PIC16C745/JW - 8-Bit 24MHz USB MCU, 14KB EPROM, 28-CerDip | Microchip
MPN： PIC16C745/JW ✗ 停產PIC16C745/JW 概覽
An 8-bit microcontroller is a single-chip computer that processes data 8 bits at a time using a RISC or CISC instruction set, and it sits in the broader hierarchy of microcontrollers -> embedded controllers -> semiconductor ICs. The PIC16C745 belongs to Microchip's PIC16 mid-range family, which is positioned between the baseline PIC10/PIC16 and the high-performance PIC18 lines. This positions the part as a low-cost, OTP-programmable solution for USB-enabled embedded designs where field re-programmability is not required.
Key differentiating features include native USB 1.1 Low-Speed device support, 24 MHz maximum clock (4 MHz instruction rate from a 4:1 internal divider), 22 digital I/O pins, 5 channels of 8-bit ADC, and an integrated USART. The windowed CerDip package allows UV erasure of the EPROM, which makes the JW suffix particularly suited for prototyping and pre-production engineering rather than high-volume manufacturing.
The PIC16C745 uses a Harvard RISC architecture with separate program and data buses, plus a 14-bit instruction word. This architecture yields deterministic interrupt latency and single-cycle execution for most instructions, which simplifies real-time control firmware. The on-chip peripherals are mapped into the same linear data memory space, with special-function registers (SFRs) controlling the USB SIE, ADC, USART, and timers.
Typical applications include USB Human Interface Devices (HID) such as keyboards, mice, and game controllers, low-speed USB peripherals, industrial control front-ends, and educational/professional development platforms where the windowed package supports iterative firmware iteration. The 5-channel 8-bit ADC supports simple analog sensor acquisition.
Designers should note that the JW (CerDip windowed) variant is intended for development; production runs should migrate to the OT or SO/SS plastic packages. USB bus-powered designs must observe the 100 mA / 500 mA USB 1.1 power-budget rules and provide proper D+/D- series resistors and ESD protection.
直接替換替代品，適用於 PIC16C745/JW — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： PIC16C745/JW （相同外形與佔位） — 差異在於 Operating Temperature, Package, I/O Pins, Program Memory Type, Mounting Type.
PIC16C745-I/JW
✅ 直接替換📋 參考替代品（不在目錄中）
PIC16C765/JW
✅ 直接替換📋 參考替代品（不在目錄中）
PIC16C765-I/JW
✅ 直接替換📋 參考替代品（不在目錄中）
PIC16C745/JW
✅ 直接替換聯絡詢價
查看資料表 →PIC16C72/JW
✅ 直接替換聯絡詢價
查看資料表 →PIC16C717/JW
✅ 直接替換聯絡詢價
查看資料表 →PIC16C715/JW
✅ 直接替換聯絡詢價
查看資料表 →PIC16C745/JW 最大額定值與電氣特性
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Instruction Set | 35 single-word instructions, 14-bit wide |
| Program Memory | 14 KB (8K x 14) EPROM, UV-erasable |
| Data RAM | 256 bytes |
| 最大時脈頻率 | 24 MHz (4 MHz instruction rate) |
| Instruction Execution Time | 167 ns (at 24 MHz) |
| I/O Pins | 22 |
| ADC | 5 channels x 8-bit |
| USB | USB 1.1 Low-Speed device, certified |
| Serial Interface | USART (SCI) |
| Timers | 3 (Timer0, Timer1, Timer2) |
| 封裝 | 28-pin Ceramic DIP windowed (CerDip, JW) |
| 安裝類型 | Through-Hole |
| Program Memory Technology | OTP / UV-EPROM (windowed) |
| 工作溫度 | -40C to +85C (industrial) |
PIC16C745/JW 腳位配置
| 腳位 1 | MCLR/VPP — Master Clear (reset) / Programming voltage input |
| 腳位 2 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| 腳位 3 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| 腳位 4 | RA2/AN2 — Port A bit 2 / Analog input 2 |
| 腳位 5 | RA3/AN3/VREF — Port A bit 3 / Analog input 3 / ADC reference |
| 腳位 6 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| 腳位 7 | RA5/AN4/SS — Port A bit 5 / Analog input 4 / SPI Slave Select |
| 腳位 8 | VSS — Ground reference |
| 腳位 9 | OSC1/CLKIN — Oscillator input / external clock input |
| 腳位 10 | OSC2/CLKOUT — Oscillator output / clock output |
| 腳位 11 | RC0 — Port C bit 0 |
| 腳位 12 | RC1 — Port C bit 1 |
| 腳位 13 | RC2/CCP1 — Port C bit 2 / Capture-Compare-PWM 1 |
| 腳位 14 | RC3 — Port C bit 3 |
| 腳位 15 | RC4 — Port C bit 4 |
| 腳位 16 | RC5 — Port C bit 5 |
| 腳位 17 | RC6/TX/CK — Port C bit 6 / USART TX / clock |
| 腳位 18 | RC7/RX/DT — Port C bit 7 / USART RX / data |
| 腳位 19 | VSS — Ground reference |
| 腳位 20 | VDD — Positive supply voltage |
| 腳位 21 | RB0/INT — Port B bit 0 / external interrupt |
| 腳位 22 | RB1 — Port B bit 1 |
| 腳位 23 | RB2 — Port B bit 2 |
| 腳位 24 | RB3 — Port B bit 3 |
| 腳位 25 | RB4 — Port B bit 4 |
| 腳位 26 | RB5 — Port B bit 5 |
| 腳位 27 | RB6 — Port B bit 6 |
| 腳位 28 | RB7 — Port B bit 7 |
典型應用
PIC16C745/JW 適用於 6 應用s: USB HID Keyboard / Mouse, USB Low-Speed Industrial Peripheral, Educational Microcontroller Development Platform, USB Custom Vendor-Class Device, Legacy Maintenance and Spare-Part Replacement, USB Bootloader / Firmware Development Host.
USB HID Keyboard / Mouse
The PIC16C745's certified USB 1.1 Low-Speed SIE and 14 KB EPROM make it well suited for USB HID-class keyboards, mice, and game controllers. The integrated SIE eliminates an external USB transceiver for Low-Speed (1.5 Mbps) operation; combined with 256 bytes of RAM and 22 I/O pins, designers can implement scan-matrix debouncing, HID report descriptors, and basic macro firmware without external logic. The /JW windowed CerDip package allows iterative firmware updates via UV erasure during development, and the 24 MHz clock (4 MHz instruction rate) keeps interrupt latency deterministic for keyboard polling. Typical circuit: PIC16C745/JW with 24 MHz crystal, D+/D- lines to USB connector through 15 ohm series resistors, plus ESD protection on VBUS and data lines.
推薦
USB Low-Speed Industrial Peripheral
The PIC16C745's 5-channel 8-bit ADC, 22 I/O pins, and USB 1.1 Low-Speed interface enable cost-effective industrial peripherals such as USB temperature loggers, simple sensor interfaces, and lab instrumentation front-ends. The integrated ADC samples at a rate sufficient for slow analog signals (thermistors, photocells, potentiometers), while the USART (SCI) provides an optional RS-232 link for legacy equipment. The 14 KB EPROM fits small state machines and command parsers; the JW windowed package suits pre-production firmware bring-up. Power-budget considerations follow USB 1.1 rules: 100 mA in Low-power mode and 500 mA in High-power mode with proper enumeration.
推薦
Educational Microcontroller Development Platform
The PIC16C745/JW is widely used in university and embedded-systems courses because the windowed CerDip package allows UV erasure and re-programming of the EPROM for repeated lab cycles. The 35-instruction RISC architecture is approachable for teaching assembly fundamentals, while the integrated USB SIE provides a real-world I/O protocol for student projects. The 28-pin DIP form factor is breadboard-friendly, and the 14 KB EPROM supports complete class projects including USB HID stacks, ADC exercises, and PWM demos. The PIC16C745's instruction set is a superset of the PIC16C7X family, simplifying migration to modern PIC16F1 and PIC18 families.
推薦
USB Custom Vendor-Class Device
For simple USB vendor-class peripherals that do not need full-speed USB, the PIC16C745/JW provides a certified Low-Speed SIE, sufficient EPROM for vendor-class descriptors and basic data transfer firmware, and 22 I/O pins for peripheral-side control. Examples include custom USB test equipment, low-rate data acquisition pods, and proprietary configuration tools. The 24 MHz clock and 167 ns instruction cycle keep latency predictable, while the integrated ADC handles analog sampling without external components. The windowed CerDip package enables rapid firmware iteration during product development.
推薦
Legacy Maintenance and Spare-Part Replacement
Because the PIC16C745/JW is obsolete but still in service, it is often required for legacy equipment maintenance in industrial, medical, and aerospace systems designed in the late 1990s and 2000s. The windowed CerDip package matches the through-hole footprints of these legacy boards, allowing direct socket replacement without PCB rework. Authorized distributors maintain limited stock for such maintenance scenarios; pricing reflects the obsolete-part premium. Where possible, engineers are encouraged to redesign around the flash-based PIC16F745 to eliminate future obsolescence risk.
推薦
USB Bootloader / Firmware Development Host
The PIC16C745/JW windowed CerDip package and certified USB 1.1 Low-Speed SIE make it a convenient target for firmware development hosts that need to prototype USB device stacks, descriptor layouts, and class drivers without locking in OTP programming. The 14 KB of EPROM holds full HID or CDC stacks plus bootloader glue; 256 bytes of RAM supports stack frames and descriptor buffers. Engineers can iterate firmware by erasing the device under a UV lamp and re-programming in an EPROM programmer. This is particularly useful for early-stage USB stack bring-up, where multiple debug cycles are required.
推薦
推薦產品摘要
工程參考資料，適用於 PIC16C745/JW — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | PIC16C745-I/JW | PIC16C765/JW | PIC16C765-I/JW | PIC16C72/JW | PIC16C717/JW | PIC16C715/JW |
|---|---|---|---|---|---|---|---|
| Package | 28-CerDip windowed (JW) | 28-CerDip windowed (JW) - same | 28-CerDip windowed (JW) - same | 28-CerDip windowed (JW) - same | 28-CerDip windowed (JW) - same | 28-CerDip windowed (JW) - same | 28-CerDip windowed (JW) - same |
| Brand | Microchip Technology | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same |
| Program Memory | 14 KB EPROM | 14 KB EPROM - same | 28 KB EPROM (+100%) | 28 KB EPROM (+100%) | 2 KB EPROM (-86%) | 16 KB EPROM (+14%) | 14 KB EPROM - same |
| Data RAM | 256 B | 256 B - same | 768 B (+200%) | 768 B (+200%) | 128 B (-50%) | 256 B - same | 256 B - same |
| USB Support | USB 1.1 Low-Speed | USB 1.1 Low-Speed - same | USB 1.1 Low-Speed - same | USB 1.1 Low-Speed - same | None | None | None |
| ADC Channels | 5 x 8-bit | 5 x 8-bit - same | 5 x 8-bit - same | 5 x 8-bit - same | 5 x 8-bit - same | 6 x 10-bit | None |
| Max Clock | 24 MHz | 24 MHz - same | 24 MHz - same | 24 MHz - same | 20 MHz (-17%) | 20 MHz (-17%) | 20 MHz (-17%) |
| I/O Pins | 22 | 22 - same | 22 - same | 22 - same | 22 - same | 22 - same | 22 - same |
| Operating Temperature | 0C to +70C | -40C to +85C (industrial) | 0C to +70C | -40C to +85C (industrial) | 0C to +70C | 0C to +70C | 0C to +70C |
主要差異化特點
- Certified USB 1.1 Low-Speed SIE integrated on-chip (對比PIC16C72/JW)
- Larger program and data memory than baseline mid-range (對比PIC16C715/JW)
- Higher 24 MHz clock vs 20 MHz in legacy parts (對比PIC16C717/JW)
設計說明
The PIC16C745 operates from 4.0V to 6.0V (typical 5V) VDD. For USB bus-powered designs, derive the MCU supply from VBUS through a low-dropout regulator such as the MCP1700 with proper decoupling (100 nF + 10 uF bulk) on the VDD pin. USB Low-Speed devices are limited to 100 mA without enumeration; ensure firmware does not exceed this budget until configured for 500 mA High-power mode.
Place the 24 MHz crystal and load capacitors within 5 mm of the OSC1/OSC2 pins to minimize parasitic capacitance and ensure stable oscillation. Route the D+ and D- traces as a 90-ohm differential pair (per USB 1.1 spec) directly to the USB connector, keeping the traces short and away from switching regulator or oscillator nets. Add 15-ohm series resistors on D+ and D- close to the MCU side to suppress reflections.
The /JW windowed CerDip package is for development only - production runs must migrate to OT (OTP windowless CerDip) or SO/SS plastic packages to protect program memory from UV erasure by ambient light. Additionally, the PIC16C745 USB SIE requires the internal 24 MHz clock; operating below 24 MHz causes USB compliance failures. Firmware developers must configure the PLL and USB clock-prescaler correctly per the datasheet USB chapter.
For USB Low-Speed signal integrity, the D+ line requires a 1.5 kohm pull-up to 3.3V (not 5V) to indicate Low-Speed device presence to the host. The D- line has no pull-up. Add ESD protection (such as USBLC6-2SC6) on the USB connector data lines to meet IEC 61000-4-2 ESD ratings. Keep the pull-up resistor within 50 mm of the D+ pin and route the pull-up trace to a clean 3.3V rail.
合規資訊
CerDip windowed packages are typically NOT RoHS-compliant due to leaded glass seals; production parts use lead-free plastic. AEC-Q100 not applicable - this is a commercial/industrial grade MCU. Compliance data not explicitly stated in verified web data; mark as unknown.
