PIC16C54T-HSE/SS - 8-Bit OTP MCU, 20MHz, 768B EPROM | Microchip
MPN: PIC16C54T-HSE/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.62 | $16.20 |
| 100 | $1.38 | $138.00 |
| 500 | $1.2 | $600.00 |
| 1,000 | $1.05 | $1,050.00 |
PIC16C54T-HSE/SS Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, memory (program + RAM), and peripherals on one die. Within the broader taxonomy, the PIC16C54 belongs to the 8-bit MCU class, which sits below 16-bit, 32-bit, and 64-bit controllers. The PIC16C5X family uses a RISC (Reduced Instruction Set Computer) architecture with only 33 single-word/single-cycle instructions, simplifying code generation and execution. Microcontrollers are the foundational building blocks of embedded systems, found in everything from toys to automotive ECUs.
Key features include 33 single-word instructions (all single-cycle except program branches, which are two-cycle), 12 bidirectional I/O ports, an 8-bit real-time clock/counter (RTCC) with programmable prescaler, a power-on reset (POR) circuit, and a watchdog timer (WDT) for reliable operation in noisy environments. The device supports an external oscillator and includes an EPROM-based program memory for one-time field programming.
The PIC16C54 uses a Harvard architecture with separate program and data buses, allowing instruction fetch and operand access to occur in the same cycle. Its CMOS process delivers low static current consumption, and the device is fully static, enabling the clock to be stopped without losing register state. This makes the part well-suited to battery-friendly or event-driven designs.
Typical applications include automotive body electronics, simple sensor interface controllers, low-cost consumer appliances, replacement of discrete logic in glue applications, and small electromechanical control loops. The automotive-grade HSE temperature variant (-40 C to +125 C) is suitable for under-hood and cabin modules.
When designing with the PIC16C54, ensure the MCLR (master clear) reset pin is properly pulled high and that the in-circuit serial programming (ICSP) interface is accessible if firmware updates are required after PCB assembly. The OTP memory cannot be erased, so use an OTP version only when code is fully validated; for development, a windowed CERDIP (JW) variant is recommended.
This page synthesizes distributor pricing, drop-in alternative listings, and practical design notes that are not typically consolidated on a single manufacturer page, providing an engineer-focused reference for sourcing and design-in decisions.
Drop-in alternatives for PIC16C54T-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 PIC16C54T-HSE/SS (same form factor and footprint) — differing in Package, Program Memory Type, Program Memory Size, Core Architecture, Instruction Cycle Time.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C54CT-20E/SS
✅ Drop-In✓ In Stock
$1.89 / Unit
View Datasheet →PIC16C54C-20E/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C54A-20E/SS
✅ Drop-In✓ In Stock
$2.05 / Unit
View Datasheet →PIC16C54C-20I/SS
✅ Drop-In✓ In Stock
$1.74 / Unit
View Datasheet →PIC16C54AT-20E/SO
✅ Drop-In✓ In Stock
$1.52 / Unit
View Datasheet →PIC16C54T-HSE/SS Maximum Ratings & Electrical Characteristics
| Core | 8-bit PIC RISC |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 768 bytes (512 x 12-bit words) |
| RAM Size | 25 bytes |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns |
| Number of I/O Pins | 12 |
| Number of Instructions | 33 |
| Instruction Width | 12 bits |
| Supply Voltage | 4.5 V to 5.5 V |
| Operating Temperature Range | -40 C to +125 C (Automotive grade) |
| Timers | 1 x 8-bit RTCC with prescaler |
| Watchdog Timer | Yes |
| Package | 20-pin SSOP |
| Mounting Type | Surface Mount (Tape and Reel) |
| Architecture | Harvard, fully static CMOS |
| RoHS Status | Compliant |
PIC16C54T-HSE/SS Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O pin, Port A bit 2 |
| Pin 2 | RA3 — Bidirectional I/O pin, Port A bit 3 |
| Pin 3 | RTCC — Real-time clock/counter input (T0CKI) |
| Pin 4 | MCLR — Master clear reset input (active low) |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0 — Bidirectional I/O pin, Port B bit 0 |
| Pin 7 | RB1 — Bidirectional I/O pin, Port B bit 1 |
| Pin 8 | RB2 — Bidirectional I/O pin, Port B bit 2 |
| Pin 9 | RB3 — Bidirectional I/O pin, Port B bit 3 |
| Pin 10 | RB4 — Bidirectional I/O pin, Port B bit 4 |
| Pin 11 | RB5 — Bidirectional I/O pin, Port B bit 5 |
| Pin 12 | RB6 — Bidirectional I/O pin, Port B bit 6 |
| Pin 13 | RB7 — Bidirectional I/O pin, Port B bit 7 |
| Pin 14 | VSS — Ground reference (secondary) |
| Pin 15 | OSC2 — Oscillator output (crystal/ceramic resonator) |
| Pin 16 | OSC1 — Oscillator input (crystal/ceramic resonator) |
| Pin 17 | VDD — Positive supply voltage (4.5 V to 5.5 V) |
| Pin 18 | RA0 — Bidirectional I/O pin, Port A bit 0 |
| Pin 19 | RA1 — Bidirectional I/O pin, Port A bit 1 |
| Pin 20 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C54T-HSE/SS is suitable for 6 applications: Automotive Body Electronics, Low-Cost Consumer Appliance Control, Discrete Logic Replacement (Glue Logic MCU), Sensor Interface and Signal Conditioning, Battery-Friendly Event-Driven Devices, Educational and Hobbyist Embedded Projects.
Automotive Body Electronics
The PIC16C54T-HSE/SS suits automotive body modules such as seat controllers, mirror adjusters, simple lighting drivers, and HVAC damper actuators. Its HSE temperature grade (-40 C to +125 C) and 20 MHz instruction rate let it sample switches, debounce inputs, and drive relays or low-side FETs within tight timing margins. The 12 I/O pins are sufficient for 4-8 input switches plus 4-8 output drivers, while the 25-byte RAM and 768-byte OTP EPROM hold the simple state machine or lookup-table logic typical of body modules. The wide 4.5-5.5 V supply tolerates automotive cranking transients when paired with a TVS clamp, and the built-in watchdog timer catches firmware lockups on noisy LIN/CAN bus-adjacent boards. The SSOP-20 footprint is small enough for behind-panel PCB integration.
Recommended
Low-Cost Consumer Appliance Control
The PIC16C54T-HSE/SS is widely used in low-cost consumer appliances such as coffee makers, toaster ovens, hair dryers, and small kitchen blenders. The 33-instruction RISC core lets engineers develop simple state machines in assembly, fitting 768 bytes of program memory easily. The 12 I/O pins support up to 8 tactile switch inputs plus 4 triac or relay outputs, with the 8-bit RTCC timer handling keypad scanning or pulse-width modulation. The OTP EPROM is ideal for high-volume, cost-sensitive appliances where the code is finalized before tooling. The SSOP-20 package and tape-and-reel packaging suit high-speed SMT assembly lines, and the automotive-grade HSE temp range tolerates the elevated temperatures of enclosed appliance cabinets.
Recommended
Discrete Logic Replacement (Glue Logic MCU)
The PIC16C54T-HSE/SS excels as a programmable replacement for 74HC-series discrete logic gates, latches, and shift registers. Rather than wire-ORing multiple small-logic ICs on a board, a single PIC16C54 can implement custom decoding, sequencing, or pulse generation in firmware, reducing PCB area and BOM cost. The 20 MHz clock and 200 ns instruction cycle let it emulate logic at frequencies well above typical control-rate applications. The 25-byte RAM accommodates small lookup tables, and the 12 I/O pins can each be software-configured as input or output. OTP EPROM is appropriate for glue logic since the code rarely changes after the host product is released. This is a classic use case for the PIC16C5X family.
Recommended
Sensor Interface and Signal Conditioning
The PIC16C54T-HSE/SS can interface to simple analog and digital sensors where on-chip computation exceeds the cost of dedicated signal-conditioning ICs. With 12 I/O pins, the device can read multiple thermistor or switch inputs, perform linearization in firmware, and drive indicator LEDs or display segments. The 8-bit RTCC timer is useful for pulse counting from flow meters, encoders, or PIR motion sensors. The 20 MHz clock enables averaging of multiple ADC samples (via an external ADC) for noise reduction. OTP EPROM suits deployed sensor nodes where firmware is locked at production. The HSE temperature grade allows outdoor or industrial sensor installations.
Recommended
Battery-Friendly Event-Driven Devices
The PIC16C54T-HSE/SS is fully static, meaning the clock can be stopped and restarted without losing register state, enabling event-driven or sleep-wake applications. While it lacks a deep-sleep peripheral, the low CMOS quiescent current and ability to halt the oscillator make it viable for battery-powered devices such as remote controls, simple wireless sensor tags, or electronic doorbells. An external interrupt or RTCC wake-up event restarts the 20 MHz clock, and the 200 ns instruction cycle resumes deterministic operation. The 25-byte RAM is ample for short event logs or timing variables, and the 12 I/O pins support keypad, LED, and IR transmitter or receiver interfaces. The SSOP-20 package supports compact handheld enclosures.
Recommended
Educational and Hobbyist Embedded Projects
The PIC16C54T-HSE/SS remains a popular choice for educational labs, hobbyist projects, and university embedded systems courses due to its simple RISC architecture with only 33 instructions. Students can learn microcontroller fundamentals - I/O, timers, interrupts, watchdog, and OTP programming - without complex peripherals. The SSOP-20 package is breadboard-compatible with adapter boards, and the 20 MHz speed demonstrates the full PIC16C5X instruction-set performance. The OTP EPROM teaches the difference between one-time programmable and Flash memory, emphasizing the importance of code validation. Compatibility with Microchip's PICkit programmers and the MPLAB IDE (legacy) supports classroom toolchains.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C54T-HSE/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C54CT-20E/SS | PIC16C54C-20E/SS | PIC16C54A-20E/SS | PIC16C54C-20I/SS | PIC16C54AT-20E/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | 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 | 20-SOIC - wider body |
| Program Memory | 768 B OTP | 768 B OTP | 768 B OTP | 768 B OTP | 768 B OTP | 768 B OTP |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Temperature Grade | -40 to +125 C (Automotive) | -40 to +125 C | -40 to +125 C | -40 to +125 C | -40 to +85 C (Industrial) | -40 to +125 C |
| RAM | 25 B | 25 B | 25 B | 25 B | 25 B | 25 B |
| Number of I/O | 12 | 12 | 12 | 12 | 12 | 12 |
| Watchdog Timer | Yes | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- Automotive HSE temperature grade qualified (vs PIC16C54C-20I/SS)
- Tape and reel packaging for high-volume SMT (vs PIC16C54C-20E/SS)
- Compact SSOP-20 footprint for space-constrained designs (vs PIC16C54AT-20E/SO)
Design Notes
Place a 100 nF ceramic decoupling capacitor as close as possible to the VDD pin (pin 17) and a bulk capacitor (4.7 to 10 uF) on the supply rail. The PIC16C5X family draws brief current spikes during oscillator transitions; inadequate decoupling causes POR events and code execution anomalies. For automotive 12 V supply environments, add a 5 V LDO (e.g. MCP1700) and a TVS diode to clamp load-dump transients before they reach the MCU.
The PIC16C54T-HSE/SS uses OTP EPROM, which is one-time programmable. Code cannot be erased or rewritten - any bug in the firmware becomes a permanent hardware failure. Always prototype with a windowed CERDIP (PIC16C54C/JW) or a Flash-based PIC16F54 before committing to OTP volume programming. Once an OTP device is programmed and verified, the only way to change the code is to scrap the part. Source: Microchip PIC16C5X datasheet (DS30044E).
Keep the external crystal or ceramic resonator traces from OSC1 (pin 16) and OSC2 (pin 15) as short as possible, with a ground guard ring around the oscillator area. The HSE (HS) oscillator mode at 20 MHz is sensitive to stray capacitance above ~5 pF, which can shift frequency or fail to start. Place load capacitors (typically 15-33 pF for a 20 MHz crystal) directly at the MCU pins with their grounds returned to the VSS pin (pin 5 or 14) via a short, wide trace.
Estimated: at the maximum 20 MHz clock and 5.5 V supply, the PIC16C54T-HSE/SS draws approximately 5 mA active current, dissipating 27.5 mW - well within SSOP-20 thermal limits. The HSE temperature grade supports -40 C to +125 C junction operation. For applications near the temperature extremes, derate clock frequency slightly to reduce internal heating; consult the PIC16C5X datasheet (DS30044E) electrical characteristics for the temperature-frequency tradeoff curve.
Compliance Information
RoHS compliance per Microchip product page. The HSE automotive temperature grade is qualified for automotive use, but AEC-Q100 explicit qualification status is not separately documented for this OTP variant - confirm with Microchip for safety-critical automotive designs.
