PIC17C42A-33I/L - 8-Bit 33MHz OTP MCU, 4KB | Microchip
MPN: PIC17C42A-33I/L ✗ Cuối đờiPIC17C42A-33I/L Tóm tắt
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory, working RAM, and peripheral interfaces onto one piece of silicon. Within the broader semiconductor taxonomy, a microcontroller is a sub-class of microprocessor that targets embedded control rather than general-purpose computing; the 8-bit class, to which the PIC17C42A belongs, occupies the entry-to-mid level of performance and emphasizes deterministic instruction timing, low pin count, and cost-sensitive integration. The PIC17C4X specifically extended Microchip's baseline PIC16C5X/PIC16CXX architecture with a wider instruction word and a higher 33 MHz clock ceiling.
Key features include an 8.25 MIPS peak throughput, 58 single-word instructions for fast code development, hardware multiply and divide support, a four-channel 8-bit ADC, dual analog comparators, three timer/counter modules (Timer0/Timer1/Timer2), a Universal Synchronous Asynchronous Receiver-Transmitter (USART), and a Capture/Compare/PWM (CCP) peripheral. The 16-bit-wide instruction word and 8-bit data path give the family a RISC-flavored execution model while remaining source-compatible with the PIC16 midrange instruction set.
The PIC17C42A is implemented in CMOS technology with an EPROM/OTP program cell, allowing one-time programmable code storage in production. Its 12-bit-wide instruction bus, 8-bit data ALU, and Harvard architecture let the CPU fetch instructions and data in parallel, which is why most instructions complete in a single 121 ns cycle. Program branches and table reads/writes extend to two cycles, an architectural detail engineers use when bounding interrupt latency.
Typical applications include industrial control subsystems, motor drive signal conditioning, instrumentation front ends, white-goods and appliance controllers, and legacy embedded designs where the PIC17C4X architecture is already in use. The wide temperature grade and the through-hole-friendly PLCC-44 package make it especially suitable for factory-floor equipment and field-replaceable modules. Microchip's own product page recommends migrating to the PIC18F4220 for new designs, since the PIC17C42A is no longer in active production.
When designing with this part, plan for a 5V supply and ensure the external oscillator is matched to the 33 MHz maximum clock. Decouple VDD with 0.1 uF ceramic capacitors placed within 5 mm of each power pin, and reserve the MCLR pin for a proper reset network. Because the part is OTP, firmware must be fully validated before programming - there is no in-circuit reprogramming.
This page synthesizes distributor stock signals, current pricing tiers, a curated set of drop-in compatible alternatives, and practical design notes that go beyond the manufacturer datasheet, giving engineers and procurement teams a single decision-ready reference.
Bộ thay thế dễ dàng lắp đặt cho PIC17C42A-33I/L — 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 PIC17C42A-33I/L (cùng hình factor và footprint) — khác nhau ở Program Memory Type, Package, Core Architecture, Program Memory Size, Oscillator Type.
PIC17C42A-33E/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC17C42A-33I/P
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC17C43-33I/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC17C42A-33E/PT
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC17C42A-33I/L Tỷ lệ tối đa & tính chất điện
| Core | PIC17C, 8-bit |
| Program Memory Type | EPROM/OTP |
| Program Memory Size | 4 KB (2K x 16) |
| RAM Size | 232 x 8 bytes |
| Tần số xung maksimum | 33 MHz |
| Instruction Cycle Time | 121 ns (single cycle) |
| Throughput | 8.25 MIPS |
| Instruction Set Size | 58 single-word instructions |
| Number of I/O Pins | 33 |
| Hộp | 44-LCC (J-Lead, 16.59 x 16.59 mm) |
| Oscillator Type | External |
| Khoảng nhiệt độ hoạt động | -40 C to +85 C (Industrial) |
| Timers | 3 (Timer0/Timer1/Timer2) |
| USART | 1 |
| Capture/Compare/PWM | Yes (CCP) |
| Temperature Grade | Industrial |
| Terminal Form | J-Bend (PLCC) |
| Package Code | QCCJ |
Cấu hình chân PIC17C42A-33I/L
| Chân 1 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Chân 2 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Chân 3 | RA2/AN2 — PORTA bit 2 / Analog input 2 |
| Chân 4 | RA3/AN3 — PORTA bit 3 / Analog input 3 |
| Chân 5 | RA4 — PORTA bit 4 (digital only) |
| Chân 6 | RA5 — PORTA bit 5 (digital only) |
| Chân 7 | RA6 — PORTA bit 6 (digital only) |
| Chân 8 | RA7 — PORTA bit 7 (digital only) |
| Chân 9 | OSC1 — External oscillator input |
| Chân 10 | OSC2 — External oscillator output |
| Chân 11 | RC0 — PORTC bit 0 |
| Chân 12 | RC1 — PORTC bit 1 |
| Chân 13 | RC2 — PORTC bit 2 |
| Chân 14 | RC3 — PORTC bit 3 |
| Chân 15 | RC4 — PORTC bit 4 |
| Chân 16 | RC5 — PORTC bit 5 |
| Chân 17 | RC6 — PORTC bit 6 |
| Chân 18 | RC7 — PORTC bit 7 |
| Chân 19 | VSS — Ground reference |
| Chân 20 | VDD — Positive supply (typical 5 V) |
| Chân 21 | RB0/INT — PORTB bit 0 / External interrupt |
| Chân 22 | RB1 — PORTB bit 1 |
| Chân 23 | RB2 — PORTB bit 2 |
| Chân 24 | RB3 — PORTB bit 3 |
| Chân 25 | RB4 — PORTB bit 4 |
| Chân 26 | RB5 — PORTB bit 5 |
| Chân 27 | RB6 — PORTB bit 6 |
| Chân 28 | RB7 — PORTB bit 7 |
| Chân 29 | MCLR — Master Clear (reset, active low) |
| Chân 30 | RD0 — PORTD bit 0 |
| Chân 31 | RD1 — PORTD bit 1 |
| Chân 32 | RD2 — PORTD bit 2 |
| Chân 33 | RD3 — PORTD bit 3 |
| Chân 34 | RD4 — PORTD bit 4 |
| Chân 35 | RD5 — PORTD bit 5 |
| Chân 36 | RD6 — PORTD bit 6 |
| Chân 37 | RD7 — PORTD bit 7 |
| Chân 38 | RE0 — PORTE bit 0 |
| Chân 39 | RE1 — PORTE bit 1 |
| Chân 40 | RE2 — PORTE bit 2 |
| Chân 41 | T0CKI — Timer0 external clock input |
| Chân 42 | VSS — Ground reference (secondary) |
| Chân 43 | VDD — Positive supply (secondary) |
| Chân 44 | NC — Not connected (per datasheet) |
Ứng dụng tiêu biểu
PIC17C42A-33I/L phù hợp cho 6 Áp dụngs: Industrial Motor Drive Control Loops, White Goods and Appliance Controllers, Instrumentation and Test Equipment Front Ends, Legacy Embedded Communication Gateways, Automotive Aftermarket and Hobby Modules, Field-Replaceable Industrial Modules.
Industrial Motor Drive Control Loops
The PIC17C42A-33I/L is well suited to industrial motor drive control loops where deterministic 121 ns instruction timing and 8.25 MIPS throughput matter. Its 33 MHz maximum clock and Harvard architecture let a fixed-cycle PI or PID loop close every PWM period, while the on-chip Capture/Compare/PWM peripheral directly drives the gate driver timing. Three timer/counter modules (Timer0/Timer1/Timer2) plus the USART allow simultaneous speed sampling, current-sense ADC reads, and host telemetry over RS-232/RS-485 without an external peripheral chip. The 44-PLCC J-lead package also supports through-hole sockets, which simplifies factory-floor maintenance on legacy drives.
Được đề xuất
White Goods and Appliance Controllers
The PIC17C42A-33I/L has historically been used in white goods and appliance controllers where its OTP program memory, 33 I/O pins, and industrial -40C to +85C temperature grade meet long-life production runs. The four-channel 8-bit ADC reads thermistor, water-level, and door-switch sensors; the dual analog comparators handle zero-crossing detection for triac-driven heater elements. Because the part is OTP, the firmware is locked at production time, which protects manufacturers from unauthorized code modifications. Its 5 V CMOS core and external oscillator make it straightforward to retrofit into existing appliance platforms with proven reliability.
Được đề xuất
Instrumentation and Test Equipment Front Ends
The PIC17C42A-33I/L's 8.25 MIPS throughput and on-chip 8-bit ADC make it a workable controller for instrumentation and test equipment front ends that demand deterministic data acquisition. Its USART connects to a host PC or display for command and data logging, while the CCP peripheral handles pulse-width or frequency measurements. The PIC17C instruction set - 58 single-word instructions - keeps firmware compact within the 4 KB OTP budget, leaving room for calibration tables and command parsers. The 44-PLCC J-lead package is well suited to benchtop or rack-mount instrument boards where field-replaceable sockets are valued.
Được đề xuất
Legacy Embedded Communication Gateways
The PIC17C42A-33I/L can serve as a legacy embedded communication gateway between industrial sensors and a host controller, using its on-chip USART plus software-driven bit-banging for additional serial channels. Its 33 MHz clock and 232 bytes of RAM are sufficient to buffer packets while a higher-level host polls slowly over RS-232 or RS-485. The OTP memory model locks the gateway firmware at production time, which prevents in-field tampering with the protocol stack. The 33 digital I/O pins allow direct interfacing to LED indicators, DIP switches, and discrete control lines without an external I/O expander.
Được đề xuất
Automotive Aftermarket and Hobby Modules
Although not AEC-Q100 qualified, the PIC17C42A-33I/L remains common in automotive aftermarket and hobby modules where its PIC17C architecture is already established. Its 33 MHz performance and 4 KB OTP allow fixed-cycle timing of fuel injection simulators, gauge drivers, and engine-control demonstrators, while the 44-PLCC package supports easy prototyping on socketed boards. Designers should observe the industrial -40C to +85C temperature grade and avoid under-hood environments that exceed the rating. For new automotive designs, Microchip's PIC18F4220 with flash memory and an active lifecycle is the recommended path.
Được đề xuất
Field-Replaceable Industrial Modules
The PIC17C42A-33I/L is widely deployed in field-replaceable industrial modules - PLC-style I/O cards, sensor signal conditioners, and process control boards - where its 44-PLCC J-lead package and OTP memory are specified by qualification. The J-lead PLCC accepts both SMT soldering and a through-hole socket, which simplifies field swap without board rework. The 33 MHz clock and 4 KB OTP memory provide enough headroom for protocol stacks (Modbus RTU over USART), calibration tables, and diagnostic routines. Because the family is obsolete, integrators are advised to qualify a second source such as PIC17C43-33I/L for new deployments.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC17C42A-33I/L — 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 | PIC17C42A-33E/L | PIC17C43-33I/L | PIC17C42A-33E/PT | PIC17C42A-33I/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-TQFP - different package | 40-PDIP - different package |
| Maximum Clock Frequency | 33 MHz | 33 MHz | 33 MHz | 33 MHz | 33 MHz |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete |
Bảo phân biệt quan trọng
- Same PIC17C4X family instruction set with industrial temperature grade (vsPIC17C42A-33E/L)
- Larger code space within the same PIC17C instruction set (vsPIC17C42A-33I/P (40-PDIP variant))
- 44-PLCC J-lead package supports through-hole sockets for field service (vsPIC17C42A-33E/PT (44-TQFP))
Ghi chú thiết kế
Decouple every VDD/VSS pair with a 0.1 uF ceramic capacitor placed within 5 mm of the IC pin, and add a 10 uF bulk capacitor near the supply entry point. The PIC17C42A-33I/L is a 5 V CMOS part and the supply trace inductance must be kept low so that high-current I/O transitions do not collapse VDD and trigger spurious resets via MCLR. Use a star-ground topology tying VSS pins together at the chip rather than a daisy-chained ground.
The PIC17C42A-33I/L is OTP (one-time programmable) - once a device is programmed it cannot be erased or rewritten. Validate firmware on a windowed PIC17C42A prototype or PIC18F4220 equivalent before committing to production programming, because field firmware updates are impossible. Also note the part is in Microchip's obsolete lifecycle; qualify a second source such as PIC17C43-33I/L or migrate to PIC18F4220 for new designs.
The 44-PLCC J-lead package has a 1.27 mm pitch with J-bend terminals; reserve space for either SMT soldering or a through-hole PLCC socket so that field-replaceable units can be swapped without board rework. Keep the OSC1/OSC2 trace lengths under 10 mm and surround them with a ground pour to suppress oscillator noise. Route the MCLR reset line away from high-current switching traces and place the MCLR pull-up resistor close to the IC pin.
Thông tin tuân thủ
RoHS/REACH/lead-free status not present in the verified distributor data; the part is in Microchip's obsolete lifecycle so most modern compliance declarations are not actively maintained. AEC-Q100 is not applicable (this is an industrial-grade legacy MCU).
