PIC16C554-20I/SS - 8-bit OTP MCU, 20MHz, SSOP-20 | Microchip
MPN: PIC16C554-20I/SS ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.57 | $25.70 |
| 100 | $2.28 | $228.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.82 | $1,820.00 |
PIC16C554-20I/SS Overview
An 8-bit OTP (One-Time Programmable) microcontroller is a non-flash, EPROM-based variant of the popular PIC architecture. OTPs sit in the product hierarchy as: microcontroller -> embedded MCU -> 8-bit MCU -> PIC16C5x family. OTP parts are typically chosen for cost-sensitive, high-volume, stable-firmware applications where the program code is finalized and field re-programmability is not required. Compared with Flash-based PIC16F equivalents, OTP devices are usually lower cost per unit and offer slightly better long-term data retention, at the expense of no in-circuit reprogrammability.
Key features include a 20 MHz maximum oscillator frequency, 200 ns instruction execution time, 8-bit timer/counter with 8-bit prescaler, watchdog timer with dedicated on-chip RC oscillator, power-on reset, power-saving SLEEP mode, and programmable code protection. The 13 I/O pins support individual direction control and direct LED drive capability (25 mA sink/source per pin), eliminating external driver transistors in many designs.
The PIC16C554-20I/SS uses a Harvard-architecture RISC core with separate program and data buses. Its 12-bit instruction word (PIC16C5x baseline family) provides efficient encoding and deterministic timing. The device operates from 2.5V to 5.5V, and the SSOP-20 (5.30 mm body) package supports surface-mount assembly in compact consumer, industrial, and appliance form factors.
Typical applications include appliance controllers (washing machines, microwave ovens, coffee makers), battery chargers, remote controls, small motor control, security panels, and low-cost sensor signal-conditioning front ends. The wide operating voltage range and robust I/O drive make it well-suited to white-goods and HVAC subsystems where BOM cost dominates.
When designing with this part, note that OTP memory cannot be reprogrammed - firmware bugs discovered after programming cannot be fixed without a new device. For prototypes or designs requiring firmware iteration, choose the Flash-based PIC16F54 or PIC16F57 in the same SSOP-20 footprint instead. A 4 kHz to 20 MHz oscillator or resonator is required, and decoupling must be placed within 1 cm of VDD.
This page synthesizes distributor inventory, parametric drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC16C554-20I/SS — 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/SS (same form factor and footprint) — differing in Package, Program Memory Size, Program Memory Type, Timers, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C54C-20I/SS
✅ Drop-In✓ In Stock
$1.74 / Unit
View Datasheet →PIC16C55-10I/SS
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC16C54A-20I/SS
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.51 / Unit
View Datasheet →PIC16C54CT-20I/SO
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$0.95 / Unit
View Datasheet →PIC16F54-I/SS
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
PIC16C554-20I/SS Maximum Ratings & Electrical Characteristics
| Family | PIC16C5x |
| Core | 8-bit PIC RISC |
| Program Memory Type | EPROM (OTP) |
| Program Memory Size | 896 bytes (0.875 KB) |
| RAM | 80 bytes |
| EEPROM | 0 bytes |
| Maximum CPU Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns |
| Instruction Set Size | 35 single-word instructions |
| I/O Pins | 13 |
| Timers | 1 x 8-bit (TMR0 with 8-bit prescaler) |
| Watchdog Timer | Yes (with on-chip RC oscillator) |
| Supply Voltage (VDD) | 2.5 V to 5.5 V |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Package | 20-pin SSOP (5.30 mm body) |
| Mounting Type | Surface Mount (Gull Wing) |
| I/O Sink/Source Current | 25 mA per pin |
| Power-on Reset | Yes |
| SLEEP Mode | Yes |
| Code Protection | Programmable |
| RoHS Status | Compliant |
PIC16C554-20I/SS Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O port A bit 2 |
| Pin 2 | RA3 — Bidirectional I/O port A bit 3 |
| Pin 3 | T0CKI — Timer0 clock input (also RA4) |
| Pin 4 | MCLR — Master Clear reset input (active low) |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0 — Bidirectional I/O port B bit 0 (interrupt on change) |
| 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 | VSS — Ground reference |
| Pin 15 | OSC2 — Oscillator output (crystal/ceramic/resistor mode) |
| Pin 16 | OSC1 — Oscillator input |
| Pin 17 | RA0 — Bidirectional I/O port A bit 0 |
| Pin 18 | RA1 — Bidirectional I/O port A bit 1 |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | VDD — Positive supply voltage (2.5 V to 5.5 V) |
Typical Applications
PIC16C554-20I/SS is suitable for 6 applications: White Goods Appliance Control, Remote Control and IR Transmitter, Battery Charger Controller, Security Panel and Alarm Sensor, Small Motor Speed Control, Sensor Signal Conditioning Front End.
White Goods Appliance Control
The PIC16C554-20I/SS fits white-goods appliance controllers such as washing machines, dishwashers, and microwave ovens where BOM cost dominates and firmware is locked at production. Its 13 I/O pins with 25 mA direct drive capability can sink segment-LCD backlight current and relay coils without external transistors, while the 896-byte EPROM holds the full state machine for cycle sequencing. Operating from 2.5 V to 5.5 V at -40 C to +85 C industrial grade, the device tolerates the wide supply and thermal swings inside a household appliance. The 20 MHz CPU executes one instruction every 200 ns, sufficient for sensor sampling at 1 kHz plus relay debounce logic in parallel.
Recommended
Remote Control and IR Transmitter
The PIC16C554-20I/SS is well suited for handheld IR remote controls, where its <1 uA SLEEP current extends battery life for years on a single coin cell. The 13 I/O pins can matrix-scan up to a 3x4 keypad with dedicated IR-LED driver output; the 25 mA source capability directly drives the IR transmitter without an external FET. EPROM-based OTP storage locks the protocol code at production time, preventing firmware tampering. The 20 MHz instruction cycle gives precise 38 kHz carrier timing with sub-microsecond resolution, critical for NEC, RC5, and Sony SIRC IR protocol compliance.
Recommended
Battery Charger Controller
In linear NiMH or lead-acid battery chargers, the PIC16C554-20I/SS provides the supervisory control loop, monitoring voltage and temperature while PWM-driving a MOSFET pass element. Its 25 mA I/O sink current can directly drive opto-isolators or small MOSFET gates up to 1 A peak. The wide 2.5-5.5 V operating range supports single-cell LiFePO4 packs through to 6 V SLA banks with the same firmware. With <1 uA SLEEP current and a wake-on-timer option via watchdog overflow, the part can spend most of its life in standby, only waking every few seconds to sample cell voltage.
Recommended
Security Panel and Alarm Sensor
Security-system peripherals such as PIR motion detectors, door/window sensors, and keypad decoders benefit from the PIC16C554-20I/SS's 13 I/O and low power characteristics. The watchdog timer with dedicated internal RC oscillator provides autonomous reset capability independent of external components, ensuring the sensor recovers from brown-outs or EMI events. EPROM code protection prevents cloning of proprietary alarm protocols. The industrial temperature range supports outdoor enclosures from -40 C winters to +85 C rooftop installations.
Recommended
Small Motor Speed Control
The PIC16C554-20I/SS can drive small brushless DC, brushed DC, or stepper motor controllers in fans, pumps, and small appliances. Its 200 ns instruction cycle supports closed-loop PID computation at 5-10 kHz, fast enough for tachometer feedback on most small motors. The 25 mA I/O source/sink capability can directly drive opto-isolated gate-driver inputs for low-current motor bridges up to 2 A. Industrial temperature grade supports under-hood automotive fan and HVAC damper applications.
Recommended
Sensor Signal Conditioning Front End
Industrial sensor-interface modules for thermocouples, RTDs, strain gauges, and process transmitters can use the PIC16C554-20I/SS as a digital signal conditioner, applying linearization, averaging, and HART-style modulation. With 13 I/O, the device can directly scan multiple analog channels via external multiplexer control lines while dedicating pins to UART, status LEDs, and a calibration pushbutton. The 896-byte EPROM holds lookup tables and calibration coefficients without needing external EEPROM, reducing BOM cost and improving reliability in long-lifecycle industrial installations.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C554-20I/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C54C-20I/SS | PIC16C55-10I/SS | PIC16C54A-20I/SS | PIC16F54-I/SS |
|---|---|---|---|---|---|
| Package | SSOP-20 (5.30 mm) | SSOP-20 - same | SSOP-20 - same | SSOP-20 - same | SSOP-20 - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 896 B EPROM (OTP) | 768 B EPROM (OTP) | 768 B EPROM (OTP) | 512 B EPROM (OTP) | 768 B Flash |
| RAM | 80 B | 80 B | 80 B | 25 B | 25 B |
| Max CPU Frequency | 20 MHz | 20 MHz | 10 MHz | 20 MHz | 20 MHz |
| I/O Pins | 13 | 13 | 13 | 13 | 13 |
| Program Memory Type | EPROM (OTP) | EPROM (OTP) | EPROM (OTP) | EPROM (OTP) | Flash (reprogrammable) |
| Lifecycle Status | NRND | Active | NRND | NRND | Active |
Key Differentiators
- Largest program memory in PIC16C5x SSOP-20 family (vs PIC16C54C-20I/SS)
- Highest performance in PIC16C5x SSOP-20 OTP family (vs PIC16C55-10I/SS)
- Mature, well-documented 8-bit PIC RISC core (vs Generic 8051-core MCU)
Design Notes
Place a 0.1 uF ceramic decoupling capacitor within 10 mm of the VDD pin (pin 20) and a bulk 10 uF tantalum or aluminum capacitor near the package. For designs operating below 3.3 V, add a 100 nF capacitor in parallel with VDD to suppress Vcore noise. The PIC16C554-20I/SS includes internal power-on reset; however, an external brown-out circuit is recommended for industrial 24V-derived rails with wide tolerance.
OTP memory cannot be erased or rewritten - any firmware bug discovered after programming requires replacing the device. For development cycles, program samples into a Flash-based PIC16F54-I/SS (same SSOP-20 pinout) and validate firmware before committing to OTP production units. Also note that pin 19 is NC on SSOP-20 but pin 19 on PDIP-18 is OSC2 - the pinout is NOT identical across packages, even from the same Microchip datasheet family.
Keep the oscillator traces (OSC1/OSC2, pins 16/15) short and shield them with a ground guard ring to reduce EMI susceptibility. Place the crystal or ceramic resonator within 5 mm of the OSC pins with symmetrical trace lengths. For HS (high-speed) oscillator mode above 4 MHz, add a 1 MOhm parallel resistor across the crystal to guarantee oscillation startup. Avoid routing high-current switching signals adjacent to the OSC traces.
The SSOP-20 package has a thermal resistance (theta_JA) of approximately 90 C/W on a standard JEDEC 4-layer test board. At maximum operating ambient (85 C) and typical 5 mA active supply current at 5 V (25 mW dissipation), junction temperature rise is approximately 2.3 C - well within the 150 C maximum. The part is not thermally limited in normal SSOP-20 designs.
Compliance Information
RoHS and lead-free compliant per Microchip product page; not AEC-Q100 qualified (industrial -40C to +85C grade only); halogen-free status not explicitly stated in verified data.
