PIC18LC242T-I/SO - 8-bit PIC MCU, 16KB OTP, 40MHz | Microchip
MPN: PIC18LC242T-I/SO ✓ Hoạt độngPIC18LC242T-I/SO Tóm tắt
An 8-bit PIC microcontroller is a Harvard-architecture RISC device where program and data memories are accessed via separate buses, enabling single-cycle instruction execution. The OTP variant ships factory-programmed and is intended for low-to-mid volume production where firmware does not need post-shipment updates. The PIC18C family extends the original PIC16 instruction set with 16-bit instructions, an 8-bit data path, and a hardware 8x8 single-cycle multiplier, placing it in the broader Microchip MCU taxonomy above baseline PIC16 parts and below the flash-based PIC18F and PIC18K families.
Key features include 22 I/O pins (23 on related datasheet variants), an external oscillator interface that supports 4-10 MHz crystals with PLL active or a 40 MHz external clock, 8-level interrupt priority, and an analog/digital peripheral set that includes capture/compare/PWM modules, a 10-bit ADC, and an MSSP (Master Synchronous Serial Port) for I2C/SPI. Power-fail detection and a programmable brown-out reset (BOR) circuit protect against unstable supply transitions during 4.0V-5.5V operation.
The architecture separates instruction fetch (16-bit) from operand access (8-bit), letting the CPU sustain 10 MIPS throughput at 40 MHz while keeping peripheral and interrupt latency deterministic. Internal oscillator calibration, dual analog comparators, and sleep/idle modes balance compute performance against the low-power envelope needed in industrial and embedded designs.
Typical applications include industrial control loops, automotive body and chassis subsystems (the LC supply range supports 3.0V-5.5V battery-backed operation), consumer white goods, HVAC controls, and power-conversion front-ends where the MSSP drives a digital PFC stage. The wide-body SOIC footprint suits hand-repair and through-hole-compatible assembly lines that prefer surface-mount packages with strong mechanical leads.
Designers should note the LC suffix indicates a low-voltage core (3.0V-5.5V), not the 5.0V-5.5V F variant; mismatching the supply rail is a common bring-up fault. The MSSP module has documented anomalies on certain revisions - engineers should review Microchip silicon errata before locking the firmware design.
This page synthesizes distributor pricing, tape-and-reel packaging options, drop-in alternatives within the PIC18 family, and practical PCB-layout notes not present in the Microchip datasheet.
Bộ thay thế dễ dàng lắp đặt cho PIC18LC242T-I/SO — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với PIC18LC242T-I/SO (cùng hình factor và footprint) — khác nhau ở ADC, Package, RAM Size, Mounting Type, Program Memory Size.
PIC18LC242-I/SO
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC18F2480T-I/SO
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC18LC252T-I/SO
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC18LF2685-I/SO
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC18LC242T-I/SO Tỷ lệ tối đa & tính chất điện
| Core | PIC18 8-bit RISC |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 16 KB (8K x 16) |
| RAM Size | 512 x 8 bytes |
| EEPROM Size | Not present (OTP device) |
| Instruction Width | 16-bit instructions, 8-bit data path |
| Tần số xung maksimum | 40 MHz (10 MIPS) |
| Oscillator Type | External (4-10 MHz with PLL, up to 40 MHz direct) |
| Supply Voltage (VDD) | 3.0 V to 5.5 V (LC suffix) |
| Number of I/O Pins | 22 |
| Interrupt Priority Levels | 8 |
| Hardware Multiplier | Single-cycle 8 x 8 |
| ADC | 10-bit (peripherals vary by speed grade) |
| Hộp / Vỏ | 28-SOIC (0.295 inch / 7.50 mm width) |
| Kiểu lắp đặt | Surface Mount (SOIC wide-body) |
| Khoảng nhiệt độ hoạt động | -40 C to +85 C (Industrial grade) |
| Cấp MSL | 1 (per JEDEC J-STD-020, typical for OTP SOIC) |
| Lead Finish | Matte Tin (Pb-free, per Microchip ordering code suffix) |
| Trạng thái RoHS | Compliant |
Cấu hình chân PIC18LC242T-I/SO
| Chân 1 | MCLR/VPP — Master clear (reset) input / programming voltage |
| Chân 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Chân 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Chân 4 | RA2/AN2/VREF- — PORTA bit 2 / analog input 2 / VREF- |
| Chân 5 | RA3/AN3/VREF+ — PORTA bit 3 / analog input 3 / VREF+ |
| Chân 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Chân 7 | RA5/AN4/SS — PORTA bit 5 / analog input 4 / SPI slave select |
| Chân 8 | VSS — Ground reference |
| Chân 9 | OSC1/CLKIN — Oscillator crystal input / external clock in |
| Chân 10 | OSC2/CLKOUT — Oscillator crystal output / clock out (FOSC/4) |
| Chân 11 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 output / clock in |
| Chân 12 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 input / Capture-Compare-PWM2 |
| Chân 13 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM1 |
| Chân 14 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Chân 15 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Chân 16 | RC5/SDO — PORTC bit 5 / SPI data out |
| Chân 17 | RC6/TX/CK — PORTC bit 6 / UART TX / synchronous clock |
| Chân 18 | RC7/RX/DT — PORTC bit 7 / UART RX / synchronous data |
| Chân 19 | VSS — Ground reference (second VSS pin) |
| Chân 20 | VDD — Positive supply voltage |
| Chân 21 | RB0/INT0 — PORTB bit 0 / external interrupt 0 |
| Chân 22 | RB1/INT1 — PORTB bit 1 / external interrupt 1 |
| Chân 23 | RB2/INT2 — PORTB bit 2 / external interrupt 2 |
| Chân 24 | RB3/INT3/CCP2 — PORTB bit 3 / external interrupt 3 / CCP2 alt |
| Chân 25 | RB4 — PORTB bit 4 |
| Chân 26 | RB5 — PORTB bit 5 |
| Chân 27 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Chân 28 | RB7/PGD — PORTB bit 7 / ICSP data |
Ứng dụng tiêu biểu
PIC18LC242T-I/SO phù hợp cho 6 Áp dụngs: Industrial Sensor Hub, Appliance Control Board, Automotive Body Module, HVAC Damper Actuator, Smart Meter Display Driver, Power Supply PFC Front-End.
Industrial Sensor Hub
The PIC18LC242T-I/SO suits always-powered industrial sensor-hub designs where firmware is locked at production and BOM cost dominates. Its 16 KB OTP holds typical sensor-fusion state machines, the 22 I/O pins drive 4-20 mA loop inputs plus relay outputs, and the 3.0 V-5.5 V supply range operates directly from a 24 V industrial bus stepped down by a small DC-DC converter. The 8-level interrupt priority handles time-critical limit-switch events without jitter. Designers should plan for an external RS-485 transceiver because the MCU's MSSP cannot drive a differential bus directly.
Được đề xuất
Appliance Control Board
In washing-machine, dishwasher, and microwave control boards the PIC18LC242T-I/SO drives triac outputs for heater banks and AC motor relays through opto-isolated I/O. The 16 KB OTP absorbs PID-loop plus timer-state code, while the 10-bit ADC reads thermistor and water-level sensors. Operating from 5 V through an onboard rectifier, the part consumes tens of mA - sufficient headroom for optocoupler LED drive without extra buffers. OTP memory prevents post-shipping field reprogramming, an anti-tamper benefit for safety-critical appliance firmware.
Được đề xuất
Automotive Body Module
Within non-safety automotive body controllers - window lifts, seat adjusters, lighting drivers - the PIC18LC242T-I/SO handles 8-bit logic without the AEC-Q100 cost premium of K-series parts. The MCU operates from a regulated 5 V body bus, and its 22 I/O pins multiplex with LIN-slave transceivers over UART. Designers must add TVS diodes and reverse-battery protection on VDD; the MCU itself has no integrated automotive load-dump resilience. For safety-critical modules, switch to AEC-Q100-qualified PIC18F K-series parts in the same 28-SOIC footprint.
Được đề xuất
HVAC Damper Actuator
Damper-actuator controllers in variable-air-volume HVAC systems use the PIC18LC242T-I/SO as a position-loop controller driving a brushless DC motor through external MOSFETs. The 8-bit PIC18 core executes a PID loop every 10 ms using the 40 MHz clock, while the 10-bit ADC reads the feedback potentiometer for shaft position. OTP memory locks the loop tuning per damper model, reducing field-tampering risk. Industrial-grade -40 C to +85 C operation tolerates rooftop and plenum mounting.
Được đề xuất
Smart Meter Display Driver
Gas and water meter displays use the PIC18LC242T-I/SO as a low-power LCD-segment driver subcontroller, reading the meter's primary measurement ASIC over SPI and refreshing a multi-digit LCD. The 8-bit core handles anti-tamper logging in OTP, and 3.0 V supply tolerance suits battery-backed designs. Because OTP cannot be flashed in the field, end customers cannot modify tariff schedules - a regulatory requirement in some regional metering standards.
Được đề xuất
Power Supply PFC Front-End
Digitally-controlled PFC (Power Factor Correction) front-ends for offline LED drivers and appliance SMPS use the PIC18LC242T-I/SO as a low-cost peak-current-mode controller. The MSSP drives an external PFC gate-driver such as the NCP1339 over SPI, the 10-bit ADC samples rectified mains for zero-cross detection, and the 8-bit core computes the duty cycle at 40 MHz. OTP locks the firmware against end-user modification. For DFP/CCM control loops requiring finer resolution, consider the dsPIC33 family in a larger package.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC18LC242T-I/SO — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | PIC18LC242-I/SO | PIC18F2480T-I/SO | PIC18LC252T-I/SO | PIC18LF2685-I/SO |
|---|---|---|---|---|---|
| Package | 28-SOIC (0.295 inch / 7.50 mm) | 28-SOIC (0.295 inch / 7.50 mm) - same | 28-SOIC (0.295 inch / 7.50 mm) - same | 28-SOIC (0.295 inch / 7.50 mm) - same | 28-SOIC (0.295 inch / 7.50 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 16 KB OTP | 16 KB OTP (identical) | 16 KB Flash (same density, erasable) | 32 KB OTP (+100%) | 96 KB Flash (+500%) |
| Memory Type | OTP | OTP (same) | Flash (updatable) | OTP (same) | Flash (updatable) |
| Maximum Clock | 40 MHz (10 MIPS) | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| Supply Voltage | 3.0 V to 5.5 V | 3.0 V to 5.5 V (same) | 4.0 V to 5.5 V (F variant) | 3.0 V to 5.5 V (LC) | 2.0 V to 3.6 V (LF) |
| CAN Interface | No | No | Optional on die | No | Yes (CAN 2.0B) |
| MSSP Peripheral | Yes (I2C/SPI) | Yes | Yes | Yes | Yes + 2nd MSSP |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
| Packaging Format | Tape & Reel (T suffix) | Tube (no T) | Tape & Reel | Tape & Reel | Tube (no T) |
Bảo phân biệt quan trọng
- Low-voltage LC variant supports 3.0 V to 5.5 V (broader than the F variant's 5.0 V minimum) (vsPIC18F2480T-I/SO)
- Same-die tape-and-reel packaging for fully-automated SMD assembly (vsPIC18LC242-I/SO)
- Lower BOM cost than flash PIC18F family with same PIC18 instruction-set compatibility (vsPIC18LF2685-I/SO)
Ghi chú thiết kế
Place a 100 nF ceramic decoupling capacitor within 5 mm of pins 8 (VSS) and 20 (VDD). Add a 10 uF bulk tantalum or low-ESR aluminum capacitor on the same VDD trace, rated at least twice VDD max. Brown-out reset (BOR) holds the MCU in reset until VDD reaches a stable threshold above 2.7 V; enable BOR in configuration registers to prevent code execution with a partially ramped supply. Estimated: at 40 MHz and 5.0 V VDD, the LC242 draws approximately 25-40 mA total current. Do not share MCU VDD with high-current inductive loads.
Route the crystal traces (OSC1/OSC2, pins 9 and 10) on the top layer only, surrounded by a ground guard ring, with trace length below 10 mm to minimize stray capacitance. Place MCLR (pin 1) with a 10 kohm pullup resistor and a 100 nF capacitor to ground for a clean power-on reset - this is the most common bring-up fault on PIC18 designs. Keep analog traces (RA0-RA5) separated from digital switching lines by a ground pour or at least 3 mm spacing to avoid ADC noise injection.
Do not mistake the LC suffix for a 5V-only part - the LC variant operates 3.0 V to 5.5 V, and substituting an F (5.0V-only) part on a 3.3V rail will halt operation. The MSSP module has documented silicon errata (PIC18C242 MSSP anomaly) on certain silicon revisions per Microchip read-me documents; check the silicon errata before locking the firmware design. OTP memory cannot be reprogrammed - mis-programmed OTPs must be physically replaced. Always prototype with a flash PIC18F2480T-I/SO in the same socket before committing to OTP for production.
When using ICSP (in-circuit serial programming) on production boards, isolate RB6 (PGC, pin 27) and RB7 (PGD, pin 28) from external pull-ups stronger than 10 kohm, otherwise ICSP communication may fail. Add 4.7 kohm series resistors on PGC/PGD lines if your application uses heavy capacitive loading on those pins. Do not use the debugger on pin 1 (MCLR/VPP) with less than 0.5 V margin during programming - VPP can reach 13V on Microchip programmers.
Thông tin tuân thủ
RoHS compliant per Microchip product page declaration, Pb-free matte-tin lead finish. AEC-Q100 not applicable - OTP PIC18C family is not automotive-qualified; for AEC-Q100 designs use PIC18F K-series or dsPIC33. REACH SVHC compliance confirmed via Microchip environmental certification page.
