PIC16C74A-04I/PQ - 8-Bit 4MHz MCU 7KB OTP 44-MQFP | Microchip
MPN: PIC16C74A-04I/PQ ✗ סוף ייצורPIC16C74A-04I/PQ סקירה
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program and data memory, I/O peripherals, and often timers, communication interfaces, and ADCs onto one IC. MCUs sit within the embedded computing hierarchy as programmable logic devices, bridging discrete logic ICs on the low end and full microprocessor-based systems on the high end. The PIC16C74A belongs to the OTP-programmable, ROM-based branch of the PIC family, meaning the program memory can be written only once - suitable for low-cost, high-volume production where code stability is final.
Key features of the PIC16C74A include three timer/counters (Timer0, Timer1, Timer2), a Universal Synchronous/Asynchronous Receiver-Transmitter (USART) for serial communication, a Master Synchronous Serial Port (SSP) supporting SPI and I2C, an 8-channel 8-bit A/D converter, a watchdog timer with its own on-chip RC oscillator, and brown-out reset / power-on reset circuitry. The industrial temperature grade (-40C to +85C) is denoted by the "I" suffix, while "04" specifies the 4 MHz maximum operating frequency and "/PQ" indicates the 44-pin MQFP package supplied in tray.
Architecturally, the PIC16C74A uses a Harvard architecture with separate program and data buses, a 14-bit wide program memory bus, and a two-stage pipeline for deterministic single-cycle instruction execution. The CMOS process yields very low power consumption (typically < 2 mA at 5 V, 4 MHz) and full static operation, allowing the clock to be stopped without losing register state. Power management is supported via Sleep mode with wake-up on interrupt or watchdog timeout.
Typical applications include industrial control systems, automotive body and chassis electronics, appliance controllers, security and alarm panels, and instrumentation requiring on-chip A/D conversion. The combination of OTP memory, integrated analog, and a robust USART makes the PIC16C74A a cost-effective solution for fixed-code, mid-volume embedded products.
When designing with the PIC16C74A-04I/PQ, note that Microchip recommends PIC16F74 as the recommended modern replacement - it is flash-based, re-programmable, and offers the same peripheral set in a pin-compatible or near-pin-compatible package, easing migration for new designs. The OTP nature of the PIC16C74A means firmware cannot be field-updated; provision for bootloader or external EEPROM is essential if in-system updates are required.
This page consolidates distributor pricing, a cross-brand drop-in alternatives matrix, and design notes compiled from the manufacturer datasheet - a synthesis not found on any single distributor or datasheet page.
חלופות תחליף ישיר עבור PIC16C74A-04I/PQ — אותו מארז, תואם פין-לפין. חלקים במארז שונה הדורשים עיבוד מחדש של ה-PCB אינם נכללים.
וריאנטים בסדרה זו
דגמים מאותה סדרה התואמים Drop-in עם PIC16C74A-04I/PQ (אותו גורם צורה וטביעת רגל) — שונים ב Package, Operating Temperature, Core Architecture, Timers, ADC.
PIC16C74A-04/PQ
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC16C74A-04I/P
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC16C74A-04I/PT
✅ Drop-In ⚠️ מפרטים לא מאומתיםצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC16C74A-20I/PQ
✅ Drop-In ⚠️ מפרטים לא מאומתיםצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC16C74A-10I/PQ
✅ Drop-In ⚠️ מפרטים לא מאומתיםצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC16C74A-04I/PQ דירוגים מרביים ומאפיינים חשמליים
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Family | PIC16C7X mid-range |
| Program Memory Type | OTP (One-Time-Programmable) EPROM |
| Program Memory Size | 7 KB (4K x 14) |
| RAM Size | 192 bytes |
| Data EEPROM | 0 bytes (none on-chip) |
| תדר שעון מקסימלי | 4 MHz |
| Instruction Set | 35 instructions, 14-bit wide |
| Supply Voltage (VDD) | 4.0 V to 6.0 V |
| I/O Pins | 33 digital I/O |
| A/D Converter | 8 channels, 8-bit resolution |
| Timers | Timer0, Timer1, Timer2 (3 total) |
| Serial Interfaces | USART (SCI), SSP (SPI/I2C) |
| טמפרטורת פעולה | -40 C to +85 C (Industrial) |
| מארז | 44-pin MQFP (10x10 mm), Tray |
| סוג הרכבה | Surface Mount |
| Recommended Replacement | PIC16F74 (flash-based, modern equivalent) |
תצורת פינים של PIC16C74A-04I/PQ
| פין 1 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| פין 2 | RA0/AN0 — PORTA bit 0 / Analog input channel 0 |
| פין 3 | RA1/AN1 — PORTA bit 1 / Analog input channel 1 |
| פין 4 | RA2/AN2 — PORTA bit 2 / Analog input channel 2 |
| פין 5 | RA3/AN3/VREF — PORTA bit 3 / Analog input channel 3 / A/D reference |
| פין 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| פין 7 | RA5/AN4/SS — PORTA bit 5 / Analog input channel 4 / SSP slave select |
| פין 8 | RE0/RD/AN5 — PORTE bit 0 / Read control for parallel slave port / Analog input 5 |
| פין 9 | RE1/WR/AN6 — PORTE bit 1 / Write control for parallel slave port / Analog input 6 |
| פין 10 | RE2/CS/AN7 — PORTE bit 2 / Chip select for parallel slave port / Analog input 7 |
| פין 11 | VDD — Positive supply voltage |
| פין 12 | VSS — Ground reference |
| פין 13 | OSC2/CLKOUT — Oscillator crystal output / clock output |
| פין 14 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| פין 15 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / Capture/Compare/PWM 2 |
| פין 16 | RC2/CCP1 — PORTC bit 2 / Capture/Compare/PWM 1 |
| פין 17 | RC3/SCK/SCL — PORTC bit 3 / SSP serial clock (SPI/I2C) |
| פין 18 | RC4/SDI/SDA — PORTC bit 4 / SSP serial data in (SPI) / data (I2C) |
| פין 19 | RC5/SDO — PORTC bit 5 / SSP serial data out (SPI) |
| פין 20 | RC6/TX/CK — PORTC bit 6 / USART transmit / USART clock |
| פין 21 | RC7/RX/DT — PORTC bit 7 / USART receive / USART data |
| פין 22 | RD0/PSP0 — PORTD bit 0 / Parallel slave port bit 0 |
| פין 23 | RD1/PSP1 — PORTD bit 1 / Parallel slave port bit 1 |
| פין 24 | RD2/PSP2 — PORTD bit 2 / Parallel slave port bit 2 |
| פין 25 | RD3/PSP3 — PORTD bit 3 / Parallel slave port bit 3 |
| פין 26 | RD4/PSP4 — PORTD bit 4 / Parallel slave port bit 4 |
| פין 27 | RD5/PSP5 — PORTD bit 5 / Parallel slave port bit 5 |
| פין 28 | RD6/PSP6 — PORTD bit 6 / Parallel slave port bit 6 |
| פין 29 | RD7/PSP7 — PORTD bit 7 / Parallel slave port bit 7 |
| פין 30 | VSS — Ground reference |
| פין 31 | RB0/INT — PORTB bit 0 / External interrupt input |
| פין 32 | RB1 — PORTB bit 1 |
| פין 33 | RB2 — PORTB bit 2 |
| פין 34 | RB3 — PORTB bit 3 |
| פין 35 | RB4 — PORTB bit 4 |
| פין 36 | RB5 — PORTB bit 5 |
| פין 37 | RB6/PGC — PORTB bit 6 / In-circuit debugger / ICSP clock |
| פין 38 | RB7/PGD — PORTB bit 7 / In-circuit debugger / ICSP data |
| פין 39 | MCLR/VPP — Master clear reset input / programming voltage |
| פין 40 | VDD — Positive supply voltage |
| פין 41 | NC — Not connected (no internal bond - leave open per datasheet) |
| פין 42 | NC — Not connected (no internal bond - leave open per datasheet) |
| פין 43 | NC — Not connected (no internal bond - leave open per datasheet) |
| פין 44 | NC — Not connected (no internal bond - leave open per datasheet) |
יישומים טיפוסיים
PIC16C74A-04I/PQ מתאים עבור 7 יישוםs: Industrial Control Systems, Appliance Control Boards, Automotive Body Electronics, Security and Alarm Panels, Instrumentation and Data Acquisition Front-Ends, HVAC Control Modules, Power Supply Monitoring and Sequencing.
Industrial Control Systems
The PIC16C74A-04I/PQ fits industrial control designs that demand deterministic 8-bit processing, an integrated 8-channel 8-bit A/D converter for sensor reading, and USART connectivity to supervisory PLCs or HMIs. At 4 MHz and 5 V VDD, the MCU executes most instructions in a single 250 ns cycle, providing predictable loop times for PID-style control loops over temperature, pressure, or flow sensors. The 33 digital I/O lines comfortably drive relay drivers, optocouplers, and keypad/display interfaces. Its industrial -40C to +85C temperature grade supports factory-floor deployments without additional thermal hardening.
מומלץ
Appliance Control Boards
The PIC16C74A-04I/PQ is well suited to appliance control boards (washing machines, dishwashers, microwave ovens) where the OTP memory locks the firmware at production and the integrated A/D reads thermistors, water-level sensors, and motor-current shunts. Its 7 KB program memory accommodates state-machine firmware for cycle control, while the SSP in I2C mode interfaces with character LCDs or EEPROMs for user settings. The 33 I/O lines handle keypads, seven-segment displays, triac drivers, and buzzer feedback. Industrial temperature grade accommodates the under-cabinet thermal environment.
מומלץ
Automotive Body Electronics
The PIC16C74A-04I/PQ can power non-safety-critical automotive body electronics such as interior lighting controllers, seat-position memory modules, and aftermarket gauge clusters. The on-chip 8-bit A/D reads potentiometers for analog trim inputs, the USART communicates with body-control modules over LIN-like protocols, and the 33 I/O lines drive LED arrays and H-bridge motor drivers. While not AEC-Q100 qualified, its industrial temperature grade and CMOS robustness suit cabin-mounted applications. For under-hood or safety-critical use, an AEC-Q100 part should be specified instead.
מומלץ
Security and Alarm Panels
The PIC16C74A-04I/PQ serves security alarm control panels where its USART dials out to central stations via modem, the A/D monitors backup-battery voltage and PIR sensor levels, and the SSP drives I2C EEPROMs for event-log retention. With 7 KB of OTP, fixed code holds the alarm logic, zone definitions, and communication protocols. Watchdog timer and brown-out reset enhance field reliability against brown-outs and code runaway - both critical in 24/7 unattended operation.
מומלץ
Instrumentation and Data Acquisition Front-Ends
The PIC16C74A-04I/PQ provides a compact, low-cost 8-channel data-acquisition front-end for bench instruments and process monitors. The integrated 8-bit A/D samples analog inputs at rates determined by acquisition time and clock, while the USART streams digitized data to a host PC or display. With 192 bytes of RAM, sample buffering is shallow, but the part suits slow-changing signals like temperature, pressure, and position. The 4 MHz clock supports a deterministic acquisition loop and leaves CPU headroom for averaging and scaling.
מומלץ
HVAC Control Modules
The PIC16C74A-04I/PQ is appropriate for HVAC control modules where multiple analog inputs (temperature sensors, humidity transducers, pressure switches) are scanned via the integrated 8-channel A/D, and triac drivers or relay coils are switched via 33 digital I/O lines. The 7 KB OTP memory stores the closed-loop control algorithm and user-mode logic, while the USART interfaces to a wall thermostat or building management system. Industrial temperature grade covers attic and mechanical-room installations.
מומלץ
Power Supply Monitoring and Sequencing
The PIC16C74A-04I/PQ can orchestrate multi-rail power-supply sequencing and monitoring in telecom and server equipment. Its A/D reads output voltages and current-sense amplifiers, the USART reports telemetry to a supervisory controller, and GPIO lines drive power-good signals and enable pins of downstream regulators. Brown-out reset and watchdog timer provide failsafe behavior against firmware lockup. The 4 MHz clock and 5 V supply are compatible with classic analog supply topologies.
מומלץ
סיכום מוצרים מומלצים
נתוני עזר הנדסיים עבור PIC16C74A-04I/PQ — השוואה, הנחיות תכנון ומידע על תאימות.
מדריך בחירה
השוואה עם חלופות
| פרמטר | מוצר זה | PIC16C74A-04/PQ | PIC16C74A-04I/P | PIC16C74A-04I/PT | PIC16C74A-20I/PQ | PIC16C74A-10I/PQ |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-MQFP (10x10) | 44-MQFP (10x10) - same | 40-PDIP - differs (TH vs SMD, 40 vs 44 pins) | 44-TQFP - differs in lead pitch | 44-MQFP (10x10) - same | 44-MQFP (10x10) - same |
| Program Memory | 7 KB OTP (4K x 14) | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz | 10 MHz |
| Temperature Grade | Industrial (-40C to +85C) | Commercial (0C to +70C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) |
| A/D Converter | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit |
| I/O Pins | 33 | 33 | 33 (40-pin DIP variant) | 33 | 33 | 33 |
| Supply Voltage | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 4.0 V to 6.0 V |
| Lifecycle Status | Obsolete (EOL) | Obsolete (EOL) | Obsolete (EOL) | Obsolete (EOL) | Obsolete (EOL) | Obsolete (EOL) |
מבדילים עיקריים
- Highest-clock variant available in same MQFP package (לעומתPIC16C74A-04/PQ)
- Through-hole drop-in variant for breadboard/prototype use (לעומתPIC16C74A-04I/P)
- Same die, different lead pitch for TQFP socket compatibility (לעומתPIC16C74A-04I/PT)
- Industrial temperature grade for harsh environments (לעומתPIC16C74A-04/PQ)
הערות תכנון
Estimated: at 5 V VDD and 4 MHz clock, the PIC16C74A typically draws < 2 mA active and < 1 uA in Sleep mode. Decouple VDD with a 0.1 uF ceramic capacitor placed within 5 mm of the VDD pin (pin 11 or pin 40), plus a bulk 10 uF tantalum or aluminum capacitor on the supply rail. Both VSS pins (12 and 30) must be connected to a low-impedance ground plane. The MCLR/VPP pin should be tied to VDD through a 10 kohm resistor with a 0.1 uF capacitor to VDD for proper reset behavior. In-circuit serial programming (ICSP) requires no isolation of the MCLR pull-up.
The PIC16C74A uses OTP (One-Time-Programmable) EPROM, meaning firmware cannot be erased or rewritten after programming. Do not use this part for prototyping or designs that may require firmware updates - select a Flash-based PIC16F74 or PIC16F877A instead. Configuration bits (fuses) must be set before code programming; omitting the watchdog timer enable bit can leave the system unprotected against firmware lockup. Brown-out reset should be enabled for any mains-powered application to prevent code execution at low VDD.
The 44-MQFP package has 0.8 mm lead pitch and 10x10 mm body - PCB land pattern must follow IPC-7351 nominal-density MQFP recommendations with at least 0.4 mm annular ring and 5 mil trace width. Place decoupling capacitors within 5 mm of every VDD/VSS pin pair, and route the oscillator traces (OSC1/OSC2) short and symmetric. Keep analog inputs (RA0-RA5, RE0-RE2) away from digital switching traces to minimize ADC crosstalk. The four NC pins (41-44) on this package must be left open per the datasheet - do not connect them to any net.
When using the on-chip ADC, place a 0.1 uF bypass capacitor adjacent to AVdd and AVss pins (RA0-RA5 share with analog functions). For high-impedance analog sources, use a source-follower buffer or sample-and-hold to avoid ADC sample-capacitor-induced droop. The parallel slave port (PORTD plus PORTE control lines) should be used only with short PCB traces (< 50 mm) to avoid bus contention and ringing at higher system speeds; for longer runs, external buffering is recommended.
מידע על תאימות
RoHS/REACH/lead-free status not explicitly stated in the verified web data for the PIC16C74A-04I/PQ. The PIC16C7X family predates widespread RoHS adoption; many lots were originally produced as SnPb-finished, though Microchip transitioned most products to lead-free finishes in the 2000s. AEC-Q100 not qualified - not suitable for automotive safety-critical applications without further qualification. Consult Microchip product compliance documentation for authoritative RoHS/REACH certificates.
