PIC16C54A-20E/SS - 8-Bit 20MHz OTP MCU 768B | Microchip
MPN: PIC16C54A-20E/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.2 | $3.20 |
| 10 | $2.88 | $28.80 |
| 100 | $2.56 | $256.00 |
| 500 | $2.3 | $1,150.00 |
| 1,000 | $2.05 | $2,050.00 |
PIC16C54A-20E/SS Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory, working RAM, and peripheral I/O on one die. 8-bit MCUs like the PIC16C5X sit at the entry level of the microcontroller taxonomy: 8-bit -> RISC microcontroller -> embedded controller -> semiconductor. They typically serve cost- and power-sensitive deterministic control tasks rather than compute-heavy or user-interface applications, and the PIC16C5X family in particular targets low-cost, high-volume appliance, automotive, and industrial control designs with a RISC architecture and Harvard bus structure.
Key differentiating features of the PIC16C54A-20E/SS include its OTP program memory (factory- or field-programmable but not electrically re-programmable in-circuit like flash), 12-bit wide instructions that yield roughly 2:1 code compression over competing 8-bit CISC cores, and a watchdog timer with its own on-chip RC oscillator for unattended operation. The wide operating temperature range suits automotive under-hood and industrial cabinet environments.
Architecturally, the PIC16C54A uses a two-stage pipelined Harvard architecture: the program and data buses are physically separate, so an instruction fetch does not collide with a data read. The 12-bit instruction word keeps opcode decoding logic small, which is why the silicon area (and cost) stays low even at 20 MHz throughput.
Typical applications include automotive body and chassis subsystems (window lifters, seat controllers, simple sensor interfaces), white goods and small appliance control (coffee makers, microwave ovens, washing machine user-interface panels), industrial control (sensor signal conditioning, relay drivers, simple PID loops implemented in firmware), and consumer electronics (remote controls, toys, low-cost key fobs).
When designing with this device, plan firmware layout around the OTP constraint: any firmware revision that needs to change program memory requires a new part. Designers targeting in-circuit reprogrammability should evaluate the pin-compatible PIC16F54 instead, which uses Flash program memory.
This page synthesizes distributor pricing, cross-reference alternatives, and practical design notes not found in the manufacturer datasheet alone, and is optimized for engineers and procurement teams evaluating PIC16C54A-20E/SS for new designs and legacy replacements.
Drop-in alternatives for PIC16C54A-20E/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 PIC16C54A-20E/SS (same form factor and footprint) — differing in Package, Core Architecture, Program Memory Size, Program Memory Type, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C54A-20E/SS
✅ Drop-In✓ In Stock
$2.05 / Unit
View Datasheet →PIC16C54A-20I/SS
✅ Drop-In✓ In Stock
$2.51 / Unit
View Datasheet →PIC16C54A-20/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C54A-04/SS
✅ Drop-In✓ In Stock
$1.18 / Unit
View Datasheet →PIC16C54A-04E/SS
✅ Drop-In✓ In Stock
$1.32 / Unit
View Datasheet →PIC16F54-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C54A-20E/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit RISC, Harvard bus |
| Instruction Set Width | 12 bits |
| Number of Instructions | 33 single-word |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns (single-cycle) |
| Branch Instruction Cycle | 400 ns (two-cycle) |
| Program Memory Type | OTP EPROM (One-Time-Programmable) |
| Program Memory Size | 768 B (512 x 12 words) |
| Data RAM | 25 bytes |
| General-Purpose I/O Pins | 12 |
| Operating Voltage Range | 4.5 V to 5.5 V |
| Operating Temperature Range | -40 °C to +125 °C (Extended) |
| Package | 20-SSOP (0.209 in / 5.30 mm body width) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited floor life at <30 °C / 85 % RH) |
| RoHS Status | Compliant |
| Lead-Free / Halogen-Free | Lead-free finish; matte-tin plating |
PIC16C54A-20E/SS Pin Configuration
| Pin 1 | RA2 — Port A bit 2 (bidirectional I/O) |
| Pin 2 | RA3 — Port A bit 3 (bidirectional I/O) |
| Pin 3 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Pin 4 | MCLR — Master Clear reset input (active low) |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — Port B bit 0 / external interrupt input |
| 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 (4.5 V to 5.5 V) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / clock-out |
| Pin 16 | OSC1/CLKIN — Oscillator input / external clock in |
| Pin 17 | RA0 — Port A bit 0 (bidirectional I/O) |
| Pin 18 | RA1 — Port A bit 1 (bidirectional I/O) |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C54A-20E/SS is suitable for 6 applications: Automotive Body and Chassis Control, White Goods and Small Appliance Control, Industrial Sensor Interface Modules, Remote Controls and Consumer Electronics, Simple LED Lighting Controllers, Battery Chargers and Power Management Front-Ends.
Automotive Body and Chassis Control
The PIC16C54A-20E/SS is well suited to automotive body and chassis subsystems that demand a wide temperature envelope and deterministic real-time response. Its extended -40 °C to +125 °C operating range covers under-hood and cabin environments, while the 200 ns single-cycle instruction execution supports time-critical tasks such as debouncing switch inputs, sequencing relay drivers, and polling simple sensor buses. The 12 GPIO pins are sufficient for window lifters, seat position controllers, mirror fold modules, and lighting timers, and the on-chip watchdog timer with its dedicated RC oscillator recovers the MCU from firmware lockups without external components. The 4.5 V to 5.5 V supply range aligns with the nominal 5 V rails common in legacy automotive ECUs. Compared with switching to a more modern ARM-core MCU, the PIC16C54A-20E/SS keeps BOM cost low and PCB footprint minimal at 20 pins in SSOP.
Recommended
White Goods and Small Appliance Control
Small domestic appliances such as coffee makers, microwave ovens, washing machine user-interface panels, and rice cookers benefit from the PIC16C54A-20E/SS's low unit cost, small 20-pin SSOP footprint, and 33-instruction RISC core that compiles to dense 12-bit instruction words. The 768-byte OTP program memory is well matched to fixed-function firmware that does not require field updates, and the 25-byte RAM is sufficient for state machines governing key-press scanning, seven-segment or simple LCD multiplexing, and triac-based heater or motor phase-angle control. The 4.5 V to 5.5 V supply range accepts the unregulated rails common in appliances after rectification and bulk filtering, while the on-chip watchdog timer guards against mains-borne brownouts and ESD events. Designers gain a fully static CMOS design that consumes essentially zero current in HALT mode.
Recommended
Industrial Sensor Interface Modules
The PIC16C54A-20E/SS serves as a low-cost front-end processor in industrial sensor interface modules that digitize analog signals, perform linearization, and present a digital output to a higher-level controller. Its 20 MHz throughput supports polling multiple sensor channels at modest sample rates, and the 12 GPIO pins can be allocated to multiplexed ADC channel selection, opto-isolated digital inputs, and relay or MOSFET driver outputs. The extended -40 °C to +125 °C temperature grade matches unconditioned industrial cabinets and proximity to motor drives, and the OTP program memory prevents accidental firmware corruption in the field. The Harvard bus architecture and deterministic instruction timing simplify IEC 61508 SIL-1 and similar functional-safety analyses for non-critical control loops.
Recommended
Remote Controls and Consumer Electronics
Infrared remote controls, RF key fobs, simple toys, and other consumer devices leverage the PIC16C54A-20E/SS's combination of low cost, small package, and adequate GPIO for button matrices, IR or sub-GHz RF transmitters, and LED indicators. The 200 ns instruction cycle is more than sufficient to bit-bang standard RC5, NEC, or proprietary IR protocols at 38 kHz carrier, while the 768-byte OTP memory comfortably stores encoding tables, button de-bounce state machines, and battery-low detection routines. Low-power HALT mode keeps standby current in the microamp range for hand-held battery-powered applications. The 5 V supply range accepts two alkaline or three NiMH cells, simplifying power-tree design and reducing BOM cost.
Recommended
Simple LED Lighting Controllers
LED lighting controllers for architectural strips, signage, decorative fixtures, and accent lighting often need only modest processing capability to run PWM dimming, color-mixing, and pattern sequencing algorithms. The PIC16C54A-20E/SS delivers 12 GPIO pins that can directly drive low-side MOSFET gates via PWM, or feed external constant-current LED drivers with logic-level enable and dim signals. The 20 MHz clock supports multiple PWM channels at frequencies above the audible band to avoid magnetostrictive whine in inductors, and the OTP memory holds a single fixed lighting scene or pattern. The extended -40 °C to +125 °C temperature grade enables deployment in enclosed luminaires where ambient temperatures rise significantly.
Recommended
Battery Chargers and Power Management Front-Ends
Low-power battery chargers for two-cell packs, solar garden lights, and standby UPS systems can use the PIC16C54A-20E/SS as the supervisory controller for voltage and current sensing, charge-state sequencing, and fault logging. The 20 MHz throughput is ample for closed-loop PWM regulation, and the 12 GPIO ports support analog multiplexer channels, status LEDs, and a low-side MOSFET gate driver. The 4.5 V to 5.5 V supply range is compatible with a small linear regulator fed from a higher battery rail, and the on-chip watchdog timer with its own RC oscillator is critical in unattended systems where firmware lock-up could lead to overcharge conditions. The OTP memory prevents inadvertent field reprogramming that could compromise safety.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C54A-20E/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C54A-20I/SS | PIC16C54A-20/SS | PIC16C54A-04/SS | PIC16C54A-04E/SS | PIC16F54-I/SS |
|---|---|---|---|---|---|---|
| Package | 20-SSOP (5.30 mm) | 20-SSOP - same | 20-SSOP - same | 20-SSOP - same | 20-SSOP - same | 20-SSOP - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash (reprogrammable) |
| Program Memory Size | 768 B (512 x 12) | 768 B (512 x 12) | 768 B (512 x 12) | 768 B (512 x 12) | 768 B (512 x 12) | 768 B (512 x 12) |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 4 MHz | 4 MHz | 20 MHz |
| Temperature Grade | Extended -40 to +125 C | Industrial -40 to +85 C | Commercial 0 to +70 C | Commercial 0 to +70 C | Extended -40 to +125 C | Industrial -40 to +85 C |
| Data RAM | 25 bytes | 25 bytes | 25 bytes | 25 bytes | 25 bytes | 25 bytes |
| GPIO Count | 12 | 12 | 12 | 12 | 12 | 12 |
| Operating Voltage Range | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 2.0 V to 5.5 V (Flash variant) |
Key Differentiators
- Widest temperature range in the PIC16C54A SSOP family (vs PIC16C54A-20/SS)
- Recommended replacement path with in-circuit reprogrammability (vs PIC16F54-I/SS)
- Four times the throughput of the lower-cost speed grade (vs PIC16C54A-04/SS)
Design Notes
The PIC16C54A-20E/SS requires a stable 4.5 V to 5.5 V supply; bulk-decouple VDD with at least a 10 µF aluminum or tantalum capacitor close to the IC pins, and add a 0.1 µF ceramic bypass to suppress switching noise from external loads. The MCLR pin must be held above Vih (0.85 VDD) for normal operation; tie it to VDD through a 10 kΩ pull-up and place a 0.1 µF capacitor on MCLR to filter ESD and EFT events typical in automotive and industrial environments.
OTP program memory can be written exactly once per address; any firmware revision that requires a code change needs a new physical part. If your design tolerates field firmware updates, choose the pin-compatible PIC16F54-I/SS instead, which uses Flash and is electrically reprogrammable in-circuit. Programming the PIC16C54A-20E/SS requires a high-voltage (about 13 V) VPP pulse on the MCLR pin during ICSP, exceeding the normal VDD, so the MCLR pull-up network must allow this programming voltage without damage to surrounding components.
Keep the OSC1/OSC2 traces short and symmetric to avoid parasitic capacitance that can pull the oscillator off frequency; place the crystal or resonator within 5 mm of the pins. For RC-oscillator configurations, route the resistor and capacitor as close to OSC1 as possible, with the OSC2 pin left open. Use a ground pour under the MCU and stitch vias around the perimeter of the SSOP package to provide a low-impedance thermal and return path; although the PIC16C54A-20E/SS consumes little power, the ground pour also reduces radiated EMI from the GPIO drivers.
Compliance Information
RoHS-compliant per Microchip product page; lead-free matte-tin finish. Not AEC-Q100 qualified - automotive designs should verify EMC and environmental compliance at the system level. Halogen-free status not explicitly stated in the verified web data and is therefore marked unknown.
