PIC17C42A-25E/L - 8-Bit 25MHz OTP MCU 4KB PLCC | Microchip
料号： PIC17C42A-25E/L ✗ 停产| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $13.97 | $13.97 |
| 10 | $12.45 | $124.50 |
| 100 | $10.85 | $1,085.00 |
| 500 | $9.6 | $4,800.00 |
| 1,000 | $8.5 | $8,500.00 |
PIC17C42A-25E/L 概述
An 8-bit microcontroller is a small, self-contained computing element built around an 8-bit data bus and Harvard architecture. The PIC17C42A family sits between baseline PIC16C5X and enhanced PIC16CXX devices in the Microchip PIC hierarchy: PIC16C5X (12-bit instructions, OTP/ROM) -> PIC17C42A (16-bit instructions, OTP, 8.25 MIPS) -> PIC18F (16-bit instructions, Flash, >10 MIPS). It uses a RISC core with only 58 single-word instructions, yet offers significantly more horsepower than earlier PIC16 devices, making it suitable for applications that need real-time response without moving to the PIC18 platform.
Key features include a 25 MHz external clock, an 8-level hardware stack, multiple interrupt sources, two 8-bit timer/counters, a 16-bit timer/counter, a synchronous serial port (SSP) supporting SPI/I2C master modes, an 8-bit parallel slave port, and a USART. The device is built on a low-power CMOS process and operates from 4.5 V to 5.5 V. Compared with later PIC18F devices, PIC17C42A offers a wider supply tolerance and a robust 8-bit ALU optimized for byte-oriented control.
Typical applications include industrial control logic, motor control, automotive body electronics, point-of-sale terminals, security panels, and embedded instrumentation. Per Microchip, the recommended migration path is PIC18F4220 - new designs should generally not start on PIC17C42A.
When designing with PIC17C42A-25E/L, note that it is OTP, not Flash - firmware cannot be re-programmed in-circuit. Use the 'E' windowed (UV-erasable) or emulator variants for prototyping. The 44-PLCC footprint is common with PIC17C43/44 devices, allowing pin-compatible upgrades within the family.
直接替换替代料： PIC17C42A-25E/L ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： PIC17C42A-25E/L （相同外形与封装尺寸） ——差异在于 Operating Temperature Range, Package, Peripherals, Oscillator Type, Program Memory Size.
快速对比工具——选择替代料号进行并排对比：
PIC17C42A-25I/L
✅ 直接替换✓ 有现货
$7.2 / 个
查看数据手册 →PIC17C43-25E/L
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$9.78 / 个
查看数据手册 →PIC17C44-25E/L
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
PIC17C42A-25E/P
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$5.6 / 个
查看数据手册 →PIC17C42A-25E/L 最大额定值与电气特性
| Core Architecture | PIC 8-bit RISC |
| Instruction Set Width | 16-bit (58 single-word instructions) |
| 最大时钟频率 | 25 MHz |
| Performance | 8.25 MIPS (121 ns instruction cycle) |
| Program Memory Size | 4 KB (2K x 16), OTP EPROM |
| RAM Size | 232 x 8 bytes (454 bytes user RAM) |
| Number of I/O Pins | 33 |
| 封装 | 44-PLCC (J-Lead), 16.59 x 16.59 mm |
| 安装类型 | Surface Mount |
| Oscillator Type | External |
| Supply Voltage (Vcc) | 4.5 V to 5.5 V |
| 工作温度范围 | -40 C to +85 C (E suffix = industrial) |
| Program Memory Type | OTP EPROM (one-time programmable) |
| Hardware Stack | 8 levels |
| Peripherals | SSP (SPI/I2C), USART, 8-bit Parallel Slave Port, 2x 8-bit + 1x 16-bit Timer |
| RoHS 状态 | Non-compliant (SnPb finish, PLCC windowed ceramic variant exempt) |
| Legacy Replacement Recommendation | PIC18F4220 |
PIC17C42A-25E/L 引脚配置
| 引脚 1 | RA0/INT — PORTA bit 0 / external interrupt input |
| 引脚 2 | RA1 — PORTA bit 1 |
| 引脚 3 | RA2 — PORTA bit 2 |
| 引脚 4 | RA3 — PORTA bit 3 |
| 引脚 5 | RA4/RTCC — PORTA bit 4 / RTCC I/O |
| 引脚 6 | RA5 — PORTA bit 5 |
| 引脚 7 | RA6 — PORTA bit 6 |
| 引脚 8 | RA7 — PORTA bit 7 |
| 引脚 9 | RB0 — PORTB bit 0 |
| 引脚 10 | RB1 — PORTB bit 1 |
| 引脚 11 | RB2 — PORTB bit 2 |
| 引脚 12 | RB3 — PORTB bit 3 |
| 引脚 13 | OSC1 — Oscillator input (external clock) |
| 引脚 14 | OSC2 — Oscillator output (crystal) |
| 引脚 15 | RC0 — PORTC bit 0 |
| 引脚 16 | RC1 — PORTC bit 1 |
| 引脚 17 | RC2 — PORTC bit 2 |
| 引脚 18 | RC3 — PORTC bit 3 |
| 引脚 19 | RC4 — PORTC bit 4 |
| 引脚 20 | RC5 — PORTC bit 5 |
| 引脚 21 | RC6 — PORTC bit 6 |
| 引脚 22 | RC7 — PORTC bit 7 |
| 引脚 23 | RD0 — PORTD bit 0 / PSP |
| 引脚 24 | RD1 — PORTD bit 1 / PSP |
| 引脚 25 | RD2 — PORTD bit 2 / PSP |
| 引脚 26 | RD3 — PORTD bit 3 / PSP |
| 引脚 27 | RD4 — PORTD bit 4 / PSP |
| 引脚 28 | RD5 — PORTD bit 5 / PSP |
| 引脚 29 | RD6 — PORTD bit 6 / PSP |
| 引脚 30 | RD7 — PORTD bit 7 / PSP |
| 引脚 31 | RE0 — PORTE bit 0 |
| 引脚 32 | RE1 — PORTE bit 1 |
| 引脚 33 | VSS — Ground |
| 引脚 34 | VDD — Positive supply (4.5-5.5 V) |
| 引脚 35 | RE2 — PORTE bit 2 |
| 引脚 36 | RE3 — PORTE bit 3 |
| 引脚 37 | RF0 — PORTF bit 0 |
| 引脚 38 | RF1 — PORTF bit 1 |
| 引脚 39 | RF2 — PORTF bit 2 |
| 引脚 40 | RF3 — PORTF bit 3 |
| 引脚 41 | RF4 — PORTF bit 4 |
| 引脚 42 | RF5 — PORTF bit 5 |
| 引脚 43 | RB7/PGM — PORTB bit 7 / low-voltage programming |
| 引脚 44 | RB6/PGC — PORTB bit 6 / ICSP clock |
典型应用
PIC17C42A-25E/L 适用于 6 应用s: Industrial Control Logic, Motor Control (BLDC/Stepper), Point-of-Sale Terminals, Security and Alarm Panels, Automotive Body Electronics, Embedded Instrumentation.
Industrial Control Logic
The PIC17C42A-25E/L is well suited to industrial control logic where deterministic real-time response is required. Its 25 MHz core delivers 8.25 MIPS (121 ns instruction cycle), giving the headroom to scan I/O and execute PID-style control loops within tight millisecond budgets. The 33 digital I/O pins interface directly to 5 V industrial sensors, relays, and triac drivers, while the on-chip USART links to RS-485 transceivers for fieldbus-style wiring. OTP memory locks firmware against field tampering, which is desirable in factory-automation equipment. The 4.5-5.5 V supply tolerance tolerates loosely regulated 5 V industrial rails. Note that new designs should migrate to PIC18F4220 for Flash in-field reprogrammability.
推荐
Motor Control (BLDC/Stepper)
The PIC17C42A-25E/L can drive small BLDC and stepper motors via PWM generated in firmware or with external driver ICs. The 16-bit timer/counter provides the time base for closed-loop commutation, and the two 8-bit timers handle PWM channels. At 25 MHz / 8.25 MIPS the device sustains commutation update rates above 20 kHz, suitable for sub-100 W motors. Per Microchip datasheet DS30412C, the parallel slave port allows a host MCU to stream motion profiles into the PIC17C42A acting as a co-processor. The OTP memory is well suited to fixed motor-control firmware where the program is finalized at production.
推荐
Point-of-Sale Terminals
The PIC17C42A-25E/L has been used historically in point-of-sale terminals where its OTP memory, 5 V I/O, and integrated USART support both magnetic-stripe readers and serial peripherals. The 232 x 8 RAM is sufficient to buffer transaction strings, and 4 KB OTP holds the fixed terminal application. The synchronous serial port (SSP) drives a small SPI display or keyboard scanner, while the parallel slave port connects to the host POS processor for command and response. Its 8.25 MIPS performance handles keystroke debounce and packet framing without DMA. Modern POS designs use Flash-based MCUs, so PIC17C42A is now seen mainly in legacy equipment sustaining existing fleets.
推荐
Security and Alarm Panels
The PIC17C42A-25E/L is well matched to security panel applications: deterministic 8.25 MIPS performance guarantees scan loops run on schedule; OTP memory locks firmware to prevent field tampering; and 33 I/O easily accommodates 8-16 zone inputs plus keypad, siren, and dialer outputs. The integrated USART supports digital alarm communicators over the phone line via a modem chip. The parallel slave port enables a touchscreen or LCD module to share I/O with the panel CPU. PIC17C42A's wide 4.5-5.5 V supply tolerance works directly with lead-acid battery-backed 5 V rails common in fire and security panels. New security panels use Flash MCUs to enable remote firmware updates.
推荐
Automotive Body Electronics
Automotive body controllers, HVAC panels, and instrument clusters historically employed PIC17C42A-25E/L at 25 MHz for deterministic control of relays, lamps, and displays. Its 5 V digital I/O is well matched to body-electronics drivers like the VNQ500 or BTS432E, while the on-chip timers and PWM channels drive stepper motors in instrument clusters. The 'I' temperature grade variant supports -40 C to +125 C ambient conditions. Note that modern automotive designs require AEC-Q100 qualification, which PIC17C42A does not carry; new automotive programs should use qualified Flash MCUs such as PIC18F4580-I/PT.
推荐
Embedded Instrumentation
Embedded instrumentation such as bench-top meters, lab data loggers, and process controllers benefit from the PIC17C42A-25E/L's deterministic 8.25 MIPS core, USART, and parallel slave port. The USART connects to RS-232 instruments or RS-485 multi-drop networks; the parallel slave port interfaces to graphic LCD controllers or external data acquisition front-ends. 4 KB OTP comfortably stores fixed calibration tables and menu code, while 232 x 8 RAM buffers measurement strings. The wide 4.5-5.5 V supply tolerance works with unregulated instrumentation rails. Modern data loggers use Flash-based PIC18 or dsPIC parts, so PIC17C42A appears mainly in legacy instruments with stable firmware.
推荐
推荐产品汇总
工程参考数据： PIC17C42A-25E/L ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | PIC17C42A-25I/L | PIC17C43-25E/L | PIC17C44-25E/L | PIC17C42A-25E/P |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 40-PDIP (different package) |
| Program Memory | 4 KB OTP (2K x 16) | 4 KB OTP | 8 KB OTP | 16 KB OTP | 4 KB OTP |
| RAM | 232 x 8 | 232 x 8 | 454 x 8 | 454 x 8 | 232 x 8 |
| Clock Frequency | 25 MHz | 25 MHz | 25 MHz | 25 MHz | 25 MHz |
| Operating Temperature | -40 C to +85 C | -40 C to +125 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete |
关键差异点
- Drop-in PIC17 family member with extended industrial temperature grade （对比 PIC17C42A-25I/L)
- Double the program memory in the same PLCC package （对比 PIC17C43-25E/L)
- Quadruple program memory in same PLCC package （对比 PIC17C44-25E/L)
设计说明
PIC17C42A-25E/L is OTP - firmware cannot be re-programmed in-circuit. If there is any chance of firmware revision during development, use the JW windowed ceramic variant or a modern PIC18F4220 flash MCU instead. Programming requires a Microchip PIC17 programmer (e.g., PIC17C-PROG) targeting the LVP/PGC/PGM pins; the high-voltage parallel programming algorithm differs from PIC18.
Decouple VDD with a 0.1 uF ceramic capacitor placed within 1 cm of pin 34, plus a 10 uF bulk electrolytic or tantalum near the IC. The PIC17C42A datasheet recommends a 1k-ohm pull-up on MCLR with a 0.1 uF capacitor to VDD for proper power-on reset. Operating supply is 4.5 V to 5.5 V; under-voltage operation may cause program counter corruption in the 8-level hardware stack without raising an interrupt.
The 44-PLCC J-lead footprint has wider pads (about 0.045 in lead pitch) than QFP/QFN packages, so verify the PCB land pattern matches PLCC-44 rather than QFP-44 - they look similar but PLCC pads extend outward while QFP pads are inward-gullwing. Provide a generous copper pour under the PLCC socket for thermal spreading; the OTP die has moderate thermal resistance. Trace OSC1/OSC2 to a crystal/capacitor network within 1 cm; long oscillator traces pick up noise and cause instruction-cycle jitter.
合规信息
Microchip's OTP PLCC family uses SnPb lead finish and is generally not RoHS compliant; new designs should migrate to PIC18F4220 which is RoHS compliant. AEC-Q100 qualification not documented; choose PIC18F4580-I/PT for AEC-Q100 automotive programs.
