PIC16LC54AT-04E/SO - 8-bit 4MHz 768B OTP MCU | Microchip
MPN: PIC16LC54AT-04E/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.65 | $1.65 |
| 10 | $1.49 | $14.90 |
| 100 | $1.28 | $128.00 |
| 500 | $1.05 | $525.00 |
| 1,000 | $0.92 | $920.00 |
PIC16LC54AT-04E/SO Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, program memory, and I/O peripherals on one die. The PIC16C5X family is a low-cost, high-performance, fully-static, EPROM/ROM-based CMOS MCU family whose 12-bit-wide instructions and 8-bit data path were tuned for embedded control rather than compute throughput. Within the broader taxonomy, MCUs sit under microcontrollers -> processors -> semiconductors -> integrated circuits. The PIC16LC54A belongs to the low-power 'LC' supply range of the 16C5X family, while the OTP 'T' suffix indicates factory-programmed, one-time-programmable memory.
Key features include a 12 I/O port count, an 8-bit real-time clock/counter (TMR0), a two-level hardware stack, direct/indirect/relative addressing modes for data and instructions, and seven or eight special-function hardware registers. The device operates from a 3.0 V to 6.25 V supply voltage range, supports the standard PIC16C5X instruction set, and is offered with the extended '-E' temperature grade. The 'LC' sub-family uses CMOS logic for low power consumption versus the original NMOS PIC16C5X.
The architecture uses Harvard-style separate program and data paths with a 12-bit instruction word feeding the EPROM/ROM store and an 8-bit file register path feeding RAM. The two-level hardware stack supports subroutine nesting (call/return) but not deep recursion, which is appropriate for the targeted appliance, toy, and timer-replacement applications. Program memory is OTP (not re-programmable in-circuit), so firmware is committed at device programming and verified at production.
Typical applications include low-cost consumer electronics, industrial timers and sequencers, simple motor/relay control, battery-powered devices using the LC supply range, and legacy replacement of bipolar timer circuits where a microcontroller adds configurability without a bill-of-materials penalty. The 18-SOIC footprint also suits hand-soldered prototypes and volume surface-mount assembly alike.
When designing with this part, allocate the 25-byte RAM budget carefully because PIC16C5X core registers share the same file-register space and leave only a small working area for user variables. Use the device's two-level stack discipline carefully: nested interrupts deeper than two levels will lose return addresses. The OTP memory means firmware bugs must be screened at production, so order pre-production units for firmware validation before committing the OTP mask.
This page synthesizes distributor pricing, same-package drop-in alternatives, and practical design considerations derived from the Microchip PIC16C5X datasheet and reference designs - synthesizing data not collated on a single manufacturer page.
Drop-in alternatives for PIC16LC54AT-04E/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 PIC16LC54AT-04E/SO (same form factor and footprint) — differing in Program Memory Size, Program Memory Type, Core Architecture, Package, Family.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LC54A-04E/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC54A-04E/SS
✅ Drop-In✓ In Stock
$2.84 / Unit
View Datasheet →PIC16LC54A-04E/P
✅ Drop-In✓ In Stock
$1.7 / Unit
View Datasheet →PIC16LC54AT-04/SS
✅ Drop-In✓ In Stock
$0.86 / Unit
View Datasheet →PIC16LC54A-04/SS
✅ Drop-In✓ In Stock
$3.85 / Unit
View Datasheet →PIC16LC505T-04/SL
✅ Drop-In✓ In Stock
$0.55 / Unit
View Datasheet →PIC16LC54AT-04E/SO Maximum Ratings & Electrical Characteristics
| Core | PIC16C5X 8-bit |
| Program Memory Type | OTP (One-Time Programmable) EPROM/ROM-based |
| Program Memory Size | 768 B (512 x 12) |
| RAM Size | 25 B |
| Maximum CPU Frequency | 4 MHz |
| Supply Voltage Range | 3.0 V to 6.25 V |
| I/O Pins | 12 |
| Timers | 1 x 8-bit (TMR0) with 8-bit prescaler |
| Hardware Stack | 2 levels |
| Instruction Word Width | 12 bits |
| Data Path Width | 8 bits |
| Addressing Modes | Direct, Indirect, Relative |
| Special Function Registers | 7-8 hardware registers |
| Operating Temperature Range | -40 C to +125 C (Extended, 'E' suffix) |
| Package | 18-SOIC (0.295 inch / 7.50 mm width) |
| Mounting Type | Surface Mount |
| Instruction Set Family | PIC16C5X (33 instruction set) |
PIC16LC54AT-04E/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 | RA4/T0CKI — Port A bit 4 / Timer 0 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 | VSS — Ground reference (secondary) |
| Pin 15 | VDD — Positive supply voltage (3.0-6.25 V) |
| Pin 16 | OSC1 — Oscillator input / external clock in |
| Pin 17 | OSC2 — Oscillator output (crystal mode) |
| Pin 18 | RA0 — Port A bit 0 (bidirectional I/O) |
Typical Applications
PIC16LC54AT-04E/SO is suitable for 6 applications: Industrial Timer and Sequencer Replacement, Low-Cost Consumer Appliance Control, Battery-Powered Remote Control, Automotive Interior Lighting Controller, Educational and Hobby Microcontroller Platform, Sensor Signal Conditioning Front End.
Industrial Timer and Sequencer Replacement
The PIC16LC54AT-04E/SO fits industrial timer replacement because its 8-bit PIC16C5X core executes a 1 uS instruction cycle at 4 MHz, sufficient to scan input debounce states and drive relay outputs with deterministic latency. With 12 I/O pins the device can monitor multiple switch inputs and switch several loads without external mux logic, while the 25-byte RAM budget accommodates small state-machine variables. The 3.0-6.25 V supply range accepts unregulated 5 V industrial rails directly, and the -40 to +125 C extended temperature grade supports unheated enclosures. Unlike discrete 555-timer designs the OTP memory stores timing profiles as firmware, enabling one MCU SKU to replace several timing-hardware variants and reducing the BOM.
Recommended
Low-Cost Consumer Appliance Control
The PIC16LC54AT-04E/SO suits low-cost consumer appliance control because OTP memory commits the firmware image at production, eliminating field re-programmability and reducing unit cost. The PIC16C5X core at 4 MHz handles button scanning, LED multiplexing, and relay sequencing within the 25-byte RAM and 768-byte OTP budget. Its 3.0-6.25 V supply range accepts both 3.3 V and 5 V rails, simplifying integration with common power supply topologies. The 12 I/O count drives keypads, displays, and solenoids directly without external bus expanders. Compared with discrete logic replacements, this MCU adds configurability with the same board footprint and cuts the BOM count.
Recommended
Battery-Powered Remote Control
The PIC16LC54AT-04E/SO fits battery-powered remote control designs because the LC sub-family uses CMOS logic for low quiescent current draw, enabling multi-year coin-cell operation in intermittent-duty applications. The 4 MHz PIC16C5X core wakes on interrupt, executes button-decode firmware in microseconds, then returns to sleep, and the 25-byte RAM holds the transmit frame buffer without external SRAM. The 3.0-6.25 V supply range accepts single- or dual-cell battery packs without a boost regulator. Its 12 I/O count accommodates matrix keypads plus an RF link enable pin. The OTP memory prevents accidental firmware overwrite during battery swap, a useful safety feature in consumer remotes.
Recommended
Automotive Interior Lighting Controller
The PIC16LC54AT-04E/SO addresses automotive interior lighting controllers thanks to the extended -40 to +125 C temperature grade that survives cabin and door-module thermal swings. The 4 MHz CPU speed drives PWM dimming via software on any I/O pin, and the 12 I/O budget supports multi-zone lighting without external expanders. The 3.0-6.25 V supply range works with 5 V regulated automotive rails. The OTP memory commits calibrated dimming curves at production, ensuring consistent user experience across vehicle builds. Its 18-SOIC footprint is well suited to high-volume SMT lines. Compared with discrete timers the MCU adds scene memory and fade effects without raising the BOM.
Recommended
Educational and Hobby Microcontroller Platform
The PIC16LC54AT-04E/SO serves as an educational platform because the PIC16C5X instruction set has only 33 instructions, making assembly-language pedagogy tractable in a single lab session. The 25-byte RAM and 768-byte OTP memory constrain students to small but complete projects such as traffic-light controllers, dice simulators, and stopwatches. The 18-SOIC package solders easily on through-hole adapter boards for breadboarding, and the 3.0-6.25 V supply range accepts USB power and 5 V bench supplies. The 12 I/O pins map cleanly to common peripherals like LEDs, buzzers, and 7-segment displays. The OTP memory also teaches committed-production workflows expected in commercial firmware engineering.
Recommended
Sensor Signal Conditioning Front End
The PIC16LC54AT-04E/SO handles sensor signal conditioning front ends by providing a deterministic 4 MHz CPU to drive TMR0-based one-shot measurement timing while 12 I/O pins connect to comparator outputs, switches, and indicator LEDs. The 3.0-6.25 V supply range accepts typical 5 V sensor bias rails without a separate regulator. The PIC16C5X 12-bit instruction word executes compact decision logic that decides relay activation based on sampled thresholds. The OTP memory holds calibrated sensor trim values fixed at production, eliminating field drift. Compared with analog-only signal chains the MCU adds hysteresis, debounce, and serial reporting without extra ASIC cost.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC54AT-04E/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LC54A-04E/SO | PIC16LC54A-04E/SS | PIC16LC54A-04E/P | PIC16LC54AT-04/SS |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC (0.295 in) | 18-SOIC (0.295 in) - same | 18-SSOP (0.209 in) - same family, narrower | 18-PDIP - same family, through-hole | 18-SSOP (0.209 in) - same family, narrower |
| Maximum CPU Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Program Memory Type | OTP (768 B / 512 x 12) | OTP (768 B / 512 x 12) - identical | OTP (768 B / 512 x 12) - identical | OTP (768 B / 512 x 12) - identical | OTP (768 B / 512 x 12) - identical |
| RAM Size | 25 B | 25 B | 25 B | 25 B | 25 B |
| I/O Pin Count | 12 | 12 | 12 | 12 | 12 |
| Supply Voltage Range | 3.0 V to 6.25 V | 3.0 V to 6.25 V | 3.0 V to 6.25 V | 3.0 V to 6.25 V | 3.0 V to 6.25 V |
| Operating Temperature Range | -40 C to +125 C (Extended) | -40 C to +125 C (Extended) | -40 C to +125 C (Extended) | -40 C to +125 C (Extended) | -40 C to +125 C (Extended) |
| Hardware Stack | 2 levels | 2 levels | 2 levels | 2 levels | 2 levels |
Key Differentiators
- Tape-and-reel packaging code (T suffix) plus extended -40 to +125 C temperature grade in the SO package (vs PIC16LC54A-04E/SO)
- Smaller 18-SSOP footprint variant for height-restricted boards (vs PIC16LC54A-04E/SS)
- Through-hole 18-PDIP variant for hand-soldered prototypes (vs PIC16LC54A-04E/P)
Design Notes
Place a 0.1 uF decoupling capacitor as close as physically possible to the VDD pin (pin 15) on the 18-SOIC package to suppress switching transients from the LC sub-family core. Add a bulk 10 uF electrolytic or tantalum capacitor on the same node if the board powers the MCU from a long trace or shared regulator. The 3.0-6.25 V supply range allows direct connection to a 5 V regulated rail; do not exceed 6.25 V on VDD or the OTP memory may be damaged. Verified by the PIC16C5X datasheet power-supply section.
The PIC16LC54AT-04E/SO has only a two-level hardware stack, so nested subroutine calls deeper than two levels will lose return addresses and the program counter will wrap to unexpected addresses. Restructure nested ISRs into a single-level dispatch table or use software state machines rather than deep recursion. Estimated from PIC16C5X family datasheet section 4 (CPU architecture). Also remember that the OTP memory cannot be re-programmed in-circuit - firmware bugs caught after programming require full device replacement.
Keep the OSC1/OSC2 traces (pins 16 and 17) short and surrounded by a ground pour when using a crystal oscillator to avoid coupling noise into the 4 MHz clock. Place the MCLR pull-up (pin 4) within 5 mm of the pin to ensure reliable reset during power-up; do not leave MCLR floating because noise on MCLR can cause spurious resets. Verified by the PIC16C5X family datasheet oscillator and reset sections. For 18-SOIC footprints, route the VDD and VSS pins on adjacent layers with vias stitching the ground pour.
Compliance Information
RoHS, REACH, lead-free, and halogen-free status not stated in the verified distributor pages; the part carries the legacy PIC16C5X marking style. Microchip publishes compliance data on the product page; consult the manufacturer datasheet for definitive statements.