PIC16C74A-20E/P - 8-Bit 20MHz 7KB OTP MCU 40-PDIP | Microchip
MPN: PIC16C74A-20E/P ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.45 | $9.45 |
| 10 | $8.5 | $85.00 |
| 100 | $7.55 | $755.00 |
| 500 | $6.8 | $3,400.00 |
| 1,000 | $6.1 | $6,100.00 |
PIC16C74A-20E/P Overview
An 8-bit microcontroller is a single-chip computer with an 8-bit data bus and ALU that executes instructions one byte at a time. PIC mid-range microcontrollers sit between PIC baseline and PIC enhanced families in the Microchip taxonomy: PIC baseline -> PIC mid-range -> PIC enhanced -> dsPIC -> PIC32. The PIC16C7X family specifically targets applications requiring integrated analog and digital peripherals in a single device, bridging the gap between simple PIC16C5x baseline controllers and more powerful PIC17C parts.
Key features of the PIC16C74A-20E/P include a wide 4V to 6V operating range, an extended industrial temperature grade ("-E" suffix = -40C to +125C), 15 interrupt sources, a watchdog timer with its own on-chip RC oscillator, a programmable 8-bit prescaler, and power-saving SLEEP mode. The device uses a RISC architecture with only 35 single-word/single-cycle instructions, simplifying embedded firmware development and reducing code size for cost-OTP ROMs.
Architecturally, the PIC16C74A-20E/P employs a Harvard architecture with separate 14-bit program memory and 8-bit data memory buses, allowing instruction fetch and data access to occur simultaneously each clock cycle. This dual-bus design delivers near-1 MIPS per MHz throughput, while the OTP EPROM process technology enables rapid prototyping and low-volume production without the mask-programming tooling investment required by ROM-based PICs.
Typical applications for the PIC16C74A-20E/P include industrial process control systems, motor control and HVAC equipment, instrumentation and data acquisition modules, automotive body and chassis subsystems, security and alarm panels, and general-purpose embedded control where integrated A/D plus USART plus I/O eliminate the need for external peripherals. The 40-pin PDIP form factor is convenient for prototype through-hole assembly.
A key design consideration is the "/P" suffix designating 40-pin PDIP through-hole mounting versus the "/L" (PLCC) or "/PQ" (MQFP) variants; pin-compatible OTP replacements with the same -20 speed grade and -E temperature range are the primary drop-in options. Designers should also note that Microchip recommends migrating to the flash-based PIC16F74 for new designs since PIC16C OTP parts are legacy devices with limited long-term supply continuity.
This page synthesizes distributor stock and pricing data, same-package drop-in alternatives, application guidance, and design notes not consolidated on any single manufacturer or distributor page, giving engineers a single reference for evaluating the PIC16C74A-20E/P for both new designs and legacy maintenance.
Drop-in alternatives for PIC16C74A-20E/P — 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 PIC16C74A-20E/P (same form factor and footprint) — differing in Package, Core Architecture, Timers, Watchdog Timer, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F74-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C74A-20/PQ
✅ Drop-In✓ In Stock
$6.1 / Unit
View Datasheet →PIC16C74A-10E/P
✅ Drop-In✓ In Stock
$5.94 / Unit
View Datasheet →PIC16C74A-04I/P
✅ Drop-In✓ In Stock
$7.5 / Unit
View Datasheet →PIC16C74A-10/P
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →PIC16C74A-20E/P Maximum Ratings & Electrical Characteristics
| Product Family | PIC 16C Mid-Range |
| Core Architecture | 8-bit RISC (Harvard) |
| Instruction Set | 35 single-word instructions |
| Program Memory Type | OTP (One-Time-Programmable EPROM) |
| Program Memory Size | 7 KB (4K x 14 words) |
| RAM Size | 192 bytes |
| EEPROM Data Memory | None |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns |
| Operating Voltage Range | 4 V to 6 V |
| I/O Pins | 33 |
| A/D Converter | 8 channels, 8-bit |
| Capture/Compare/PWM (CCP) | 1 module |
| USART | 1 (SCI) |
| Synchronous Serial Port (SSP) | SPI / I2C |
| Timers | Timer0, Timer1, Timer2 + Watchdog |
| Interrupt Sources | 15 |
| Operating Temperature Range | -40C to +125C (Industrial / -E grade) |
| Package | 40-pin PDIP (0.600", 15.24 mm) |
| Mounting Type | Through-Hole |
| Speed Grade Suffix | -20 (20 MHz) |
| Temperature Grade Suffix | -E (Extended) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC16C74A-20E/P Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input / Programming voltage |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / Analog input 2 |
| Pin 5 | RA3/AN3/VREF — PORTA bit 3 / Analog input 3 / Voltage reference |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / Analog input 4 / SPI slave select |
| Pin 8 | RE0/RD/AN5 — PORTE bit 0 / Read control / Analog input 5 |
| Pin 9 | RE1/WR/AN6 — PORTE bit 1 / Write control / Analog input 6 |
| Pin 10 | RE2/CS/AN7 — PORTE bit 2 / Chip select / Analog input 7 |
| Pin 11 | VDD — Positive supply voltage |
| Pin 12 | VSS — Ground |
| Pin 13 | OSC1/CLKIN — Oscillator crystal input / external clock |
| Pin 14 | OSC2/CLKOUT — Oscillator crystal output / clock out |
| Pin 15 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator out / Timer1 clock in |
| Pin 16 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator in / CCP2 |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / Capture Compare PWM 1 |
| Pin 18 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 19 | RD0/PSP0 — PORTD bit 0 / Parallel Slave Port bit 0 |
| Pin 20 | RD1/PSP1 — PORTD bit 1 / Parallel Slave Port bit 1 |
| Pin 21 | RD2/PSP2 — PORTD bit 2 / Parallel Slave Port bit 2 |
| Pin 22 | RD3/PSP3 — PORTD bit 3 / Parallel Slave Port bit 3 |
| Pin 23 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 24 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 25 | RC6/TX/CK — PORTC bit 6 / USART TX / USART clock |
| Pin 26 | RC7/RX/DT — PORTC bit 7 / USART RX / USART data |
| Pin 27 | RD4/PSP4 — PORTD bit 4 / Parallel Slave Port bit 4 |
| Pin 28 | RD5/PSP5 — PORTD bit 5 / Parallel Slave Port bit 5 |
| Pin 29 | RD6/PSP6 — PORTD bit 6 / Parallel Slave Port bit 6 |
| Pin 30 | RD7/PSP7 — PORTD bit 7 / Parallel Slave Port bit 7 |
| Pin 31 | VSS — Ground |
| Pin 32 | VDD — Positive supply voltage |
| Pin 33 | RB0/INT — PORTB bit 0 / External interrupt |
| Pin 34 | RB1 — PORTB bit 1 |
| Pin 35 | RB2 — PORTB bit 2 |
| Pin 36 | RB3 — PORTB bit 3 |
| Pin 37 | RB4 — PORTB bit 4 |
| Pin 38 | RB5 — PORTB bit 5 |
| Pin 39 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 40 | RB7/PGD — PORTB bit 7 / ICSP data |
Typical Applications
PIC16C74A-20E/P is suitable for 7 applications: Industrial Process Control, Motor Control and PWM Drive, Instrumentation and Data Acquisition, HVAC Control Systems, Security and Alarm Panels, Automotive Body and Chassis Modules, Embedded Control with Integrated Peripherals.
Industrial Process Control
The PIC16C74A-20E/P fits industrial process control because its -40C to +125C extended temperature range tolerates factory floor conditions, while the integrated 8-channel 8-bit A/D converter reads multiple thermocouples, pressure transducers, or 4-20 mA loop signals without external ADC chips. At 20 MHz the core delivers 5 MIPS throughput, sufficient for PID loops at 1 kHz sampling rates typical of valve-position or flow-control systems. The 192-byte RAM sustains moving-average filters and trend buffers. Place the device on a 40-pin PDIP carrier with the USART driving an RS-485 transceiver for SCADA telemetry; unlike a discrete PLC, this MCU integrates timing, comms, and analog front-end in a single 1-dollar-class part.
Recommended
Motor Control and PWM Drive
The PIC16C74A-20E/P's on-chip Capture/Compare/PWM (CCP) module and Timer2 provide hardware PWM generation suitable for brushed DC, unipolar stepper, or small BLDC motor drive up to modest switching frequencies. At 20 MHz, the 10-bit PWM resolution is achievable with sub-microsecond edge placement for low-speed precision positioning. Its 33 digital I/O pins accept quadrature encoder inputs for closed-loop feedback, while the 8-bit A/D samples motor current via shunt resistors for torque-limiting. Place the MCU on a 40-pin PDIP with opto-isolated gate drivers feeding the IGBT bridge; the integrated CCP removes the need for external PWM generator ICs.
Recommended
Instrumentation and Data Acquisition
The PIC16C74A-20E/P serves instrumentation and data acquisition well due to its 8-channel 8-bit A/D with multiplexed inputs and the integrated USART plus SSP serial port. Engineers can read up to eight analog sensors at sampling rates above 10 kHz aggregate and stream results via SPI or RS-232 to a host logger. The 7 KB OTP program memory accommodates calibrated linearization tables for thermocouples or RTDs. Place the MCU on a 40-pin PDIP with input protection and instrumentation amplifiers on the analog front-end; the on-chip A/D eliminates the cost and complexity of a dedicated ADC chip in mid-resolution measurement systems.
Recommended
HVAC Control Systems
The PIC16C74A-20E/P suits HVAC control because its 33 I/O pins can drive triac-fired relays for compressor, fan, and damper control while the 8-channel A/D monitors return-air temperature, humidity sensors, and duct pressure. Its -40C to +125C grade survives rooftop unit thermal cycling, and the 4 V to 6 V supply range accommodates 5 V regulated rails from the HVAC transformer. The 5 MIPS CPU executes thermostat scheduling algorithms and PID blower control with sufficient margin. Place the MCU on a 40-pin PDIP in the appliance control board alongside zero-cross optocouplers for line-voltage triac gating.
Recommended
Security and Alarm Panels
The PIC16C74A-20E/P suits security and alarm panels because of its 33 digital inputs for PIR sensors, door contacts, glass-break detectors, and keypad matrix, with the 8-bit A/D monitoring battery voltage and loop current. The USART supports dialer modem or central-station communication via RS-232, while the SSP can drive an LCD or I2C keypad controller. The extended -40C to +125C range handles unconditioned installation environments. Place the device on a 40-pin PDIP with watchdog timer enabled for fail-safe operation; OTP memory provides anti-tamper code protection that cannot be overwritten in the field.
Recommended
Automotive Body and Chassis Modules
Although automotive designs typically require AEC-Q100 qualified parts, the PIC16C74A-20E/P's -40C to +125C extended temperature range and integrated peripherals have made it a long-standing choice for aftermarket and non-safety automotive subsystems such as lighting controllers, seat positioners, and instrument clusters. Its 33 I/O pins drive relays and read switches across multiple body harnesses, while the USART and SSP communicate with central body controllers. Place the device on a 40-pin PDIP in sealed modules with external CAN transceivers for higher-network integration; for production automotive, migrate to AEC-Q100 qualified PIC16F alternatives.
Recommended
Embedded Control with Integrated Peripherals
The PIC16C74A-20E/P fits general-purpose embedded control because it integrates a USART, SSP, CCP, three timers, a watchdog, and an 8-channel A/D into a single 40-pin PDIP device - eliminating external peripheral ICs and reducing board cost. Engineers can implement SPI-driven displays, I2C sensors, PWM outputs, and asynchronous serial comms simultaneously. The 7 KB OTP holds substantial state machines and lookup tables, while the 35-instruction RISC core accelerates code review and maintenance. Place the device on a 40-pin PDIP prototype board with ICD header for in-circuit debugging using MPLAB ICD 2 or 3.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C74A-20E/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F74-I/P | PIC16C74A-20/P | PIC16C74A-10E/P | PIC16C74A-04I/P | PIC16C74A-10/P |
|---|---|---|---|---|---|---|
| Package | 40-pin PDIP | 40-pin PDIP (same) | 40-pin PDIP (same) | 40-pin PDIP (same) | 40-pin PDIP (same) | 40-pin PDIP (same) |
| Brand | Microchip Technology | Microchip Technology (same) | Microchip Technology (same) | Microchip Technology (same) | Microchip Technology (same) | Microchip Technology (same) |
| Program Memory Type | OTP (7 KB) | Flash (7 KB) | OTP (7 KB) | OTP (7 KB) | OTP (7 KB) | OTP (7 KB) |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 10 MHz | 4 MHz | 10 MHz |
| Operating Temperature | -40C to +125C (E grade) | -40C to +85C (I grade) | 0C to +70C (commercial) | -40C to +125C (E grade) | -40C to +85C (I grade) | 0C to +70C (commercial) |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| A/D Converter | 8-channel, 8-bit | 8-channel, 8-bit | 8-channel, 8-bit | 8-channel, 8-bit | 8-channel, 8-bit | 8-channel, 8-bit |
| Recommended for New Designs | No (legacy OTP) | Yes (flash-based) | No (legacy OTP) | No (legacy OTP) | No (legacy OTP) | No (legacy OTP) |
Key Differentiators
- Flash-based successor with identical pinout and peripherals (vs PIC16F74-I/P)
- Higher 20 MHz clock rate versus lower-speed grades (vs PIC16C74A-10E/P)
- Extended -40C to +125C temperature range (vs PIC16C74A-20/P)
Design Notes
The PIC16C74A-20E/P requires a stable 4 V to 6 V supply on pins 11 and 32, with both VDD pins bypassed by 100 nF ceramic capacitors placed within 5 mm of the package and a bulk 10 uF tantalum or aluminum polymer capacitor on the supply rail. For analog reference, decouple AVdd and Vref with 10 uF plus 100 nF to suppress digital switching noise coupling into the 8-bit A/D. Brown-out reset should be enabled in configuration fuses to ensure deterministic startup on noisy industrial rails.
Do not assume the PIC16C74A-20E/P is in active production: Microchip's product page directs designers to the PIC16F74 for new work because the PIC16C74A OTP family is legacy. New designs should adopt the flash-based PIC16F74-I/P, which shares the same 40-pin PDIP footprint and peripheral set but provides in-system reprogramming. Reserve the PIC16C74A-20E/P for maintaining field-deployed equipment where firmware is already OTP-locked and validated.
Route the 20 MHz oscillator traces (OSC1/OSC2) as short as possible and guard them with a ground ring to avoid coupling into analog inputs. Place the A/D input traces away from digital switching lines; if both analog and digital signals must cross, do so at right angles. Use a ground plane on the layer immediately beneath the MCU and avoid running signal traces beneath the oscillator to prevent capacitive loading and frequency drift across the -40C to +125C range.
The 40-pin PDIP footprint has 0.100" (2.54 mm) pin pitch and 0.600" (15.24 mm) row spacing, standard for through-hole prototype boards. Include an ICSP header (PGC on RB6, PGD on RB7, MCLR/VPP on pin 1, VDD, VSS) so MPLAB ICD 2/3 or PICkit 3 can program and debug the device in-circuit. If the design targets surface-mount assembly, choose the PIC16C74A-20/SO or PIC16C74A-20/PQ variants instead - they are not pin-compatible with the /P DIP package.
Compliance Information
RoHS and lead-free compliance per Microchip product page. Not AEC-Q100 qualified - the PIC16C74A-20E/P is intended for industrial, commercial, and consumer applications, not automotive safety-critical systems.
