PIC16C54AT-20E/SO - 8-Bit 20MHz OTP MCU, 768B | Microchip
MPN: PIC16C54AT-20E/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.45 | $2.45 |
| 10 | $2.21 | $22.10 |
| 100 | $1.97 | $197.00 |
| 500 | $1.74 | $870.00 |
| 1,000 | $1.52 | $1,520.00 |
PIC16C54AT-20E/SO Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory, data RAM, and peripheral I/O on a single die. The PIC16C5x family is the foundational baseline PIC architecture, with subsequent generations adding more memory, peripherals, and flash memory. OTP microcontrollers sit in the broader hierarchy of microcontroller -> embedded controller -> semiconductor device; OTP variants are programmed once with custom firmware and cannot be erased, making them ideal for high-volume mature products where unit cost dominates.
Key features of the PIC16C54AT-20E/SO include a 12-bit instruction word, 33 single-word instruction set, 2-level hardware stack, 8-bit timer/counter (TMR0) with an 8-bit prescaler, and a watchdog timer (WDT) for reliable operation in industrial environments. The device operates from 4.5V to 5.5V and supports commercial temperature range. Power-on Reset (POR), Device Reset Timer (DRT), and an on-chip oscillator with selectable RC/HS/XT/LP modes reduce external component count.
Architecturally, the PIC16C5x uses a Harvard-style separate code/data path with a fixed 12-bit instruction width, enabling deterministic single-cycle instruction execution except for program branches. The "20" speed suffix denotes a 20 MHz oscillator / 5 MHz instruction cycle (4:1 clock-to-instruction divider), while "E" indicates the Extended temperature variant and "T" denotes Tape & Reel packaging.
Typical applications include simple logic replacement, low-cost consumer appliances, sensor conditioning front-ends, LED sequencing controllers, and battery chargers. The 18-SOIC package is a JEDEC-standard small-outline footprint, compatible with hand-soldering and standard SMT reflow lines.
When designing with this device, note that the PIC16C5x family does not support interrupts - all event handling is polled. Program memory is OTP, so firmware must be fully validated before programming. Use MPLAB X IDE with the MPASM assembler or XC8 compiler for firmware development.
This page synthesizes distributor pricing, drop-in alternative cross-references, and practical design notes not found in the standalone manufacturer datasheet.
Drop-in alternatives for PIC16C54AT-20E/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 PIC16C54AT-20E/SO (same form factor and footprint) — differing in Package, Program Memory Type, Core Architecture, Operating Temperature Range, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C54A-20/SO
✅ Drop-In✓ In Stock
$1.4 / Unit
View Datasheet →PIC16C54A-20I/SS
✅ Drop-In✓ In Stock
$2.51 / Unit
View Datasheet →PIC16C54A-20E/SS
✅ Drop-In✓ In Stock
$2.05 / Unit
View Datasheet →PIC16C54C-20E/SO
✅ Drop-In✓ In Stock
$1.12 / Unit
View Datasheet →PIC16F54-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C54AT-20E/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16C5x 8-bit RISC |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 768 B (512 x 12 words) |
| RAM Size | 25 B |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle | 200 ns (4:1 clock divider) |
| Instruction Set Size | 33 single-word instructions |
| I/O Pins | 12 |
| Timers | 1 x 8-bit (TMR0) with 8-bit prescaler |
| Watchdog Timer (WDT) | Yes (on-chip, software-enabled) |
| Hardware Stack | 2 levels |
| Supply Voltage | 4.5 V to 5.5 V |
| Operating Temperature Range | -40 C to +125 C (Extended, "E") |
| Package | 18-SOIC (0.295", 7.50 mm width) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant |
| Lead-Free / Halogen-Free | Lead-free per Microchip product page |
| Pin Count | 18 |
| On-Chip Oscillator Modes | RC, HS, XT, LP |
PIC16C54AT-20E/SO Pin Configuration
| Pin 1 | RA2 — Port A bit 2 (bidirectional digital I/O) |
| Pin 2 | RA3 — Port A bit 3 (bidirectional digital I/O) |
| Pin 3 | T0CKI/RA4 — Timer 0 external clock input / Port A bit 4 |
| Pin 4 | MCLR/VPP — Master Clear (active-low reset) / ICSP programming voltage |
| Pin 5 | VSS — Ground reference (0 V) |
| Pin 6 | RB0/INT — Port B bit 0 (external interrupt - note: PIC16C5x family does not support interrupts) |
| Pin 7 | RB1 — Port B bit 1 (bidirectional digital I/O) |
| Pin 8 | RB2 — Port B bit 2 (bidirectional digital I/O) |
| Pin 9 | RB3 — Port B bit 3 (bidirectional digital I/O) |
| Pin 10 | RB4 — Port B bit 4 (bidirectional digital I/O) |
| Pin 11 | RB5 — Port B bit 5 (bidirectional digital I/O) |
| Pin 12 | RB6 — Port B bit 6 (bidirectional digital I/O / ICSP clock) |
| Pin 13 | RB7 — Port B bit 7 (bidirectional digital I/O / ICSP data) |
| Pin 14 | VDD — Positive supply voltage (4.5 V to 5.5 V) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / clock output (Fosc/4) |
| Pin 16 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 17 | RA0 — Port A bit 0 (bidirectional digital I/O) |
| Pin 18 | RA1 — Port A bit 1 (bidirectional digital I/O) |
Typical Applications
PIC16C54AT-20E/SO is suitable for 6 applications: Logic Replacement with Embedded Control, Consumer Appliance Control (Microwave, Washing Machine, Fan), LED Sequencing and Lighting Controllers, Battery Charger State Machine Controllers, Sensor Conditioning and Alarm Front-Ends, Remote Control and IR Toy Transmitters.
Logic Replacement with Embedded Control
The PIC16C54AT-20E/SO is ideal for replacing discrete logic ICs (74-series gates) with a programmable microcontroller, saving PCB area while adding product differentiation. With 768 bytes of OTP for custom logic and 12 I/O pins, designers can implement state machines, timing chains, and combinational logic in firmware rather than discrete gates. The 20 MHz / 200 ns instruction cycle provides deterministic response times for real-time control. Power consumption is sub-10 mA active at 5V, and the 18-SOIC footprint drops directly onto a 7400-series pad layout with minor wiring adjustments.
Recommended
Consumer Appliance Control (Microwave, Washing Machine, Fan)
The PIC16C54AT-20E/SO fits low-to-mid-end consumer appliance controllers where the BOM cost dominates and firmware is fixed at production. Its 768-byte OTP stores pre-validated motor timing sequences, button debounce logic, and LED indicators; 25 bytes of RAM handles current state without external SRAM. The Extended -40C to +125C temperature range covers under-hood and inside-appliance environments. The 18-SOIC JEDEC footprint is compatible with high-volume SMT lines; programming is done at contract manufacturer before wave-solder attach.
Recommended
LED Sequencing and Lighting Controllers
The PIC16C54AT-20E/SO drives multi-channel LED chase, fade, and pattern controllers in decorative lighting, signage, and automotive interior strips. Its 12 I/O pins can directly drive 12 LEDs via current-limit resistors or interface to high-side LED drivers like the TLC59108; the TMR0 8-bit timer with prescaler generates millisecond-accurate PWM in firmware. The 20 MHz instruction rate supports smooth fading curves up to 256 brightness steps per channel. OTP memory ensures firmware immutability - critical for safety-certified lighting products.
Recommended
Battery Charger State Machine Controllers
Low-end lead-acid or NiMH battery chargers use the PIC16C54AT-20E/SO to implement charge-profile state machines (bulk / absorption / float) without the cost of a full analog controller. The 768-byte OTP stores voltage thresholds, timer durations, and fault-recovery logic; the 12 I/O pins monitor cell voltage via resistor dividers and drive relay / MOSFET gates. The 20 MHz cycle time supports rapid ADC-free comparator-based charge termination. Extended temperature range supports under-the-hood automotive and outdoor solar installations.
Recommended
Sensor Conditioning and Alarm Front-Ends
The PIC16C54AT-20E/SO acts as a low-cost sensor front-end in smoke detectors, water-leak sensors, and simple security alarms. It polls a thermistor / reed switch / PIR sensor, debounces the input via firmware, and drives a piezo buzzer or relay. With 25 bytes of RAM and the 2-level stack, the firmware implements latching alarm logic and self-test routines. The Extended temperature grade supports attic and outdoor installations; the OTP memory prevents accidental field re-programming of safety-critical firmware.
Recommended
Remote Control and IR Toy Transmitters
Low-cost IR remote controls and toy RC transmitters benefit from the PIC16C54AT-20E/SO's small footprint, low power, and deterministic timing. The 12 I/O drive an IR LED via a transistor, read a 4x4 button matrix, and generate 38 kHz carrier PWM in firmware at 20 MHz. The 768-byte OTP holds button-to-command lookup tables for TV/DVD/STB protocols. OTP prevents firmware copying in mass-market consumer products; the JEDEC 18-SOIC package is drop-in compatible with industry-standard remote-control PCBs.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C54AT-20E/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C54A-20/SO | PIC16C54A-20E/SS | PIC16C54C-20E/SO | PIC16F54-I/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 |
| Program Memory | 768 B OTP | 768 B OTP | 768 B OTP | 1024 B OTP | 768 B Flash |
| RAM Size | 25 B | 25 B | 25 B | 25 B | 25 B |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Memory Type | OTP | OTP | OTP | OTP | Flash |
| Operating Temperature | -40C to +125C (Extended) | 0C to +70C (Commercial) | -40C to +125C (Extended) | -40C to +125C (Extended) | -40C to +85C (Industrial) |
| I/O Pins | 12 | 12 | 12 | 12 | 12 |
| Instruction Set | 33 instructions, 12-bit | 33 instructions, 12-bit | 33 instructions, 12-bit | 33 instructions, 12-bit | 33 instructions, 12-bit |
Key Differentiators
- Extended temperature grade -40C to +125C in production SOIC (vs PIC16F54-I/SO)
- Same-die drop-in upgrade path to 1024-byte OTP (vs PIC16C54A-20E/SS)
- OTP immutability for safety-certified / regulated products (vs PIC16F54-I/SO)
Design Notes
The PIC16C54A uses One-Time-Programmable (OTP) memory. Verify ALL firmware logic on a Flash-equivalent (PIC16F54-I/SO or PIC16C54A-20E/P with emulator) BEFORE committing to OTP programming. A single firmware bug requires scrapping all programmed parts. Always use Microchip's MPLAB X simulator with the PIC16C54A device selection for full coverage of the 33-instruction set, TMR0 behavior, and the 2-level hardware stack. Also note the PIC16C5x family has NO interrupt controller - all event handling must be polled in firmware, which can trip up engineers migrating from PIC16F or PIC18F devices.
The 18-SOIC (0.295" body width) JEDEC package requires a standard 1.27 mm pitch land pattern. Place a 0.1 uF decoupling capacitor within 5 mm of the VDD pin (pin 14), with a short, wide trace to VSS (pin 5). Use a ground plane on the bottom layer to provide low-impedance return for the OSC1/OSC2 crystal traces (pins 15/16). For HS-mode crystals (>4 MHz), keep crystal traces short (<10 mm) and surround them with a ground guard ring to reduce EMI. The MCLR/VPP pin (pin 4) requires a 10 kohm pull-up to VDD for normal operation; during ICSP programming it sees 13V.
Estimated: at 20 MHz, 5V, and all 12 I/O pins switching at maximum capacitive load, the PIC16C54AT-20E/SO draws approximately 10-15 mA active. With the WDT disabled and TMR0 gated off in sleep, quiescent current drops below 4 uA in sleep mode - well-suited for battery-powered sensor applications. For designs that alternate active/sleep at >1000:1 duty cycles, size the decoupling capacitor at 1 uF (not 0.1 uF) to handle inrush during wake-up. The 4.5V minimum supply is required for HS-mode oscillator operation; HS mode at 20 MHz requires a 20 MHz fundamental-mode crystal with 15-33 pF load capacitors.
Compliance Information
RoHS-compliant and lead-free per Microchip product page (DigiKey listing and TrustCompo green-component listing). AEC-Q100 qualification is not applicable for baseline PIC16C5x - choose PIC16C54C automotive variants if needed. Halogen-free status was not explicitly stated in the verified data and is marked unknown.
