PIC18LC452-I/PT - 8-bit MCU, 32KB OTP, 40MHz, 44-TQFP | Microchip
MPN: PIC18LC452-I/PT ✓ ActivePIC18LC452-I/PT Overview
An 8-bit microcontroller (MCU) is a programmable computing IC that integrates a CPU, non-volatile program memory, working RAM, and a rich set of peripherals on a single die. PIC18 microcontrollers from Microchip are positioned above baseline PIC16 parts in the hierarchy PIC10/12/16 -> PIC18 -> PIC24 -> dsPIC -> 32-bit MCUs, offering higher clock speeds, more peripherals, and Harvard architecture. They belong to the broader semiconductor and embedded computing category, with typical use cases spanning consumer appliances, industrial control, and automotive sub-systems.
Key features of the PIC18LC452-I/PT include 32KB (16K x 16) OTP for program storage, 1536 bytes of SRAM, 34 I/O lines, an 8-channel 10-bit ADC, two 8-bit and three 16-bit timers, two Capture/Compare/PWM (CCP) modules, a USART with LIN support, MSSP for SPI/I2C, an 8-bit parallel slave port, and a single-cycle hardware multiplier. The instruction set is highly orthogonal with priority-level interrupts and a depth-31 hardware stack, accelerating context save/restore in real-time tasks.
The LC variant is the low-voltage (2.0 V to 5.5 V) part, distinguishing it from the standard PIC18F452 (4.2 V to 5.5 V) and the PIC18C452 (5 V) predecessors. Architecturally it uses 32 KB of OTP rather than Flash, which means the program is written once and cannot be electrically erased - a strong fit for cost-sensitive production volumes where firmware is stable.
Typical applications include industrial sensor interfaces, motor control loops with PWM, battery-powered instrumentation (low-voltage compatibility extends battery life), automotive body controllers (LIN bus), and consumer white goods. Use PIC18LC452-I/PT when production volumes justify OTP and when 40 MHz performance plus C-compiler friendliness are required.
Drop-in alternatives for PIC18LC452-I/PT — 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 PIC18LC452-I/PT (same form factor and footprint) — differing in Package, Timers, Operating Temperature, Data EEPROM, MSL Level.
PIC18F452-I/PT
✅ Drop-InContact for price
View Datasheet →PIC18F442-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F458-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4620-I/PT
✅ Drop-InContact for price
View Datasheet →PIC18F4550-I/PT
✅ Drop-InContact for price
View Datasheet →PIC18F46K22-I/PT
✅ Drop-InContact for price
View Datasheet →PIC18LC452-I/PT Maximum Ratings & Electrical Characteristics
| Program Memory Size | 32 KB (16K x 16) OTP |
| RAM Size | 1.5 KB (1536 bytes) |
| EEPROM Size | 256 bytes |
| CPU Core | 8-bit PIC18 enhanced RISC |
| Maximum Clock Frequency | 40 MHz |
| Instruction Throughput | 10 MIPS |
| Instruction Width | 16-bit |
| Operating Voltage Range | 2.0 V to 5.5 V (LC low-voltage) |
| Number of I/O Pins | 34 |
| ADC | 10-bit, 8 channels |
| Timers | 2 x 8-bit, 3 x 16-bit |
| CCP Modules | 2 (Capture/Compare/PWM) |
| Communication | USART (LIN), MSSP (SPI/I2C), PSP |
| Hardware Multiplier | 8 x 8 single-cycle |
| Package | 44-pin TQFP (PT) |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| Lead-Free / RoHS | Yes (compliant per Microchip product page) |
| ICSP Programming | Yes (in-circuit) |
PIC18LC452-I/PT Pin Configuration
| Pin 1 | MCLR — Master Clear (reset) / ICSP programming voltage input |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2/VREF- — PORTA bit 2 / Analog input 2 / ADC VREF- |
| Pin 5 | RA3/AN3/VREF+ — PORTA bit 3 / Analog input 3 / ADC VREF+ |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / Analog input 4 / SPI slave select |
| Pin 8 | RE0/RD — PORTE bit 0 / Parallel Slave Port read control |
| Pin 9 | RE1/WR — PORTE bit 1 / Parallel Slave Port write control |
| Pin 10 | RE2/CS — PORTE bit 2 / Parallel Slave Port chip select |
| Pin 11 | VDD — Positive supply (2.0 V to 5.5 V) |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKI — Oscillator crystal input / external clock in |
| Pin 14 | OSC2/CLKO — Oscillator crystal output / clock out |
| Pin 15 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock in |
| Pin 16 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 PWM out |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM output |
| Pin 18 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 19 | RD0/PSP0 — PORTD bit 0 / Parallel Slave Port data 0 |
| Pin 20 | RD1/PSP1 — PORTD bit 1 / Parallel Slave Port data 1 |
| Pin 21 | RD2/PSP2 — PORTD bit 2 / Parallel Slave Port data 2 |
| Pin 22 | RD3/PSP3 — PORTD bit 3 / Parallel Slave Port data 3 |
| Pin 23 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 24 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 25 | RC6/TX/CK — PORTC bit 6 / USART TX / USART clock |
| Pin 26 | RC7/RX/DT — PORTC bit 7 / USART RX / USART data |
| Pin 27 | RD4/PSP4 — PORTD bit 4 / Parallel Slave Port data 4 |
| Pin 28 | RD5/PSP5 — PORTD bit 5 / Parallel Slave Port data 5 |
| Pin 29 | RD6/PSP6 — PORTD bit 6 / Parallel Slave Port data 6 |
| Pin 30 | RD7/PSP7 — PORTD bit 7 / Parallel Slave Port data 7 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply (2.0 V to 5.5 V) |
| Pin 33 | RB0/INT0 — PORTB bit 0 / External interrupt 0 |
| Pin 34 | RB1/INT1 — PORTB bit 1 / External interrupt 1 |
| Pin 35 | RB2/INT2 — PORTB bit 2 / External interrupt 2 |
| Pin 36 | RB3/CCP2 — PORTB bit 3 / CCP2 alternate pin |
| Pin 37 | RB4 — PORTB bit 4 (interrupt-on-change) |
| Pin 38 | RB5 — PORTB bit 5 (interrupt-on-change) |
| Pin 39 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 40 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 41 | AVDD — Analog positive supply (tie to VDD) |
| Pin 42 | AVSS — Analog ground (tie to VSS) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC18LC452-I/PT is suitable for 7 applications: Industrial Sensor Interface / Data Acquisition, PWM Motor Control (BLDC / Stepper), Battery-Powered Instrumentation, Automotive LIN Bus Body Controller, Consumer White Goods / Appliance Control, SPI/I2C Sensor Aggregation Hub, Educational / Embedded Learning Platform.
Industrial Sensor Interface / Data Acquisition
The PIC18LC452-I/PT fits industrial 4-20 mA sensor interfaces and multi-channel data-acquisition modules because of its 8-channel 10-bit ADC and 34 digital I/O lines. With 40 MHz / 10 MIPS throughput, the MCU can sample eight sensors at kHz rates while running C-coded signal conditioning. The 2.0 V to 5.5 V LC variant supports battery-backed plant-floor nodes, and the 44-TQFP package allows compact board layouts with room for op-amp front ends. Compared with PIC16 alternatives, PIC18's C-compiler friendliness reduces firmware-development time for sensor-fusion logic.
Recommended
PWM Motor Control (BLDC / Stepper)
The PIC18LC452-I/PT is suitable for small brushed-DC, stepper, or sensorless BLDC motor control thanks to its two CCP modules producing complementary PWMs and three 16-bit timers for precise commutation timing. At 40 MHz the MCU can update PWM duty cycles every 100 ns, supporting 20 kHz switching with low jitter. The 10-bit ADC samples back-EMF or current-sense amplifiers synchronously to the PWM, and 1.5 KB of RAM is sufficient for trapezoidal commutation tables. The 44-TQFP footprint handles up to 1 A driver ICs with adequate copper pour for thermal dissipation.
Recommended
Battery-Powered Instrumentation
The PIC18LC452-I/PT is a strong fit for battery-powered instrumentation thanks to its 2.0 V to 5.5 V operating range, allowing direct connection to 2x AA / 2x AAA alkaline cells or a single Li-ion cell at minimum. Sleep current in the PIC18LC452 family is below 1 uA per Microchip datasheet DS39581, supporting multi-year battery life in data-logger or remote-sensor applications. The 32 KB OTP program memory suits production firmware, and the 10-bit ADC handles thermocouple, thermistor, or strain-gauge signal chains.
Recommended
Automotive LIN Bus Body Controller
The PIC18LC452-I/PT serves automotive LIN (Local Interconnect Network) slave body modules such as window regulators, mirror controllers, and seat-position nodes. The PIC18 USART supports LIN master/slave mode with auto-baud detection per datasheet DS39581, and the 34 I/O pins drive relays and read switches with adequate headroom. The industrial -40 to +85 C temperature grade suits cabin applications; under-hood designs should use the /E (extended) grade or a PIC18F-with-CAN device.
Recommended
Consumer White Goods / Appliance Control
The PIC18LC452-I/PT is well-suited for cost-sensitive white-goods controllers such as washing-machine front panels, dishwasher timers, and microwave oven user interfaces. The 32 KB OTP memory provides a stable, non-reprogrammable firmware at lower per-unit cost than Flash, ideal for high-volume appliances. Its 10-bit ADC reads keypad matrix voltage dividers and temperature sensors, while PWM outputs drive triac-trigger optos and buzzer tones. The 44-TQFP package enables single-sided PCB layouts with through-hole mounting holes for mechanical strength.
Recommended
SPI/I2C Sensor Aggregation Hub
The PIC18LC452-I/PT acts as a sensor hub aggregating SPI or I2C peripherals such as accelerometers, gyroscopes, and EEPROMs into a unified data stream for an upstream processor. The MSSP module supports both SPI master/slave and I2C master/slave modes at up to 400 kHz I2C and 10 MHz SPI per datasheet DS39581, while the 32 KB program memory can host sensor-fusion algorithms. The 1.5 KB RAM buffers multi-sensor frames before forwarding via USART.
Recommended
Educational / Embedded Learning Platform
The PIC18LC452-I/PT is a popular target for university microcontroller courses and hobbyist embedded projects because of its C-friendly PIC18 core, abundant peripherals, and strong Microchip MPLAB X IDE toolchain support. The 40 MHz clock and 32 KB OTP allow realistic real-time programming exercises (PWM, ADC, USART, I2C, SPI) without the cost of an evaluation board. The 44-TQFP package breaks out all 34 I/O plus ICSP pins for breadboard-friendly carrier boards.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LC452-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F452-I/PT | PIC18F442-I/PT | PIC18F458-I/PT | PIC18F4620-I/PT | PIC18F4550-I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-TQFP | 44-TQFP - same | 44-TQFP - same | 44-TQFP - same | 44-TQFP - same | 44-TQFP - same |
| Program Memory | 32 KB OTP | 32 KB Flash | 16 KB Flash | 32 KB Flash | 64 KB Flash | 32 KB Flash |
| RAM Size | 1.5 KB | 1.5 KB | 768 B | 1.5 KB | 3.9 KB | 2 KB |
| Max Clock / MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 48 MHz / 12 MIPS |
| Operating Voltage | 2.0 V to 5.5 V (LC) | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V |
| CAN / USB / Special | None | None | None | CAN 2.0B | None | USB 2.0 FS |
Key Differentiators
- Low-voltage operation down to 2.0 V (vs PIC18F452-I/PT)
- OTP cost reduction at high volume (vs PIC18F452-I/PT)
- Pin-compatible upgrade paths to CAN and USB (vs PIC18F458-I/PT and PIC18F4550-I/PT)
Design Notes
Estimated: at 40 MHz / 5 V the PIC18LC452-I/PT draws approximately 25 mA active per Microchip datasheet DS39581 typical curves. Decouple each VDD/AVDD pair with 100 nF ceramic placed within 5 mm of the pin, plus a bulk 10 uF tantalum or ceramic on the main VDD rail. The AVDD pin must be tied to VDD even if the ADC is unused. Operating at 2.0 V lowers active current to approximately 10 mA, useful for battery designs.
Three common pitfalls when using PIC18LC452-I/PT: (1) OTP can only be programmed once - any code bug in production firmware bricks the device, so prototype with PIC18F452-I/PT first; (2) the LC low-voltage variant cannot operate above 5.5 V, so 6 V or 12 V industrial supplies need a regulator; (3) ICSP programming requires the 13 V high-voltage entry on MCLR, so isolate MCLR from the rest of the reset network with a diode or resistor to avoid programming interference.
Route the 40 MHz oscillator traces short (<5 mm) and guard with ground; place load caps CL1/CL2 (typically 15-33 pF for a 10 MHz crystal) close to OSC1/OSC2. Keep analog traces (RA0-RA5, AVSS) away from digital switching lines to minimize ADC noise coupling - the 10-bit ADC is sensitive to >50 mV digital crosstalk. Route PGC/PGD as a short differential pair for reliable ICSP at production programming.
When using the Parallel Slave Port (PORTD/RE0-ON, RE1, RE2), add 100 ohm series resistors on RD0-RD7 if connecting to a bus >10 MHz to limit ringing. The PSP is rated for 8-bit external memory or FIFO interfacing up to the MCU's system clock. The USART TX/RX pins can be configured as regular digital I/O if unused, freeing RC6/RC7 for other functions.
Compliance Information
RoHS compliant per Microchip product page. Lead-free /Pb-free termination (NiPdAu). Not AEC-Q100 qualified; for automotive AEC-Q100 designs use PIC18F458-I/PT or PIC18F4620-I/PT -Q1 grade. Halogen-free per Microchip packaging declaration.