PIC16LC774/PT - 8-bit MCU, 7KB OTP, 20MHz, 44-TQFP | Microchip
MPN: PIC16LC774/PT ✗ Cuối đờiPIC16LC774/PT Tóm tắt
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory, working RAM, and peripheral interfaces onto one silicon die. Microcontrollers belong to the broader category of embedded processors, sitting alongside microprocessors (MPUs), DSPs, and SoCs; PIC microcontrollers occupy the 8-bit RISC niche, where deterministic instruction timing and minimal external component count are favored over raw compute throughput. The '16' in PIC16LC774 denotes the mid-range PIC family that uses a 14-bit instruction word, providing 35 single-word instructions and predictable single-cycle execution (branches take two cycles).
Key specifications include 7KB OTP program memory organized as 4K x 14 bits, 256 x 8 bytes of data RAM, four 8-bit I/O ports (PORTA-PORTE partial) yielding 33 usable I/O, a hardware USART, a 10-bit ADC (typically 8 channels on this die), and two Capture/Compare/PWM modules. The OTP memory is one-time programmable, meaning code is locked at production programming time and cannot be field-updated — a key selection criterion versus flash-based PIC16F variants.
Architecturally, the device uses a Harvard architecture with separate program and data buses, enabling simultaneous instruction fetch and operand access. The 20 MHz oscillator drives an internal four-phase clock, and most instructions complete in one oscillator period (200 ns at 20 MHz), with branches taking two periods. The CMOS 'LC' process reduces active and standby draw compared to the original PIC16C77, which made this part attractive for battery-influenced designs.
Typical applications include industrial control and instrumentation, automotive body and chassis subsystems, appliance control boards, sensor interface front-ends, and general-purpose embedded logic replacement. The 33 I/O pins comfortably drive LED arrays, keypads, character LCDs, and simple actuator bridges. The wide operating temperature range also supports outdoor and harsh-environment deployments.
When laying out, allocate a continuous ground pour beneath the device and route the MCLR reset line away from switching nodes to avoid spurious resets. Place the oscillator crystal within 5 mm of OSC1/OSC2 with a grounded guard ring to suppress EMC pickup. Bulk decoupling of 10 uF plus 0.1 uF ceramic at VDD is recommended per Microchip mid-range reference designs.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone — including a parametric comparison table against other 44-TQFP PIC16 family members and same-package drop-in replacements.
Bộ thay thế dễ dàng lắp đặt cho PIC16LC774/PT — 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 PIC16LC774/PT (cùng hình factor và footprint) — khác nhau ở Program Memory Size, Core Architecture, Instruction Cycle Time, Operating Temperature, Package.
PIC16LC774-I/PT
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16LC774T-I/PT
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16LC65A-04I/PT
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
PIC16F877-I/PT
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC16F874A-I/PT
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
PIC16LC774/PT Tỷ lệ tối đa & tính chất điện
| Core Architecture | 8-bit RISC (PIC16 mid-range, 14-bit instruction word) |
| Instruction Set | 35 single-word instructions |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 7 KB (4K x 14) |
| Data RAM | 256 x 8 bytes |
| Data EEPROM | Not present (OTP die) |
| Tần số xung maksimum | 20 MHz |
| Instruction Cycle Time | 200 ns (4 TCY per oscillator period) |
| I/O Pins | 33 |
| Capture/Compare/PWM Modules | 2 (typical for PIC16C77 family) |
| USART | 1 x hardware USART (AUSART) |
| Hộp | 44-pin TQFP (10 x 10 mm) |
| Kiểu lắp đặt | Surface Mount |
Hướng dẫn cấu hình chân PIC16LC774/PT 44-pin tqfp (10 x 10 mm)
Cấu hình chân cho PIC16LC774/PT (44-pin tqfp (10 x 10 mm) gói). IC số này bao gồm chân GPIO, giao diện truyền thông (UART, SPI, I2C) và chân nguồn. Tham khảo tài liệu thông số kỹ thuật của nhà sản xuất để biết các chức năng chân thay thế và tùy chọn cấu hình. Cực kỳ quan trọng cho thiết kế hệ thống tích hợp và lập trình PCB.
Không có dữ liệu chân cụ thể sẵn có cho PIC16LC774/PT.
Tham khảo: tài liệu kỹ thuật cho cấu hình chân đầy đủ.
Ứng dụng tiêu biểu
PIC16LC774/PT phù hợp cho 6 Áp dụngs: Industrial Process Control, Automotive Body and Chassis Electronics, Appliance Control Boards, Sensor Interface Front-Ends, General-Purpose Embedded Logic Replacement, HMI and Display Controllers.
Industrial Process Control
The PIC16LC774/PT is well suited for industrial process controllers driving sensors, valves, and indicator panels. With 33 I/O pins the device can scan a 4x4 keypad, drive a 16x2 character LCD, and read multiple analog inputs through the on-chip 10-bit ADC without external multiplexer expansion. The 20 MHz clock keeps control-loop latency under 200 ns per instruction, deterministic enough for PID loops on slow thermal and pressure processes. Its 5 V supply is native to legacy 24-V industrial backplanes stepped down to logic levels, and the 44-TQFP package supports dense multi-board layouts inside sealed enclosures.
Được đề xuất
Automotive Body and Chassis Electronics
The PIC16LC774/PT historically powered body controllers, lighting modules, and simple wiper/window controls in pre-CAN automotive designs. Its wide operating voltage tolerance and deterministic interrupt response make it appropriate for seat-controller and mirror-adjust nodes that run from 12 V battery rails. The 256-byte RAM is sufficient for state machines governing lighting sequences and door-lock actuators. While newer automotive designs migrate to dsPIC33CH and PIC18F-K80 families, the LC774 remains in NRND service for legacy spare-part channels and aftermarket modules where exact form-fit-function is mandated.
Được đề xuất
Appliance Control Boards
White-goods manufacturers deployed the PIC16LC774/PT in washing-machine, dishwasher, and oven control boards where cost dominates over flash reprogrammability. The 33 I/O lines drive seven-segment displays, keypads, relay coils, and triac-fired heater loads through zero-cross optoisolators. The OTP memory locks firmware at production, preventing field tampering with safety-critical parameters like maximum heater-on time. Five-volt operation aligns with the regulated logic rail that already powers the user-interface MCU cluster, simplifying BOM. Its NRND status today means most new appliance designs migrate to PIC16F or PIC18F equivalents.
Được đề xuất
Sensor Interface Front-Ends
The PIC16LC774/PT serves as a sensor-hub MCU aggregating thermocouple, RTD, and 4-20 mA loop inputs in distributed measurement nodes. Its 10-bit ADC and 33 digital I/O enable multiplexing eight analog channels plus a UART link back to a central controller. The LC low-power CMOS process reduces quiescent draw compared to the older PIC16C77 NMOS variant, which matters in solar-powered remote sensors. With 256 bytes of RAM the device can buffer a small calibration table and run linearization routines on cold-junction-compensated thermocouple readings. The 44-TQFP exposes enough I/O to also drive status LEDs and a local LCD.
Được đề xuất
General-Purpose Embedded Logic Replacement
Designers frequently replace discrete 74HC logic gates and small PLDs with the PIC16LC774/PT when firmware-driven behavior is preferable to hard-wired glue logic. A single MCU in a 44-TQFP can replace dozens of discrete packages, shrinking PCB area and reducing assembly cost. The 20 MHz clock executes 5 MIPS, enough for state-machine timing, debounce filtering, and serial protocol generation. The 33 I/O pins can sink or source 25 mA each, sufficient for direct LED drive without external transistors. For retrofit designs that must exactly replicate legacy LC774 firmware, no silicon alternative preserves pinout and register map as cleanly as another member of the PIC16LC77x family.
Được đề xuất
HMI and Display Controllers
The PIC16LC774/PT is widely deployed as a low-cost HMI controller for character LCDs, seven-segment panels, and small graphical OLEDs in industrial terminals. The 33 I/O pins support a parallel 4-bit or 8-bit LCD interface plus a 4x4 matrix keypad with minimal pin sharing, leaving additional lines for backlight PWM via one of the CCP modules. With 256 bytes of RAM the device can hold menu state, edit-buffer characters, and modest custom-font tables for graphical displays. The 20 MHz clock drives SPI or I2C buses at standard rates, and the hardware USART simplifies connection to upstream PLCs.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC16LC774/PT — 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 | PIC16LC774-I/PT | PIC16LC774T-I/PT | PIC16LC65A-04I/PT | PIC16F877-I/PT | PIC16F874A-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 | 7 KB OTP | 7 KB OTP | 7 KB OTP | 4K x 14 OTP | 8K x 14 Flash | 7K x 14 Flash |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Memory Type | OTP (one-time programmable) | OTP | OTP | OTP | Flash | Flash |
| Operating Temperature Grade | Commercial (0C to +70C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) |
| Lifecycle Status | NRND | NRND | NRND | NRND | Active | Active |
Bảo phân biệt quan trọng
- Low-power CMOS process with industrial temperature option (vsPIC16LC774-I/PT)
- Field-upgradable flash alternative in same footprint (vsPIC16F877-I/PT)
- Established distributor inventory at NRND stage (vsPIC16LC773T-I/SO)
Ghi chú thiết kế
Estimated: Power-supply decoupling on the PIC16LC774/PT requires at minimum one 10 uF tantalum or aluminum bulk capacitor plus a 0.1 uF ceramic placed within 5 mm of the VDD pin. According to the Microchip PIC16C77 family datasheet, mid-range PICs draw brief current spikes of 20-40 mA during instruction execution; insufficient bulk decoupling will cause VDD droop that resets the device under heavy I/O switching load. Add a ferrite bead on VDD if the supply is shared with inductive loads.
Route the MCLR reset pin away from switching nodes and any high-current traces. Place the crystal or resonator within 5 mm of OSC1/OSC2 and surround both oscillator traces with a grounded guard ring to suppress EMC pickup. The 44-TQFP package's exposed thermal pad (where present) should be soldered to a grounded copper pour to reduce junction temperature; this matters in enclosed industrial enclosures where ambient can approach 60 C.
OTP memory cannot be erased or rewritten — a programming error or firmware bug bricks the part permanently. Always program production parts only after a fully validated firmware image has been bench-tested on flash-based PIC16F877-I/PT equivalents. Configure the CONFIG bits (oscillator selection, watchdog enable, brown-out voltage, code protection) carefully; an unintended code-protect setting can lock the device with bad firmware. Use Microchip's MPLAB X IDE with a verified programmer for development, not an off-brand toolchain.
Estimated: The PIC16LC774/PT at 20 MHz and 5 V with all 33 I/O toggling at full CMOS load dissipates roughly 50-80 mW. The 44-TQFP package has a theta_JA of approximately 50 C/W on a standard JEDEC 2S2P board, yielding a junction-to-ambient rise of 3-4 C. This is well within the commercial 0 C to +70 C grade; for industrial -40 C to +85 C parts in sealed enclosures, derate by 10-15 C and ensure adequate ventilation or attach a small clip-on heatsink if ambient exceeds 60 C.
Thông tin tuân thủ
RoHS, lead-free and halogen-free status not directly stated in the verified web data; compliance must be confirmed against the manufacturer's product page or full datasheet. AEC-Q100 not qualified — automotive designs should verify grade or use dsPIC33CH family instead.