PIC16C54CT-04I/SO - 8-bit OTP MCU, 4MHz, 12 I/O, SOIC-18 | Microchip
MPN: PIC16C54CT-04I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.29 | $2.29 |
| 10 | $2.18 | $21.80 |
| 100 | $1.94 | $194.00 |
| 500 | $1.72 | $860.00 |
| 1,000 | $1.55 | $1,550.00 |
PIC16C54CT-04I/SO Overview
An 8-bit microcontroller (MCU) is a small computer-on-a-chip integrating a CPU, program memory, RAM, and peripherals on a single die. Within the broader hierarchy, an MCU belongs to the embedded processor family, sits below microprocessors (MPUs) in complexity, and forms the foundation of nearly every modern electronic product. The PIC16C5X sub-family, to which this part belongs, is Microchip's original baseline architecture using 12-bit-wide instructions that yield 2:1 code compression versus competing 8-bit MCUs, allowing the small 768-byte OTP to host meaningful control applications.
Key features include a RISC-like instruction set with only 33 single-word/single-cycle instructions, a programmable code-protection mechanism for the OTP array, a Watchdog Timer with on-chip RC oscillator for reliable operation without external components, and a Power-on Reset (POR) circuit. The part supports supply voltages of 3.0 V to 5.5 V (extended) per the PIC16C5X family specification, making it compatible with both 3.3 V and 5 V system rails.
The PIC16C54CT-04I/SO uses a Harvard architecture with separate program and data buses plus a 2-stage pipeline, enabling most instructions to execute in a single instruction cycle (250 ns at 4 MHz). The 04 speed suffix designates the 4 MHz clock variant; higher-speed (20 MHz, 40 MHz) members of the family share the same die and pinout for drop-in upgrade.
Typical applications include low-cost consumer appliances, automotive body controllers, HVAC damper/sensor interfaces, simple remote-control transmitters, and battery-powered sensor signal conditioners. The OTP memory suits high-volume production where firmware is finalized and field reprogramming is not required. The C temperature suffix in the part number designates the industrial -40C to +85C range.
When designing with this device, allocate the I/O budget carefully: 12 of 18 pins are usable GPIO after power, ground, oscillator, and reset pins are reserved. Because the program memory is OTP, any firmware bug requires physical device replacement; plan to use a windowed CERDIP variant (PIC16C54C/JW) for prototype/emulation, then move to the SOIC OTP version for production.
This page synthesizes distributor inventory, parametric drop-in alternatives within the PIC16C5X family, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC16C54CT-04I/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 PIC16C54CT-04I/SO (same form factor and footprint) — differing in Package, Program Memory Size, Program Memory Type, Watchdog Timer, Core.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C54C-04I/SO
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC16C54CT-04I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C54C-04/SO
✅ Drop-In✓ In Stock
$1.38 / Unit
View Datasheet →PIC16C54A-04I/SO
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC16C54C-04/P
✅ Drop-In✓ In Stock
$1.71 / Unit
View Datasheet →PIC16C54C-20I/SO
✅ Drop-In✓ In Stock
$1.15 / Unit
View Datasheet →PIC16C54CT-04I/SO Maximum Ratings & Electrical Characteristics
| Core | PIC16C5X 8-bit RISC |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 768 B (512 x 12) |
| RAM Size | 25 B (25 x 8) |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle Time | 1 us (4 MHz clock, 4:1 divider) |
| Number of I/O Pins | 12 |
| Data Bus Width | 8-bit |
| Supply Voltage Range | 3.0 V to 5.5 V |
| Operating Temperature Range | -40 C to +85 C (Industrial, 'I' suffix) |
| Package | 18-SOIC (0.295 inch, 7.50 mm width) |
| Mounting Type | Surface Mount |
| Instruction Set Width | 12-bit |
| Number of Instructions | 33 single-word instructions |
| Watchdog Timer | Yes (with on-chip RC oscillator) |
| Power-on Reset | Yes |
| Code Protection | Programmable via EPROM bit |
PIC16C54CT-04I/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 | RTCC — Real-Time Clock/Counter pin (also GPIO) |
| Pin 4 | MCLR — Master Clear reset (active low, internal pull-up) |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0 — Port B bit 0 (bidirectional I/O) |
| Pin 7 | RB1 — Port B bit 1 (bidirectional I/O) |
| Pin 8 | RB2 — Port B bit 2 (bidirectional I/O) |
| Pin 9 | RB3 — Port B bit 3 (bidirectional I/O) |
| Pin 10 | RB4 — Port B bit 4 (bidirectional I/O) |
| Pin 11 | RB5 — Port B bit 5 (bidirectional I/O) |
| Pin 12 | RB6 — Port B bit 6 (bidirectional I/O) |
| Pin 13 | RB7 — Port B bit 7 (bidirectional I/O) |
| Pin 14 | VDD — Positive supply (3.0 V to 5.5 V) |
| Pin 15 | OSC2 — Oscillator output (crystal or RC) |
| Pin 16 | OSC1 — Oscillator input (crystal or RC) |
| Pin 17 | RA0 — Port A bit 0 (bidirectional I/O) |
| Pin 18 | RA1 — Port A bit 1 (bidirectional I/O) |
Typical Applications
PIC16C54CT-04I/SO is suitable for 6 applications: Low-Cost Consumer Appliance Controller, Automotive Body Control Module (Legacy), HVAC Sensor Interface Module, Remote Control Transmitter, Battery-Powered Sensor Signal Conditioner, Industrial Indicator and Annunciator Panel.
Low-Cost Consumer Appliance Controller
The PIC16C54CT-04I/SO's 768 B OTP, 25 B RAM, and 12 GPIO provide just enough logic to drive a simple appliance controller (toaster, blender, rice cooker, or fan speed switch) where 4 MHz execution is sufficient for sequential state-machine code. Its industrial -40C to +85C range handles kitchen and laundry environments. The OTP suits high-volume production where firmware is locked and unit cost dominates. Place a 100 nF decoupling cap on VDD and a 10 kohm pull-up on MCLR; reserve 2 GPIO for relay or TRIAC drive, 4 for the user keypad, and 6 for LED indicators.
Recommended
Automotive Body Control Module (Legacy)
The PIC16C54CT-04I/SO is a legacy fit for automotive body-electronics sub-modules such as mirror controllers, seat-position switches, and lighting sequencers where 12 GPIO drive relays and switches directly. The industrial -40C to +85C range covers cabin environments. The 04 speed grade provides 250 ns instruction cycles, adequate for slow electromechanical actuators. Use the Watchdog Timer to recover from automotive load-dump transients; the on-chip RC oscillator keeps the MCU running even if the main crystal is disturbed by EMI. Plan for OTP programming during the manufacturing flow because field firmware updates are not possible.
Recommended
HVAC Sensor Interface Module
In HVAC damper and thermostat interfaces, the PIC16C54CT-04I/SO handles 1-2 analog sensors via an external ADC, drives a small LCD or LED matrix, and switches a relay to command the blower. With 12 GPIO, you can implement a basic 7-segment display plus 4 keypad buttons and 1 relay output. The 4 MHz instruction rate easily scans a keypad at 10 ms debounce intervals. Industrial temperature operation tolerates attic and basement installations. The OTP memory suits sealed units where firmware is locked at production. A PIC16C54C-04I/SO drop-in replacement is preferred for tube-based assembly.
Recommended
Remote Control Transmitter
The PIC16C54CT-04I/SO is well-suited to simple IR/RF remote control transmitters where 32-64 buttons are scanned through a matrix and a single GPIO drives the IR LED or SAW transmitter. The 12 GPIO and 768 B OTP accommodate a 4x8 button matrix with debouncing and a small lookup table. The 4 MHz clock allows IR carrier generation at 38 kHz with 50% duty cycle via software toggling. Industrial temperature range tolerates indoor and outdoor environments. The OTP keeps per-unit cost low for high-volume consumer remotes. Use the Watchdog Timer to recover from button-stuck events.
Recommended
Battery-Powered Sensor Signal Conditioner
In battery-powered sensor modules (temperature loggers, simple moisture meters, door/window sensors), the PIC16C54CT-04I/SO can wake periodically, read a sensor via ADC, and transmit or log the result. The 25 B RAM holds one or two sensor readings; the 768 B OTP accommodates a simple averaging filter. The PIC16C5X family's CMOS design supports sleep current in the microamp range. Industrial temperature operation handles outdoor or attic installations. OTP is acceptable since the sensor calibration data is fixed at production. A PIC16C54C-20I/SO swap increases throughput for higher-rate sampling.
Recommended
Industrial Indicator and Annunciator Panel
For industrial annunciator panels that light LEDs or drive small segmented displays based on 8-12 binary inputs, the PIC16C54CT-04I/SO fits comfortably. Its 12 GPIO map to 8 status inputs and 4 alarm outputs, with the Watchdog Timer ensuring recovery from transient faults. The industrial -40C to +85C range tolerates factory floor environments. 4 MHz execution scans inputs at sub-millisecond intervals. The OTP memory is appropriate for fixed-function panels. Use port B's internal weak pull-ups on input pins to save board space; bypass VDD with a 100 nF ceramic capacitor placed within 5 mm of the pin.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C54CT-04I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C54C-04I/SO | PIC16C54A-04I/SO | PIC16C54C-04/SO | PIC16C54C-20I/SO |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC | 18-SOIC (same) | 18-SOIC (same) | 18-SOIC (same) | 18-SOIC (same) |
| Maximum Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz |
| Program Memory | 768 B OTP | 768 B OTP | 768 B OTP | 768 B OTP | 768 B OTP |
| RAM Size | 25 B | 25 B | 25 B | 25 B | 25 B |
| GPIO Pins | 12 | 12 | 12 | 12 | 12 |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) |
| Supply Voltage Range | 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 |
Key Differentiators
- Tape-and-reel packaging for high-volume pick-and-place assembly (vs PIC16C54C-04I/SO)
- 4 MHz industrial-grade baseline MCU with PIC16C5X family pedigree (vs PIC16C54A-04I/SO)
- Industrial temperature range within the PIC16C5X SOIC family (vs PIC16C54C-04/SO)
Design Notes
Place a 100 nF ceramic decoupling capacitor within 5 mm of the VDD pin (pin 14) and a 10 uF bulk capacitor on the board power rail. The PIC16C5X family datasheet (DS30453D) recommends the 100 nF cap because supply transients couple directly into the internal logic and oscillator; the bulk capacitor stabilizes the rail under GPIO switching transients. For battery-powered designs, ensure the MCLR pull-up is at least 10 kohm to limit quiescent current, and consider using the Watchdog Timer's internal RC oscillator to keep the MCU in sleep most of the time.
Keep the OSC1/OSC2 traces short (under 10 mm) and isolated from switching signals. For a 4 MHz crystal, use a parallel resonant crystal with two 15-33 pF load capacitors per the PIC16C5X datasheet. Place the crystal and load capacitors as close to pins 15 and 16 as possible, with a ground guard ring around the oscillator area. Avoid routing digital signal traces under the crystal traces to minimize crosstalk into the oscillator.
The PIC16C54CT-04I/SO uses OTP memory, meaning the program cannot be erased or rewritten. Any firmware bug discovered after programming requires physical device replacement. For development, use the PIC16C54C/JW windowed CERDIP variant for UV-eraseable prototyping, then transition to the SOIC OTP part for production. Also note that the '04' suffix designates 4 MHz; do not attempt to drive this part above 4 MHz or timing errors will occur. The higher-speed PIC16C54C-20I/SO shares the same pinout for drop-in upgrade when faster execution is needed.
Port B on the PIC16C5X family has software-controllable internal weak pull-ups. Enable them via the OPTION register (bit 7 cleared) for inputs wired to switches or open-drain devices to eliminate external pull-up resistors. Port A has no internal pull-ups; external 10-100 kohm pull-ups are required for inputs. When driving LEDs or relays, use a current-limiting resistor or driver transistor; the PIC16C5X GPIO can sink or source about 25 mA per pin (100 mA total across all pins) per the DC characteristics table in DS30453D.
Compliance Information
RoHS, REACH, lead-free, and halogen-free statuses were not present in the verified web data; values are marked [DATA_NEEDED] in specs. AEC-Q100 not applicable: this part targets industrial/consumer markets, not automotive safety-critical.
