Bidirectional I/O pin |
| Pin 10 | RC2 — Bidirectional I/O pin |
| Pin 11 | RC3 — Bidirectional I/O pin |
| Pin 12 | RC4 — Bidirectional I/O pin |
| Pin 13 | RC5 — Bidirectional I/O pin |
| Pin 14 | RC6 — Bidirectional I/O pin |
| Pin 15 | RC7 — Bidirectional I/O pin |
| Pin 16 | VDD — Positive supply voltage (3.0 V to 5.5 V) |
| Pin 17 | RB0/INT — Bidirectional I/O pin / external interrupt input |
| Pin 18 | RB1 — Bidirectional I/O pin |
Typical Applications
PIC16C554-20I/SO is suitable for 6 applications: Automotive Body Controllers, Industrial Sensor Interfaces, Appliance Control Boards, Security Alarm Panels, IR Remote Control Transmitters, Battery-Powered Metering.
Automotive Body Controllers
The PIC16C554-20I/SO fits automotive body controller networks because of its industrial temperature rating (-40 C to +85 C), 20 MHz deterministic 200 ns instruction cycle, and 13 general-purpose I/O that can drive relays and read switches directly. Its 12-bit instruction set with 35 single-word opcodes yields compact, predictable code for door-lock, mirror-control, and wiper-control ECUs. The 896-byte OTP holds typical 600-800 line assembly modules, and the on-chip watchdog timer with dedicated RC oscillator protects against software lock-up in noisy automotive environments. Compared to a flash MCU, the OTP one-time-program nature suits high-volume body controllers where firmware revision is locked after PPAP, and the 18-SOIC footprint allows surface-mount assembly compatible with existing wave-solder production lines.
Recommended
Industrial Sensor Interfaces
The PIC16C554-20I/SO is well suited to industrial sensor interface modules such as proximity sensors, photoelectric switches, and simple 4-20 mA loop conditioners because its 20 MHz clock handles 50 kHz signal processing tasks while the 12-bit PIC16C5x instruction set produces tight, deterministic interrupt response for time-critical sensor sampling. The 13 I/O pins support multiple sensor channels plus status LEDs, and the TMR0 8-bit timer with prescaler simplifies period measurement. The industrial -40 C to +85 C operating range covers factory-floor ambient, and the 18-SOIC package allows compact IP67 sensor housings. Compared to a 32-bit Cortex-M0 alternative, the PIC16C554 is dramatically cheaper and lower-power, and its OTP memory fits the locked-firmware production model typical of sensor end products.
Recommended
Appliance Control Boards
The PIC16C554-20I/SO is widely used in white-goods and small appliance control boards - washing machines, microwave ovens, dishwashers, and air-conditioner remotes - because of its low unit cost, 5 V operation from rectified mains, and proven reliability in long-life consumer products. Its 35-instruction RISC core produces 600-1000 line assembly programs that easily fit within the 896-byte OTP budget. The 8-bit TMR0 with watchdog supports both motor-control PWM generation and software lock-up recovery, while the 13 I/O handle keypad scanning, triac drive, LED indication, and buzzer tones. Compared to newer flash MCUs, the PIC16C554's OTP structure is more cost-effective at >50K annual volume where the mask-style programming amortizes across the product lifecycle.
Recommended
Security Alarm Panels
The PIC16C554-20I/SO serves as the main controller in PIR motion-detector alarm panels and wired security keypads because of its fast interrupt response, low power consumption, and 13 I/O that accommodate PIR sensor input, tamper switch, reed relay output, and 7-segment status LEDs. The on-chip watchdog timer with dedicated RC oscillator catches firmware lock-up that would otherwise disable a security system. The 20 MHz clock supports periodic loop times below 5 ms, ensuring alarm-zone sampling meets UL 1023 timing requirements. OTP memory prevents firmware reverse-engineering by competitors, a security advantage over flash-based parts in commercial alarm deployments. Compared to a 32-bit MCU, the PIC16C554 costs less than $2 at 1000 pieces and runs from a single 5 V rail.
Recommended
IR Remote Control Transmitters
The PIC16C554-20I/SO is ideal for IR remote control transmitters (TV, set-top box, audio receiver, projector) because of its 20 MHz clock that generates accurate 38 kHz / 56 kHz carrier frequencies for NEC, RC5, and SIRC protocols, and its 13 I/O accommodate a 4x4 key matrix plus status LED. The 12-bit instruction set with 35 single-word opcodes enables compact 200-400 line IR-protocol firmware within the 896-byte OTP budget. Low power consumption (under 2 mA active, <1 uA sleep with WDT enabled) supports 2x AAA battery operation. Compared to a 32-bit MCU, the PIC16C554 dramatically extends battery life and reduces BOM cost below $1.50 in volume, making it the workhorse of consumer IR remotes for >25 years.
Recommended
Battery-Powered Metering
The PIC16C554-20I/SO is used in battery-powered metering devices (water meters, gas meters, simple electricity meters) because of its low 2 mA active current, sub-1 uA sleep current with watchdog enabled, and 13 I/O for pulse-input sensors, LCD drive, and tamper detection. The 8-bit TMR0 accurately counts low-frequency pulse trains from reed switches or Hall sensors. The industrial -40 C to +85 C range covers outdoor meter housings, and the OTP memory prevents consumer-side firmware tampering - a regulatory concern in utility metering. Compared to a Cortex-M0 with 32 kHz RTC, the PIC16C554 achieves 5+ year battery life on 2x AA cells in typical metering duty cycles while costing less than $2 per unit at volume.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C554-20I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F54-I/SO | PIC16C554T-20I/SO | PIC16C554-20E/SO | PIC16C554-04I/SO | PIC16C558-20I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC (SO) | 18-SOIC (SO) - same | 18-SOIC (SO) - same | 18-SOIC (SO) - same | 18-SOIC (SO) - same | 18-SOIC (SO) - same |
| Program Memory Type | OTP | Flash (reprogrammable) | OTP (same) | OTP (same) | OTP (same) | OTP (same) |
| Program Memory Size | 896 bytes (512 x 14) | 896 bytes (same) | 896 bytes (same) | 896 bytes (same) | 896 bytes (same) | 2048 bytes (1024 x 14) |
| Maximum Clock Frequency | 20 MHz | 20 MHz (same) | 20 MHz (same) | 20 MHz (same) | 4 MHz (-80%) | 20 MHz (same) |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +85 C (same) | -40 C to +85 C (same) | -40 C to +125 C (Extended) | -40 C to +85 C (same) | -40 C to +85 C (same) |
| I/O Pins | 13 | 13 (same) | 13 (same) | 13 (same) | 13 (same) | 13 (same) |
| Data RAM | 80 bytes | 80 bytes (same) | 80 bytes (same) | 80 bytes (same) | 80 bytes (same) | 128 bytes (+60%) |
| Watchdog Timer | Yes (dedicated RC) | Yes (same) | Yes (same) | Yes (same) | Yes (same) | Yes (same) |
Key Differentiators
- Flash-based reprogrammability vs. one-time-program (vs PIC16F54-I/SO)
- Industrial temperature grade availability (vs PIC16C554-20I/SO vs. PIC16C554-20I/P)
- Higher 20 MHz clock grade for time-critical code (vs PIC16C554-04I/SO)
Design Notes
The PIC16C554-20I/SO operates from a single 3.0 V to 5.5 V supply on VDD (pin 16). Place a 0.1 uF ceramic decoupling capacitor as close as physically possible to the VDD pin, with a 10 uF electrolytic or tantalum bulk capacitor on the same rail. The /MCLR reset pin should be tied to VDD through a 10 kohm pull-up resistor to ensure clean power-on reset behavior; adding a 0.1 uF capacitor on /MCLR improves noise immunity in electrically noisy environments such as automotive and industrial installations.
PIC16C554 OTP memory is one-time programmable - every code revision requires a new part. For new designs with revision cycles, choose PIC16F54-I/SO instead; for legacy lock-firmware production where revision is not expected, PIC16C554 remains a cost-effective option. Engineers migrating code from PIC16C54 or PIC16C56 to PIC16C554 must verify I/O mapping: PIC16C554 has 13 I/O (RA0-RA4, RB0-RB7, RC0-RC7) but pin assignments differ from older family members. Source code must be recompiled - PIC16C554 is NOT binary-compatible with PIC16F1xxx or PIC18 instruction sets.
Estimated: at 20 MHz active current and 5 V supply, the PIC16C554-20I/SO dissipates approximately 50 mW (10 mA typical active). The 18-SOIC package has a theta_JA of approximately 85 C/W (estimated based on SOIC family data). At industrial upper limit 85 C ambient, junction temperature rises only 4.25 C - well within the 150 C max junction. No heatsink required for any commercial or industrial application. Ensure PCB copper pour area around the SOIC pads meets minimum 50 sq mm thermal relief guidelines.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified; for automotive applications requiring AEC-Q100, consider PIC16F54-I/SO automotive grade. Industrial temperature grade (-40 C to +85 C) per 'I' suffix.
