PIC16C74BT-04I/PQ - 8-bit MCU, 7KB OTP, 4MHz, 44-MQFP | Microchip
MPN: PIC16C74BT-04I/PQ ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.5 | $9.50 |
| 10 | $8.55 | $85.50 |
| 100 | $7.65 | $765.00 |
| 500 | $6.85 | $3,425.00 |
| 1,000 | $6.1 | $6,100.00 |
PIC16C74BT-04I/PQ Overview
A microcontroller (MCU) is a single-chip computer that contains a CPU, non-volatile program memory, working RAM, and configurable peripherals. Within the broader semiconductor taxonomy, the PIC16C74BT-04I/PQ sits in the 8-bit mid-range MCU category, which itself is a subset of the embedded microcontroller family, sitting below 16-bit and 32-bit MCUs in computational throughput but excelling in deterministic interrupt response, low cost, and ease of programming. OTP memory means the device is programmed once at production; for re-programmable equivalents, the PIC16F74 in the flash-based PIC16F family is the modern counterpart.
Key features include 33 digital I/O pins, three serial communication peripherals (I2C/SPI, SPI, and UART/USART), an 8-channel 8-bit ADC, Brown-out Detect and Power-On Reset (POR) for robust supply supervision, and a wide 2.5V to 6.0V operating voltage range. The device supports external oscillator operation, allowing the system designer to choose crystal, resonator, or RC oscillator sources matched to EMI and timing requirements.
The PIC16C74BT-04I/PQ is built on Microchip's CMOS, fully-static mid-range architecture, providing low power consumption and instruction execution in a single instruction cycle (excluding branches). With 14-bit instruction width, code density is excellent, allowing rich peripheral interaction in 7KB of memory. The integrated ADC with eight channels makes analog sensor interfacing straightforward without external components.
Typical applications include industrial control systems, appliance and HVAC controllers, automotive body electronics, instrumentation front-ends with analog inputs, and embedded sensor hubs requiring UART or SPI host communication. Because the part is OTP, it is best suited to mature, high-volume products where the firmware is finalized and ongoing field updates are not required.
Designers should pay attention to the difference between the -04 speed grade (4 MHz) and the -20 speed grade (20 MHz) within the same family; this variant runs at 4 MHz maximum oscillator frequency. The 'T' suffix indicates tape-and-reel packaging, and 'I' indicates the industrial temperature grade.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes - including pin-compatibility analysis across the PIC16C74B and PIC16C73B families - that are not consolidated in any single manufacturer datasheet or distributor listing.
Drop-in alternatives for PIC16C74BT-04I/PQ — 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 PIC16C74BT-04I/PQ (same form factor and footprint) — differing in Package, Core Architecture, RoHS Status, Serial Interfaces, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C74BT-04/PQ
✅ Drop-In✓ In Stock
$5.6 / Unit
View Datasheet →PIC16C74BT-04E/PQ
✅ Drop-In✓ In Stock
$7.9 / Unit
View Datasheet →PIC16C74B-04/PQ
✅ Drop-In✓ In Stock
$7.25 / Unit
View Datasheet →PIC16C74B-04I/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C74B-04E/PQ
✅ Drop-In✓ In Stock
$9.95 / Unit
View Datasheet →ATMEGA8515L-8AUR
✅ Drop-In✓ In Stock
$1.98 / Unit
View Datasheet →PIC16C74BT-04I/PQ Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC16CXX mid-range |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 7KB (4K x 14 words) |
| Data RAM | 192 x 8 bytes |
| Maximum Clock Frequency | 4 MHz |
| Operating Voltage Range | 2.5 V to 6.0 V |
| Number of I/O Pins | 33 |
| ADC | 8-channel, 8-bit |
| Communication Peripherals | I2C/SPI, SPI, UART/USART |
| Package | 44-MQFP (10x10 mm), 'PQ' designator |
| Mounting Type | Surface Mount |
| Temperature Grade | Industrial (-40C to +85C) |
| Oscillator Type | External |
| Reset / Supervision | Brown-out Detect, Power-On Reset (POR) |
| Instruction Width | 14 bits |
| Instruction Cycle | 1 cycle (4 clock periods) |
| Process Technology | CMOS, fully static |
PIC16C74BT-04I/PQ Pin Configuration
| Pin 1 | MCLR/Vpp — Master Clear (reset) input / programming voltage |
| Pin 2 | RA0/AN0 — PORTA bit 0 / ADC analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / ADC analog input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / ADC analog input 2 |
| Pin 5 | RA3/AN3/VREF — PORTA bit 3 / ADC input 3 / voltage reference |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / ADC input 4 / SPI slave select |
| Pin 8 | RE0/RD — PORTE bit 0 / parallel port read control |
| Pin 9 | RE1/WR — PORTE bit 1 / parallel port write control |
| Pin 10 | RE2/CS — PORTE bit 2 / parallel port chip select |
| Pin 11 | VDD — Positive supply voltage |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKIN — External oscillator input / clock in |
| Pin 14 | OSC2/CLKOUT — External oscillator output / clock out |
| Pin 15 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator out / clock in |
| Pin 16 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator in / CCP2 |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM1 |
| Pin 18 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 19 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 20 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 21 | RC6/TX/CK — PORTC bit 6 / UART transmit / clock |
| Pin 22 | RC7/RX/DT — PORTC bit 7 / UART receive / data |
| Pin 23 | RD0 — PORTD bit 0 |
| Pin 24 | RD1 — PORTD bit 1 |
| Pin 25 | RD2 — PORTD bit 2 |
| Pin 26 | RD3 — PORTD bit 3 |
| Pin 27 | RD4 — PORTD bit 4 |
| Pin 28 | RD5 — PORTD bit 5 |
| Pin 29 | RD6 — PORTD bit 6 |
| Pin 30 | RD7 — PORTD bit 7 |
| Pin 31 | VSS — Ground reference |
| 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 |
| Pin 41 | AN5 — ADC analog input 5 |
| Pin 42 | AN6 — ADC analog input 6 |
| Pin 43 | AN7 — ADC analog input 7 |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C74BT-04I/PQ is suitable for 7 applications: Industrial Control Systems, Appliance and HVAC Controllers, Automotive Body Electronics, Instrumentation Front-Ends, Embedded Sensor Hubs, Consumer Electronics Controllers, Educational and Development Platforms.
Industrial Control Systems
The PIC16C74BT-04I/PQ fits industrial control boards where its 33 digital I/O can drive relays, switches, and status LEDs while the 8-channel 8-bit ADC reads analog sensors. With a 4 MHz mid-range core executing most instructions in one cycle and Brown-out Detect plus Power-On Reset, the part tolerates noisy 24V-derived 5V rails. Industrial temperature grade (-40C to +85C) supports factory floor enclosures without derating.
Recommended
Appliance and HVAC Controllers
The PIC16C74BT-04I/PQ drives compressor, fan, and valve control loops in white-goods and HVAC systems. Its UART/USART interfaces to a wall thermostat or display panel, while the I2C/SPI bus reads temperature and humidity sensors. With 192 bytes of RAM and a 4 MHz instruction rate, the part handles PID loops and user-interface scanning in real time, and the 2.5V to 6.0V Vdd range accommodates rectified 5V rails typical in appliance power supplies.
Recommended
Automotive Body Electronics
Body-control modules for lighting, mirror, and seat positioning benefit from the PIC16C74BT-04I/PQ's 33 I/O and 8-bit ADC. SPI/UART links connect to BCM bus masters and remote switch panels. While this part is OTP-only and not AEC-Q100 qualified, design teams using it for non-safety automotive subsystems find the 4 MHz core deterministic for switch debouncing and PWM generation. Industrial temperature grade covers in-cabin environments.
Recommended
Instrumentation Front-Ends
Bench-top meters, panel indicators, and process-control instruments use the PIC16C74BT-04I/PQ for analog conditioning and display driving. Its 8-channel ADC samples up to 4 inputs at the part's throughput, supporting temperature, pressure, and 4-20 mA loop conversions. The 7KB OTP holds calibration tables and menu logic; UART outputs to a host PC or external display controller. Brown-out Detect prevents corrupted readings during supply dips.
Recommended
Embedded Sensor Hubs
Distributed sensor nodes for environmental monitoring use the PIC16C74BT-04I/PQ as a low-cost aggregator. Its UART links to a wireless module (XBee, LoRa) while the I2C/SPI bus reads multiple digital sensors. At 4 MHz with CMOS static design, current draw is minimal between samples. The 33 I/O drives status LEDs and control outputs, and the 192-byte RAM stores sample buffers and protocol framing.
Recommended
Consumer Electronics Controllers
The PIC16C74BT-04I/PQ powers mature consumer products where the firmware is finalized and OTP is acceptable: exercise equipment, kitchen appliances, and toy controllers. Its UART/I2C/SPI set interfaces to displays, audio chips, and user inputs. The 7KB OTP holds full application code including menu logic and motor-control routines; industrial temp grade covers indoor and sheltered-outdoor use cases.
Recommended
Educational and Development Platforms
Universities and training labs use the PIC16C74BT-04I/PQ as a teaching vehicle for mid-range 8-bit MCU fundamentals. Its instruction set, 14-bit word width, and rich peripheral set provide a complete learning target before graduates move to 32-bit platforms. With 33 I/O on the 44-MQFP footprint, breakout boards expose enough pins for breadboard prototyping, and the OTP memory enforces good code-revision discipline in coursework.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C74BT-04I/PQ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C74BT-04/PQ | PIC16C74BT-04E/PQ | PIC16C74B-04/PQ | PIC16C74B-04I/PQ | PIC16C74B-04E/PQ | ATMEGA8515L-8AU |
|---|---|---|---|---|---|---|---|
| Package | 44-MQFP (PQ) 10x10 mm | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-TQFP (AU) - same footprint class |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology (Atmel legacy) |
| Core Architecture | 8-bit PIC mid-range | 8-bit PIC mid-range | 8-bit PIC mid-range | 8-bit PIC mid-range | 8-bit AVR | ||
| Program Memory | 7KB OTP (4K x 14) | 7KB OTP | 7KB OTP | 8KB Flash (+14%) | |||
| Data RAM | 192 x 8 bytes | 192 x 8 bytes | 192 x 8 bytes | 512 bytes (+167%) | |||
| Maximum Clock | 4 MHz | 4 MHz | 4 MHz | 8 MHz (+100%) | |||
| I/O Pins | 33 | 33 | 33 | 35 | |||
| ADC | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit | No ADC | |||
| Temperature Grade | Industrial -40C to +85C | Commercial 0C to +70C | Extended -40C to +125C | Industrial -40C to +85C | Extended -40C to +125C | Industrial -40C to +85C |
Key Differentiators
- Industrial temperature grade at -40C to +85C (vs PIC16C74BT-04/PQ)
- Integrated 8-channel 8-bit ADC (vs ATMEGA8515L-8AU)
- Deterministic 4-cycle interrupt response (vs ATMEGA8515L-8AU)
Design Notes
Power the PIC16C74BT-04I/PQ from a clean regulated 5V or 3.3V rail with a decoupling network of 100 nF ceramic plus 10 uF electrolytic placed within 10 mm of Vdd pins 11 and 32. According to the PIC16C7X datasheet, both Vdd pins must be tied to the same supply, and both Vss pins (12 and 31) must be grounded. Brown-out Detect and Power-On Reset require the supply rise time to remain within the datasheet's specified slope to avoid spurious resets on power-up.
Route the external oscillator traces (OSC1 pin 13, OSC2 pin 14) as short, symmetric loops and place the crystal or resonator within 5 mm of the MCU to minimize EMI pickup. According to the PIC16C7X datasheet, the load capacitors for the crystal must match the manufacturer's recommended values (typically 15-33 pF) and should be grounded to the same Vss plane as the MCU. Avoid routing digital switching signals adjacent to OSC1/OSC2 to prevent clock jitter.
Because the PIC16C74BT-04I/PQ is OTP (One-Time Programmable), firmware bugs cannot be patched in the field. Verify firmware on a flash-based equivalent (PIC16F74-04I/PQ in the same 44-MQFP footprint) before committing to OTP programming. According to Microchip migration notes, the PIC16F74 is pin-compatible and supports in-circuit serial programming (ICSP) via the RB6/RB7 pins, allowing prototype iteration before final OTP burn-in production.
The PIC16C74BT-04I/PQ's analog inputs (RA0-RA5, RE0-RE2 alternate AN5-AN7) are sensitive to digital switching noise on adjacent PORTD or PORTC pins. According to the PIC16C7X datasheet, AC coupling from digital traces can inject 1-2 LSB error into the 8-bit ADC; route analog inputs separated from digital outputs, place a small RC filter (1 kohm + 100 nF) at each analog input when the source impedance is high, and ground the ADC Vref to a quiet analog ground island.
Compliance Information
This part is OTP-only and listed as obsolete by Microchip. Compliance status not confirmed in the verified distributor data; consult Microchip product discontinuation notices for the latest environmental compliance documentation before substituting into new designs.
