PIC16C54-HSE/SS - 8-Bit EPROM MCU 20MHz 768B OTP 20-SSOP | Microchip
MPN: PIC16C54-HSE/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.95 | $2.95 |
| 10 | $2.65 | $26.50 |
| 100 | $2.3 | $230.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.85 | $1,850.00 |
PIC16C54-HSE/SS Overview
What is an 8-bit OTP microcontroller? An 8-bit OTP microcontroller is a small, low-cost, fully-static computing device that integrates a CPU, program memory, RAM, and peripheral I/O on a single CMOS die. The EPROM-based OTP memory is written once using a device programmer and cannot be erased, which makes these parts economical for high-volume embedded products where code is fixed at production time. PIC16C5X MCUs occupy the entry-level tier of the 8-bit microcontroller taxonomy: microcontroller -> 8-bit MCU -> PIC family -> PIC16C5X sub-family -> CMOS RISC core with 12-bit instruction set.
Key features of the PIC16C54-HSE/SS include 25 bytes of general-purpose RAM, 12 digital I/O pins arranged as three ports (PORT A, PORT B, PORT C), an 8-bit timer/counter (TMR0) with an 8-bit prescaler, a watchdog timer with its own on-chip RC oscillator, power-on reset, and a power-saving SLEEP mode. The HSE suffix designates a 20 MHz high-speed oscillator variant within the PIC16C54 range, and the SS suffix denotes the SSOP-20 industrial/commercial package.
Architecturally, the PIC16C5X family uses a Harvard architecture with separate program and data buses, a 2-stage pipeline, and a RISC instruction set that executes most instructions in a single instruction cycle (4 oscillator clocks). This pipeline, combined with the static CMOS design, gives a deterministic 200 ns instruction cycle at 20 MHz. Code density is roughly 2:1 better than competing 8-bit CISC architectures because the 12-bit fixed instruction width matches the register file granularity.
Typical applications include low-cost consumer appliances, automotive sub-system controllers, battery chargers, simple sensor interfaces, remote controls, LED drivers, and small industrial controllers. Because the program memory is OTP, the part is best suited to designs whose firmware is frozen at production and does not require field updates. Compared with the FLASH-based PIC16F54 successor, the PIC16C54-HSE/SS trades reprogrammability for lower unit cost in mature, stable designs.
When designing with this device, note that in-circuit serial programming (ICSP) is not available on the OTP PIC16C5X family - code must be loaded by a parallel programmer such as the Microchip MPLAB PM3 before the part is soldered. Decoupling capacitors of 0.1 uF should be placed close to VDD and VSS, and unused I/O pins should be configured as outputs to minimize current draw in SLEEP mode. The 25-byte RAM budget means that deeply nested call stacks or large lookup tables must be kept in program memory.
This page synthesizes distributor pricing, drop-in same-package alternatives drawn from the Microchip PIC16C5X family, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16C54-HSE/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 PIC16C54-HSE/SS (same form factor and footprint) — differing in Core Architecture, Operating Temperature, Package, Timers, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C54C-20I/SS
✅ Drop-In✓ In Stock
$1.74 / Unit
View Datasheet →PIC16C54A-20I/SS
✅ Drop-In✓ In Stock
$2.51 / Unit
View Datasheet →PIC16C54CT-20E/SS
✅ Drop-In✓ In Stock
$1.89 / Unit
View Datasheet →PIC16F54-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C54-HSE/SS Maximum Ratings & Electrical Characteristics
| Product Family | PIC16C5X (PIC16C54 sub-family) |
| Core Architecture | 8-bit RISC, Harvard, 2-stage pipeline |
| Instruction Set Width | 12 bits, 33 single-word instructions |
| Instruction Cycle Time | 200 ns at 20 MHz (4 Tcy per instruction) |
| Program Memory (ROM/EPROM) | 768 bytes (512 x 12), OTP EPROM |
| Data RAM | 25 bytes general purpose |
| I/O Pins | 12 digital bidirectional |
| Timers | TMR0 8-bit with 8-bit prescaler |
| Watchdog Timer | Yes, with dedicated on-chip RC oscillator |
| Maximum Clock Speed | 20 MHz (HSE suffix) |
| Supply Voltage (VDD) | 4.5 V to 5.5 V |
| Operating Temperature | 0 C to +70 C (commercial) |
| Package | 20-pin SSOP (5.30 mm body width) |
| Mounting Type | Surface Mount |
| ICSP / In-Circuit Programming | Not supported on PIC16C5X OTP family |
| Power-on Reset | Yes |
| SLEEP / Power-Save Mode | Yes |
PIC16C54-HSE/SS Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O, PORTA bit 2 |
| Pin 2 | RA3 — Bidirectional I/O, PORTA bit 3 |
| Pin 3 | RTCC — TMR0 real-time clock/counter external input |
| Pin 4 | MCLR — Master clear reset input, active low |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0 — Bidirectional I/O, PORTB bit 0 |
| Pin 7 | RB1 — Bidirectional I/O, PORTB bit 1 |
| Pin 8 | RB2 — Bidirectional I/O, PORTB bit 2 |
| Pin 9 | RB3 — Bidirectional I/O, PORTB bit 3 |
| Pin 10 | RB4 — Bidirectional I/O, PORTB bit 4 |
| Pin 11 | RB5 — Bidirectional I/O, PORTB bit 5 |
| Pin 12 | RB6 — Bidirectional I/O, PORTB bit 6 |
| Pin 13 | RB7 — Bidirectional I/O, PORTB bit 7 |
| Pin 14 | VSS — Ground reference |
| Pin 15 | OSC2 — Oscillator output, crystal/ceramic resonator connection |
| Pin 16 | OSC1 — Oscillator input, crystal/ceramic/resistor connection |
| Pin 17 | VDD — Positive supply voltage, 4.5 V to 5.5 V |
| Pin 18 | RC2 — Bidirectional I/O, PORTC bit 2 |
| Pin 19 | RC1 — Bidirectional I/O, PORTC bit 1 |
| Pin 20 | RC0 — Bidirectional I/O, PORTC bit 0 |
Typical Applications
PIC16C54-HSE/SS is suitable for 6 applications: Low-Cost Consumer Appliance Controllers, Battery Charger and Power Management Front-Ends, Automotive Sub-System Controllers (Body Electronics), IR Remote Controls and Wireless Transmitters, Industrial Sensor Interfaces and Front-End Logic, LED Display and Signage Drivers.
Low-Cost Consumer Appliance Controllers
The PIC16C54-HSE/SS suits high-volume consumer appliances such as toaster ovens, coffee makers, and simple washing-machine sub-modules where the BOM cost is dominated by the microcontroller. Its 20 MHz 8-bit RISC core, 768 bytes of OTP EPROM, and 12 I/O pins cover timing loops, relay drivers, and 7-segment LED multiplexing with no external peripherals required. The SSOP-20 footprint fits within the compact appliance PCBs while leaving enough pins for keypad scanning and triac firing. Designers should allocate code space conservatively because the OTP memory cannot be updated after production - firmware bugs require a part re-spin.
Recommended
Battery Charger and Power Management Front-Ends
The PIC16C54-HSE/SS can run the charging state machine for lead-acid, NiCd, or simple lithium battery packs, where its 8-bit TMR0 with prescaler provides the timing resolution needed for CC-CV transitions and termination detection. The 20 MHz clock delivers a 200 ns instruction cycle that is fast enough to monitor current-sense ADCs through the I/O pins and switch MOSFETs with minimal propagation delay. OTP EPROM is acceptable because charger firmware rarely changes, and the SSOP-20 package eases thermal management inside the charger enclosure. Pair the MCU with an external op-amp current-sense amplifier and a comparator for hardware-level safety redundancy.
Recommended
Automotive Sub-System Controllers (Body Electronics)
Inside the automotive body-electronics domain, the PIC16C54-HSE/SS can drive window lifters, mirror adjusters, or simple lighting controllers where 12 digital I/O lines and 768 bytes of OTP code are sufficient. The HSE 20 MHz grade gives fast I/O response for safety-critical timing such as wiper control or seat-motor soft start. For under-hood applications that exceed the 70 C commercial limit, designers should choose the PIC16C54C-20I/SS industrial variant in the same SSOP-20 package. The OTP architecture locks the firmware against unauthorized reflashing in the field, which is helpful for OEM IP protection.
Recommended
IR Remote Controls and Wireless Transmitters
Infrared remote-control transmitters for TVs, set-top boxes, and ceiling fans use the PIC16C54-HSE/SS to scan matrix keypads, encode RC-5 or NEC protocols, and modulate an IR LED through one of the 12 I/O pins. The SLEEP mode with watchdog wake-up allows multi-year battery life because the device consumes only a few microamps between key presses. The 768-byte OTP EPROM easily accommodates fixed protocol code, and the 20 MHz clock generates accurate 38 kHz or 40 kHz carrier frequencies without an external resonator. Production cost is minimized because no external memory or crystal is needed beyond a low-cost resonator.
Recommended
Industrial Sensor Interfaces and Front-End Logic
The PIC16C54-HSE/SS can sit at the front of an industrial sensor chain, debouncing mechanical switches, decoding quadrature encoders, or driving 4-20 mA current loops through PWM-and-op-amp signal conditioning. Its 20 MHz execution rate is enough to oversample simple sigma-delta bit streams on a single I/O pin, replacing a dedicated counter IC. The SSOP-20 industrial-grade variants such as PIC16C54C-20I/SS handle -40 C to +85 C factory-floor temperatures, while the OTP EPROM protects proprietary calibration coefficients from field tampering. Watchdog timer with its own RC oscillator gives autonomous recovery from brown-out events without external supervisor ICs.
Recommended
LED Display and Signage Drivers
Small to medium LED matrix signs and 7-segment display boards use the PIC16C54-HSE/SS to multiplex rows and columns, generate brightness modulation through software PWM, and accept UART or SPI commands from a host controller. With 12 I/O pins the MCU can directly drive up to an 8 x 4 LED matrix through low-side transistors, while the 20 MHz instruction rate keeps the refresh above 100 Hz to eliminate flicker. OTP EPROM is appropriate because the display patterns are fixed at the factory, and the SSOP-20 small outline helps fit the controller on crowded back-plane PCBs. For variable-message signs that need runtime updates, the FLASH-based PIC16F54-I/SS offers a smoother migration path.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C54-HSE/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C54C-20I/SS | PIC16C54A-20I/SS | PIC16C54CT-20E/SS | PIC16F54-I/SS |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 20-SSOP | 20-SSOP - same | 20-SSOP - same | 20-SSOP - same | 20-SSOP - same |
| Program Memory Type | OTP EPROM 768 B | OTP EPROM 768 B | OTP EPROM 768 B | OTP EPROM 768 B | FLASH 768 B (reprogrammable) |
| Max Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage (VDD) | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 2.5 V to 6.0 V (wider) | 4.5 V to 5.5 V | 2.0 V to 5.5 V (wider) |
| Operating Temperature | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +125 C (extended) | -40 C to +85 C (industrial) |
| Data RAM | 25 B | 25 B | 25 B | 25 B | 25 B |
| ICSP / Field Reprogramming | No (parallel programmer only) | No (parallel programmer only) | No (parallel programmer only) | No (parallel programmer only) | Yes (FLASH + ICSP) |
Key Differentiators
- Original PIC16C54 HSE silicon with 20 MHz speed grade (vs PIC16C54C-20I/SS)
- High-speed 20 MHz instruction throughput in commercial temperature range (vs PIC16C54A-20I/SS)
- Drop-in SSOP-20 footprint with full PIC16C5X 12-bit instruction set compatibility (vs PIC16F54-I/SS)
Design Notes
Place a 0.1 uF decoupling capacitor within 5 mm of the VDD pin (pin 17) and a bulk 10 uF capacitor near the SSOP-20 package to suppress switching noise. Keep the OSC1/OSC2 traces short and surrounded by a ground guard ring; the 20 MHz HSE grade is sensitive to capacitive loading that detunes the resonator. Use a 4-layer PCB with a continuous ground plane under the SSOP-20 footprint for best EMI performance; if a 2-layer board is unavoidable, stitch the ground plane with vias around the oscillator traces.
Do not assume ICSP is available on PIC16C54-HSE/SS designs - the PIC16C5X OTP family lacks the ICSP interface and must be programmed with a parallel programmer such as the MPLAB PM3 before the part is soldered onto the PCB. Ensure that unused I/O pins are configured as outputs (not inputs) to prevent floating-pin current draw in SLEEP mode. The MCLR pin requires a 10 kohm pull-up to VDD; do not leave it floating or the device will randomly reset. Finally, the 25-byte RAM budget means that recursive functions and large local arrays must be avoided - prefer program-memory lookup tables with RETLW instructions.
Estimated: At 20 MHz clock, 5.0 V VDD, and all 12 I/O pins switching at 50% duty, the PIC16C54-HSE/SS draws roughly 5 mA from VDD, dissipating 25 mW. The SSOP-20 package has a typical theta_JA of 120 C/W on a 2-layer board, giving a junction temperature rise of 3 C above ambient. At the commercial 70 C maximum this leaves substantial thermal headroom, but industrial 85 C designs should still verify with a thermal probe because ambient inside an enclosure can exceed the specification. For high-vibration automotive modules, add a conformal coating to protect the SSOP leads.
Compliance Information
RoHS and lead-free status were not stated in the Verified Web Data snippets; check the Microchip product page and the device marking for the definitive compliance codes. The PIC16C54-HSE/SS is a legacy OTP EPROM part that is not AEC-Q100 qualified for automotive safety applications - choose PIC16C54C-20I/SS or a PIC16F automotive-grade MCU for AEC-Q100 designs.