PIC16C54CT-04/SO - 8-Bit 4MHz OTP MCU 768B | Microchip
MPN: PIC16C54CT-04/SO β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.45 | $2.45 |
| 10 | $2.18 | $21.80 |
| 100 | $1.85 | $185.00 |
| 500 | $1.62 | $810.00 |
| 1,000 | $1.41 | $1,410.00 |
PIC16C54CT-04/SO Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (ROM/Flash/OTP), data memory (RAM), and peripheral interfaces into one IC. PIC microcontrollers from Microchip use a Harvard RISC architecture with a small, fixed-length instruction set, which simplifies pipelining and enables deterministic instruction timing. PIC16C5x parts are EPROM/ROM-based; the OTP variant on the PIC16C54C is factory or prototype programmable, contrasting with later PIC16F parts that use Flash memory.
The PIC16C54C runs from 3.0 V to 5.5 V, has a 33-instruction set, 12-bit-wide instructions yielding roughly 2:1 code compression over typical 8-bit CISC MCUs of its era, and supports in-circuit serial programming (ICSP) via dedicated pins. It features a 4 MHz internal-execution rate, watchdog timer with on-chip RC oscillator, power-on reset, and a wide operating temperature range suited to commercial embedded products. A separate PIC16LC54C variant lowers power consumption at reduced clock speeds.
The architecture is a fully static CMOS design, eliminating minimum clock-frequency restrictions and enabling low-power sleep modes. The 12-bit instruction word and 8-bit data path produce compact code, while the 33-instruction set reduces development time. A two-stage pipeline overlaps fetch and execute, and the part is built around a 12-bit program counter that limits direct addressing to 2K words of program memory.
Typical applications include low-cost consumer appliances, simple sensor and motor control nodes, battery chargers, remote controls, intelligent LED drivers, and industrial timers where cost dominates over computational throughput. Because of its 12 I/O pins and modest peripheral set, designers often pair the PIC16C54C with external driver ICs and analog front-ends.
When designing with this part, plan oscillator and reset circuitry carefully: a 4 MHz ceramic resonator with the appropriate load capacitors gives a stable clock, and the MCLR pin needs a proper pull-up reset network. Use ICSP for prototype flashing before committing to the OTP pattern.
This page synthesizes distributor stock and pricing, drop-in PIC16C5x replacements in the same SOIC-18 footprint, and application/design notes drawn from Microchip datasheets that go beyond a single product listing.
Drop-in alternatives for PIC16C54CT-04/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 PIC16C54CT-04/SO (same form factor and footprint) β differing in Package, Program Memory Size, Program Memory Type, Operating Temperature Range, Timers.
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Request AlternativesPIC16C54CT-04/SO Maximum Ratings & Electrical Characteristics
| Core | 8-bit PIC RISC |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 768 B (512 x 12 words) |
| Data RAM | 25 B |
| Maximum Clock Frequency | 4 MHz |
| Instruction Set | 33 instructions, 12-bit wide |
| I/O Pins | 12 |
| Supply Voltage | 3.0 V to 5.5 V |
| Operating Temperature | 0C to +70C (commercial) |
| Package | 18-pin SOIC (SO), 0.295 inch (7.50 mm) body width |
| Mounting Type | Surface Mount, gull-wing leads |
| Architecture | Harvard RISC, fully static CMOS |
| Watchdog Timer | Yes (on-chip RC oscillator) |
| Power-on Reset | Yes |
| In-Circuit Programming | Yes (ICSP) |
| RoHS Status | unknown |
PIC16C54CT-04/SO Pin Configuration
| Pin 1 | RA2 β Bidirectional I/O port A bit 2 |
| Pin 2 | RA3 β Bidirectional I/O port A bit 3 |
| Pin 3 | RB4 β Bidirectional I/O port B bit 4 |
| Pin 4 | RB5 β Bidirectional I/O port B bit 5 |
| Pin 5 | RB6 β Bidirectional I/O port B bit 6 |
| Pin 6 | RB7 β Bidirectional I/O port B bit 7 |
| Pin 7 | VSS β Ground reference |
| Pin 8 | OSC1 β Oscillator input / external clock input |
| Pin 9 | OSC2 β Oscillator output |
| Pin 10 | T0CKI β Timer0 clock input |
| Pin 11 | RB0/INT β Bidirectional I/O port B bit 0, external interrupt |
| Pin 12 | RB1 β Bidirectional I/O port B bit 1 |
| Pin 13 | RB2 β Bidirectional I/O port B bit 2 |
| Pin 14 | RB3 β Bidirectional I/O port B bit 3 |
| Pin 15 | MCLR/VPP β Master clear reset input / programming voltage |
| Pin 16 | RA0 β Bidirectional I/O port A bit 0 |
| Pin 17 | RA1 β Bidirectional I/O port A bit 1 |
| Pin 18 | VDD β Positive supply voltage (3.0-5.5 V) |
Typical Applications
PIC16C54CT-04/SO is suitable for 7 applications: Low-Cost Consumer Appliance Controller, Battery Charger and Power Tool Timer, Remote Control and IR Transmitter, LED Driver and Signage Controller, Industrial Timer and Sequencer, Simple Sensor Hub with External ADC, Educational 8-bit MCU Trainer Board.
Low-Cost Consumer Appliance Controller
The PIC16C54CT-04/SO suits low-cost consumer appliance controllers such as toasters, coffee makers, hair dryers and small kitchen gadgets where cost dominates over compute. Its 12-bit instruction word delivers ~2:1 code compression vs typical 8-bit CISC MCUs, so the 768 B (512 x 12) program memory holds non-trivial state machines for timer, sensor and relay sequencing. The 12 GPIO pins drive LEDs, buttons and TRIAC gates directly, and the 3.0-5.5 V supply matches rectified 5 V rails without extra regulation. Unlike Flash parts, the OTP memory is one-time programmable, so this part is best when the firmware is finalized and high-volume production is the priority.
Recommended
Battery Charger and Power Tool Timer
The PIC16C54CT-04/SO is widely used in lead-acid and NiMH charger controllers and cordless power-tool timer boards where the OTP cost advantage matters. With 25 bytes of RAM and 4 MHz instruction execution, it can service CC/CV charge state machines, ADC-free voltage sense via comparator input, and PWM-driven MOSFET gates for current regulation. The on-chip watchdog timer with internal RC oscillator adds resilience against brownouts in noisy power environments. The industrial-grade sibling PIC16C54CT-04I/SO extends operation to -40C to +85C, suiting outdoor or automotive-trunk applications.
Recommended
Remote Control and IR Transmitter
The PIC16C54CT-04/SO's 4 MHz core and 12 GPIO pins are well-matched to low-cost IR remote controls that emit RC5, NEC, or proprietary protocols. Its 33-instruction set and 12-bit instruction width fit compact carrier-generation code with bit-banged PWM on any GPIO, and the static CMOS design means the part can wake on interrupt from sleep for long battery life. The SOIC-18 footprint is industry-standard for handheld devices, and the small 25-byte RAM holds the transmit state and key matrix without external memory.
Recommended
LED Driver and Signage Controller
In decorative LED strips, channel-letter signs and small DMX-style fixtures, the PIC16C54CT-04/SO drives WS2811 or constant-current LED driver chains via bit-banged serial protocols. Its 768 B program memory is sufficient for chase patterns, color fades, and address decoding, while the 12 GPIO pins either drive LED data lines or interface to external shift registers like 74HC595 for higher channel counts. The 3.0-5.5 V supply rails match standard LED driver IC inputs without extra level translation. For longer chains, the part's deterministic 4-cycle instruction timing makes software UART implementation straightforward.
Recommended
Industrial Timer and Sequencer
The PIC16C54CT-04/SO is well-suited to industrial timer, sequencer and relay-logic-replacement modules. Its 33-instruction RISC core executes deterministic timing loops, and the on-chip watchdog timer with internal RC oscillator prevents lockup in electrically noisy panels. The commercial temperature range (0C to +70C) covers most indoor cabinets, and the industrial variant PIC16C54CT-04I/SO extends this to -40C to +85C for outdoor enclosures. Pair the MCU with ULN2003A for relay drive and TVS diodes for transient protection on field wiring.
Recommended
Simple Sensor Hub with External ADC
The PIC16C54CT-04/SO can act as a low-cost sensor hub, polling one or two external analog sensors via an external ADC such as the MCP3002 over bit-banged SPI. The 12 GPIO pins interface to the ADC, the sensor enable line, and the UART or one-wire output to a host. The 768 B program memory and 25 B RAM hold the calibration table and read-and-forward logic. Compared to higher-pin-count PIC16F parts, the PIC16C54C-04/SO is the lowest-cost 18-pin SOIC MCU, making it the default for sub-$2 BOM nodes.
Recommended
Educational 8-bit MCU Trainer Board
The PIC16C54CT-04/SO is a classic teaching part for university and self-study 8-bit embedded courses, where students learn RISC pipelines, OTP programming, and minimal-resource firmware design. Its 33-instruction set and small 25-byte RAM force good code discipline, while the SOIC-18 package is easy to hand-solder or use on a breakout board. Microchip's PICkit programmers support the part via ICSP, and the same board design can be re-flashed by migrating to PIC16F54-I/SO (Flash) for class projects requiring code iteration.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C54CT-04/SO β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C54C-04/SO | PIC16C54A-04/SO | PIC16C54A-04/SS | PIC16C54C-04/P |
|---|---|---|---|---|---|
| Package | 18-SOIC | 18-SOIC - same | 18-SOIC - same | 20-SSOP - different footprint | 18-PDIP - through-hole, different footprint |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | OTP EPROM (768 B) | Flash (768 B) | OTP EPROM (768 B) | OTP EPROM (768 B) | Flash (768 B) |
| Maximum Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Data RAM | 25 B | 25 B | 25 B | 25 B | 25 B |
| I/O Pins | 12 | 12 | 12 | 12 | 12 |
| Supply Voltage | 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 |
| Lifecycle Status | NRND | NRND | Mature (last time buy) | Mature (last time buy) | NRND |
Key Differentiators
- Same SOIC-18 footprint as Flash sibling with no firmware changes (vs PIC16C54C-04/SO)
- Newer silicon revision C vs older A revision (vs PIC16C54A-04/SO)
- Lowest unit cost in the PIC16C5x family (vs PIC16C55 / PIC16C57 family)
Design Notes
Decouple VDD (pin 18) with a 100 nF ceramic capacitor placed within 5 mm of the pin, plus a bulk 10 uF electrolytic or tantalum on the same rail. The PIC16C5x family is sensitive to supply droop during Flash or EPROM programming; using a low-ESR cap reduces write errors. Tie VSS (pin 7) to a solid ground pour. Estimated: total quiescent current for the MCU alone is typically <2 mA at 4 MHz and 5 V, per the PIC16C5x datasheet DC characteristics.
Place the 4 MHz ceramic resonator (or crystal) close to OSC1 (pin 8) and OSC2 (pin 9) with short, symmetric traces. Keep the MCLR/VPP line short and isolated from switching nodes; add a 10 kohm pull-up to VDD and a 100 nF cap to ground on MCLR for clean power-on-reset behavior. The ICSP clock/data lines can be reused as GPIO after programming, but route them to a header with 4.7 kohm series resistors to protect against programmer shorts.
Do not exceed 5.5 V on VDD - the OTP cell write voltage is sensitive to overshoot. Always configure unused GPIO pins as outputs (not inputs) to avoid floating-pin current draw. The PIC16C54C has no on-chip UART, I2C, or ADC; bit-banged peripherals must respect the 4-cycle instruction timing or you will see baud-rate and timing drift. For new designs, prefer PIC16F54-I/SO (Flash, active) over PIC16C54CT-04/SO (NRND) unless OTP cost is essential.
Compliance Information
RoHS / REACH / lead-free status not explicitly stated in the verified web data; flagged as unknown. Microchip PIC16C5x parts generally comply with Microchip's standard environmental program; verify on the manufacturer's product page before committing to a RoHS-critical design.
