PIC16C554T-20I/SO - 8-Bit 20MHz OTP MCU, 896B, 18-SOIC | Microchip
MPN: PIC16C554T-20I/SO β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.56 | $25.60 |
| 100 | $2.28 | $228.00 |
| 500 | $2.04 | $1,020.00 |
| 1,000 | $1.82 | $1,820.00 |
PIC16C554T-20I/SO Overview
What is an OTP microcontroller? An OTP (One-Time Programmable) microcontroller contains non-volatile program memory that can be written exactly once by the user, typically using a device programmer before PCB mounting. OTP MCUs sit between Mask ROM devices (cheapest at very high volumes but require factory programming) and Flash-based MCUs (re-programmable in-circuit). For low-to-medium volume production, OTP parts offer lower per-unit cost than Flash parts without the tooling NRE of Mask ROM.
Key features include a RISC instruction set with only 33 single-word instructions, two 8-bit I/O ports (RA and RC), one 8-bit timer (TMR0), a watchdog timer with its own on-chip RC oscillator, power-on reset, brown-out detection, and an operating voltage range from 2.5 V to 5.5 V. The PIC16C5x baseline core has no hardware interrupt controller and uses a polled software architecture.
The device uses a Harvard architecture with separate program and data buses, executing one instruction per instruction cycle (4 oscillator clocks) for a 200 ns instruction time at 20 MHz. This deterministic single-cycle execution makes the PIC16C554 well-suited for real-time control loops where precise timing matters. The baseline core has a 2-level deep hardware stack and no software stack pointer.
Typical applications include appliance control, sensor signal conditioning, LED lighting controllers, simple motor control, remote controls, battery-powered instruments, and automotive body electronics (non-safety). The industrial temperature range and small 18-SOIC footprint suit dense control boards.
When designing with this part, note that OTP memory means firmware must be fully verified before programming. Allow for a programming connector footprint (ICSP) on the PCB if in-system verification is required during pilot runs. Always place a 0.1 uF decoupling capacitor within 5 mm of the VDD pin.
Drop-in alternatives for PIC16C554T-20I/SO β 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-20I/SO (same form factor and footprint) β differing in Package, Program Memory Size, Timers, Core Architecture, Family.
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Request AlternativesPIC16C554T-20I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16C5x baseline (8-bit RISC) |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 896 bytes (512 x 14 bits) |
| Data RAM | 80 bytes |
| Maximum CPU Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns (1 cycle = 4 oscillator clocks) |
| Operating Voltage (VDD) | 2.5 V to 5.5 V |
| I/O Pins | 13 (PORTA 4-bit + PORTC 8-bit) |
| Timers | 1 x 8-bit (TMR0) + 1 x WDT |
| Package | 18-SOIC (7.50 mm body width) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | -40C to +85C (Industrial, I-suffix) |
| Speed Grade | -20 (20 MHz oscillator max) |
| Packaging | Tape & Reel (T-suffix) |
| RoHS Status | Compliant |
PIC16C554T-20I/SO Pin Configuration
| Pin 1 | RA2 β Bidirectional I/O pin, PORTA bit 2 |
| Pin 2 | RA3 β Bidirectional I/O pin, PORTA bit 3 |
| Pin 3 | RA4/T0CKI β PORTA bit 4 / Timer0 clock input (open-drain) |
| Pin 4 | MCLR/VPP β Master clear reset (active low) / programming voltage input |
| Pin 5 | VSS β Ground reference |
| Pin 6 | OSC1/CLKIN β Oscillator crystal input / external clock input |
| Pin 7 | OSC2/CLKOUT β Oscillator crystal output / clock output (Fosc/4) |
| Pin 8 | RC0 β Bidirectional I/O pin, PORTC bit 0 |
| Pin 9 | RC1 β Bidirectional I/O pin, PORTC bit 1 |
| Pin 10 | RC2 β Bidirectional I/O pin, PORTC bit 2 |
| Pin 11 | RC3 β Bidirectional I/O pin, PORTC bit 3 |
| Pin 12 | RC4 β Bidirectional I/O pin, PORTC bit 4 |
| Pin 13 | RC5 β Bidirectional I/O pin, PORTC bit 5 |
| Pin 14 | RC6 β Bidirectional I/O pin, PORTC bit 6 |
| Pin 15 | RC7 β Bidirectional I/O pin, PORTC bit 7 |
| Pin 16 | VDD β Positive supply voltage (2.5 V to 5.5 V) |
| Pin 17 | RA0 β Bidirectional I/O pin, PORTA bit 0 |
| Pin 18 | RA1 β Bidirectional I/O pin, PORTA bit 1 |
Typical Applications
PIC16C554T-20I/SO is suitable for 7 applications: Appliance Control Board, LED Lighting Controller, Battery-Powered Sensor Interface, Remote Control Transmitter, Simple Motor Speed Control, Automotive Body Electronics, Industrial Control Logic Replacement.
Appliance Control Board
The PIC16C554T-20I/SO fits appliance control boards because its 20 MHz PIC16C5x baseline core delivers deterministic 200 ns instruction cycles ideal for washing-machine motor timing loops and dishwasher cycle sequencing. Its 896-byte OTP memory holds a complete wash-program state machine with parameter tables; the 80-byte RAM accommodates sensor buffers and timer variables for water level, temperature, and door-lock state. The wide 2.5 V to 5.5 V VDD range tolerates unregulated supply rails common in white-goods designs, while the -40 C to +85 C industrial temperature rating covers under-counter and outdoor-utility installations. PIC16C554T-20I/SO pairs well with ULN2003A relay drivers and zero-cross solid-state relays for heater and motor switching.
Recommended
LED Lighting Controller
For LED lighting drivers and color-mixing controllers, the PIC16C554T-20I/SO's 20 MHz CPU provides sufficient throughput for PWM generation across multiple channels using software bit-banging on PORTC. The 80-byte RAM supports a color-lookup table and PWM duty-cycle buffers for RGB or RGBW strips, while the 13 digital I/O pins drive 8 LED channels plus user-interface buttons. The 2.5 V to 5.5 V operating range matches battery-powered and USB-powered LED fixtures, and the industrial temperature range allows installation in outdoor or enclosed luminaires. Brown-out reset protects LEDs from inrush flicker when power sags during dimming transitions.
Recommended
Battery-Powered Sensor Interface
The PIC16C554T-20I/SO suits battery-powered sensor nodes thanks to its sleep-friendly 8-bit baseline core that drops current draw when the watchdog-timer wakes the MCU for periodic sensor reads. The 80-byte RAM buffers sensor samples for averaging before transmission, and the 13 I/O pins multiplex several analog sensors via external analog multiplexers or discrete FETs. Operating down to 2.5 V extends usable battery life from alkaline or Li-primary cells below their nominal voltage, while the -40 C to +85 C range covers outdoor environmental sensors. The 200 ns instruction cycle at 20 MHz executes simple protocol stacks (UART, one-wire) in real time.
Recommended
Remote Control Transmitter
For IR/RF remote controls and key-fob transmitters, the PIC16C554T-20I/SO's small 18-SOIC footprint fits compact handheld enclosures while its 896-byte OTP memory stores button-scan tables and rolling-code transmission routines. The 20 MHz clock drives accurate 38 kHz IR carrier generation via timer interrupts, and the 13 I/O pins support up to 12-button matrix keyboards plus status LEDs. Brown-out detection prevents corrupted transmissions when battery voltage sags during button presses. The -40 C to +85 C industrial range handles outdoor or automotive interior environments.
Recommended
Simple Motor Speed Control
The PIC16C554T-20I/SO controls small DC brush motors and unidirectional fans using its 8-bit TMR0 for back-EMF or tachometer feedback and software-based PWM on PORTC pins. The 80-byte RAM holds RPM setpoint, current speed, and PID state variables, while the 200 ns instruction cycle at 20 MHz executes a PID loop at kHz rates. The 2.5 V to 5.5 V VDD range supports 3.3 V and 5 V motor-driver boards. Industrial temperature rating suits automotive accessory fans and HVAC blowbox controllers.
Recommended
Automotive Body Electronics
For non-safety automotive body modules such as seat controllers, mirror adjusters, and interior lighting, the PIC16C554T-20I/SO delivers a cost-optimized 8-bit solution in the 18-SOIC package. The -40 C to +125 C automotive temperature range (note: I-suffix is -40 to +85 C; for +125 C use E-suffix parts) covers cabin environments, and the 13 I/O pins interface to H-bridge drivers and switch-scan matrices. The 20 MHz CPU handles CAN-like software bit-banging for body networks, and the OTP memory locks firmware against field tampering.
Recommended
Industrial Control Logic Replacement
The PIC16C554T-20I/SO replaces legacy discrete logic or 8051-based designs where cost reduction and footprint shrink are priorities. Its 20 MHz PIC16C5x core executes simple ladder-logic replacements, and the 13 I/O pins sink 25 mA per pin directly, driving small relays and optocouplers without external buffers. Industrial temperature range plus the 2.5 V to 5.5 V supply tolerance suit 24 V industrial systems with simple linear regulators. OTP memory prevents firmware modification in deployed equipment.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C554T-20I/SO β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C554-20I/SO | PIC16C554T-20/SO | PIC16C554T-04I/SO | PIC16F54-I/SO |
|---|---|---|---|---|---|
| Package | 18-SOIC (7.50 mm) | 18-SOIC (7.50 mm) - same | 18-SOIC (7.50 mm) - same | 18-SOIC (7.50 mm) - same | 18-SOIC (7.50 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | OTP (896 B) | OTP (896 B) | OTP (896 B) | OTP (896 B) | Flash (768 B) |
| Max CPU Frequency | 20 MHz | 20 MHz | 20 MHz | 4 MHz | 20 MHz |
| Data RAM | 80 bytes | 80 bytes | 80 bytes | 80 bytes | 25 bytes |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +85 C | 0 C to +70 C (Commercial) | -40 C to +85 C | -40 C to +85 C |
| Operating Voltage | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.0 V to 5.5 V |
| I/O Pins | 13 | 13 | 13 | 13 | 12 |
| Reprogrammable | No (OTP) | No (OTP) | No (OTP) | No (OTP) | Yes (Flash) |
Key Differentiators
- Higher data RAM than Flash-based PIC16F54 equivalent (vs PIC16F54-I/SO)
- Lower per-unit cost than Flash equivalents at high volumes (vs PIC16F54-I/SO)
- Same-package drop-in at 20 MHz speed grade (vs PIC16C554T-04I/SO)
Design Notes
Place a 0.1 uF ceramic decoupling capacitor within 5 mm of the VDD pin (pin 16) and a 10 uF bulk capacitor on the same supply rail near the IC. The PIC16C554 brown-out reset (BOR) circuit holds the device in reset when VDD drops below the BOR threshold (~2.1 V to 2.4 V typical), preventing corrupted execution at low voltage. Estimated: at 20 MHz with all I/O switching, peak VDD current draw is roughly 10-15 mA; average is lower because the core sleeps in idle loops.
Keep the MCLR/VPP pin (pin 4) free of large capacitance - the in-circuit serial programming (ICSP) pulses a high voltage (around 13 V) on this pin during device programming. A 10 kohm pull-up resistor to VDD and a decoupling capacitor of 0.1 uF or less is typical. If using a crystal oscillator, place the crystal within 5 mm of pins 6 and 7 and guard the traces with a ground pour to reduce EMI.
OTP memory cannot be re-programmed - any code bug found after programming requires scrapping the part. Plan a prototype run with PIC16F54-I/SO (pin-compatible Flash equivalent in 18-SOIC) for development, then move to PIC16C554T-20I/SO for production. Also note that the PIC16C5x baseline core has NO interrupts - all event handling is polled via register flags, which affects firmware architecture.
At 20 MHz and 5 V supply, the PIC16C554T-20I/SO dissipates approximately 50-75 mW worst case. With the 18-SOIC package theta_JA around 70 C/W, junction temperature rises 4-5 C above ambient at typical office temperatures - well within the 150 C absolute maximum. No heatsink or thermal management is required for normal operation. Estimated using I/O toggling and core active current from datasheet.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified (industrial-grade I-suffix, not automotive Q-grade). Lead-free (Pb-free) reflow compatible per JEDEC J-STD-020.
