PIC16C745/JW - 8-Bit 24MHz USB MCU, 14KB EPROM, 28-CerDip | Microchip
MPN: PIC16C745/JW ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.2 | $162.00 |
| 100 | $13.85 | $1,385.00 |
| 500 | $11.4 | $5,700.00 |
| 1,000 | $9.95 | $9,950.00 |
PIC16C745/JW Overview
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.
Drop-in alternatives for PIC16C745/JW — 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 PIC16C745/JW (same form factor and footprint) — differing in Operating Temperature, Package, I/O Pins, Program Memory Type, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C745-I/JW
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C765/JW
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C765-I/JW
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C745/JW
✅ Drop-In✓ In Stock
$9.95 / Unit
View Datasheet →PIC16C72/JW
✅ Drop-In✓ In Stock
$17.8 / Unit
View Datasheet →PIC16C717/JW
✅ Drop-In✓ In Stock
$11.8 / Unit
View Datasheet →PIC16C715/JW
✅ Drop-In✓ In Stock
$9.75 / Unit
View Datasheet →PIC16C745/JW Maximum Ratings & Electrical Characteristics
| 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 |
| Maximum Clock Frequency | 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) |
| Package | 28-pin Ceramic DIP windowed (CerDip, JW) |
| Mounting Type | Through-Hole |
| Program Memory Technology | OTP / UV-EPROM (windowed) |
| Operating Temperature | -40C to +85C (industrial) |
PIC16C745/JW Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) / Programming voltage input |
| Pin 2 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2 — Port A bit 2 / Analog input 2 |
| Pin 5 | RA3/AN3/VREF — Port A bit 3 / Analog input 3 / ADC reference |
| Pin 6 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — Port A bit 5 / Analog input 4 / SPI Slave Select |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 10 | OSC2/CLKOUT — Oscillator output / clock output |
| Pin 11 | RC0 — Port C bit 0 |
| Pin 12 | RC1 — Port C bit 1 |
| Pin 13 | RC2/CCP1 — Port C bit 2 / Capture-Compare-PWM 1 |
| Pin 14 | RC3 — Port C bit 3 |
| Pin 15 | RC4 — Port C bit 4 |
| Pin 16 | RC5 — Port C bit 5 |
| Pin 17 | RC6/TX/CK — Port C bit 6 / USART TX / clock |
| Pin 18 | RC7/RX/DT — Port C bit 7 / USART RX / data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RB0/INT — Port B bit 0 / external interrupt |
| Pin 22 | RB1 — Port B bit 1 |
| Pin 23 | RB2 — Port B bit 2 |
| Pin 24 | RB3 — Port B bit 3 |
| Pin 25 | RB4 — Port B bit 4 |
| Pin 26 | RB5 — Port B bit 5 |
| Pin 27 | RB6 — Port B bit 6 |
| Pin 28 | RB7 — Port B bit 7 |
Typical Applications
PIC16C745/JW is suitable for 6 applications: 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.
Recommended
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.
Recommended
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.
Recommended
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.
Recommended
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.
Recommended
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.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C745/JW — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | 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 |
Key Differentiators
- Certified USB 1.1 Low-Speed SIE integrated on-chip (vs PIC16C72/JW)
- Larger program and data memory than baseline mid-range (vs PIC16C715/JW)
- Higher 24 MHz clock vs 20 MHz in legacy parts (vs PIC16C717/JW)
Design Notes
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.
Compliance Information
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.
