PIC16LC74A-04I/PT - 8-Bit MCU, 4MHz, 7KB OTP, 44-TQFP | Microchip
MPN: PIC16LC74A-04I/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.42 | $5.42 |
| 10 | $4.89 | $48.90 |
| 100 | $4.32 | $432.00 |
| 500 | $3.78 | $1,890.00 |
| 1,000 | $3.35 | $3,350.00 |
PIC16LC74A-04I/PT Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (ROM/Flash/OTP), data memory (RAM), I/O peripherals, and often timers, communication interfaces, and analog blocks. The PIC16C family sits within Microchip's mid-range architecture (14-bit instruction word), providing a balance of code density, peripheral integration, and deterministic interrupt response. Microcontrollers sit within the broader taxonomy of embedded processors -> microcontrollers -> 8-bit microcontrollers -> CMOS microcontrollers -> mid-range MCUs.
Key features of the PIC16LC74A-04I/PT include its 4 MHz maximum oscillator frequency, integrated 8-bit A/D converter, USART/SCI and SSP (SPI/I2C) communication peripherals, multiple 8/16-bit timer modules, and 33 digital I/O lines. The wide operating voltage range and CMOS process yield low current typical draw at full operation, making it suitable for battery-powered and industrial applications.
Architecturally, the PIC16LC74A uses a Harvard RISC core with 14-bit-wide instructions and 8-bit-wide data, allowing single-cycle instruction execution except for branches (2 cycles). The OTP program memory supports one-time programming for low-volume or production units where code stability is paramount, while the on-chip peripherals are mapped via a banked register architecture familiar to PIC mid-range developers.
Typical applications include industrial control systems, automotive subsystems (non-safety-critical), appliance controls, sensor signal conditioning, low-speed data acquisition, and embedded control loops where deterministic timing and a mature toolchain (MPLAB, MPASM, C18) are valued. The 44-TQFP package provides ample I/O for moderate-complexity designs.
When designing with this part, note that OTP memory cannot be re-programmed in-circuit; for prototype iterations, choose a Flash-based sibling such as the PIC16F74 or PIC16F874 in the same package. The 'I' suffix denotes the industrial temperature grade (-40C to +85C), and 'LC' denotes the low-voltage CMOS process variant.
Drop-in alternatives for PIC16LC74A-04I/PT — 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 PIC16LC74A-04I/PT (same form factor and footprint) — differing in A/D Converter, Core Architecture, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F74-I/PT
✅ Drop-In✓ In Stock
$5.55 / Unit
View Datasheet →PIC16LC74A-04I/PQ
✅ Drop-In✓ In Stock
$5.1 / Unit
View Datasheet →PIC16LC74A-04/PT
✅ Drop-In✓ In Stock
$3.75 / Unit
View Datasheet →PIC16F874-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F747-I/PT
✅ Drop-In✓ In Stock
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View Datasheet →PIC16F887-I/PT
✅ Drop-In✓ In Stock
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View Datasheet →PIC16LC74A-04I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit (PIC16C mid-range, 14-bit instruction) |
| Program Memory | 7 KB (4K x 14) OTP |
| Data RAM | 192 bytes |
| Maximum Clock Frequency | 4 MHz |
| I/O Pins | 33 |
| Package | 44-pin TQFP (10x10 mm) |
| Mounting Type | Surface Mount |
| Temperature Grade | Industrial (-40C to +85C) |
| A/D Converter | 8-bit integrated |
| Communication Peripherals | USART/SCI, SSP (SPI/I2C) |
| Timer Modules | Multiple 8/16-bit timers |
| Memory Type | OTP (One-Time Programmable) |
PIC16LC74A-04I/PT Pin Configuration
| Pin 1 | OSC1/CLKI — Oscillator input / external clock |
| Pin 2 | OSC2/CLKO — Oscillator output |
| Pin 3 | MCLR/VPP — Reset input / programming voltage |
| Pin 4 | RA0/AN0 — Digital I/O / analog input 0 |
| Pin 5 | RA1/AN1 — Digital I/O / analog input 1 |
| Pin 6 | RA2/AN2 — Digital I/O / analog input 2 |
| Pin 7 | RA3/AN3/VREF — Digital I/O / analog input 3 / A/D reference |
| Pin 8 | RA4/T0CKI — Digital I/O / Timer0 clock |
| Pin 9 | RA5/AN4/SS — Digital I/O / analog input 4 / SPI slave select |
| Pin 10 | VSS — Ground |
| Pin 11 | VDD — Positive supply |
| Pin 12 | RB0/INT — Digital I/O / external interrupt |
| Pin 13 | RB1 — Digital I/O |
| Pin 14 | RB2 — Digital I/O |
| Pin 15 | RB3 — Digital I/O |
| Pin 16 | RB4 — Digital I/O |
| Pin 17 | RB5 — Digital I/O |
| Pin 18 | RB6/PGC — Digital I/O / ICSP clock |
| Pin 19 | RB7/PGD — Digital I/O / ICSP data |
| Pin 20 | VSS — Ground |
| Pin 21 | VDD — Positive supply |
| Pin 22 | RC0/T1OSO/T1CKI — Digital I/O / Timer1 oscillator output / clock |
| Pin 23 | RC1/T1OSI/CCP2 — Digital I/O / Timer1 oscillator input / CCP2 |
| Pin 24 | RC2/CCP1 — Digital I/O / CCP1 |
| Pin 25 | RC3/SCK/SCL — Digital I/O / SPI clock / I2C clock |
| Pin 26 | RC4/SDI/SDA — Digital I/O / SPI data in / I2C data |
| Pin 27 | RC5/SDO — Digital I/O / SPI data out |
| Pin 28 | RC6/TX/CK — Digital I/O / USART TX / clock |
| Pin 29 | RC7/RX/DT — Digital I/O / USART RX / data |
| Pin 30 | VSS — Ground |
| Pin 31 | VDD — Positive supply |
| Pin 32 | RD0 — Digital I/O |
| Pin 33 | RD1 — Digital I/O |
| Pin 34 | RD2 — Digital I/O |
| Pin 35 | RD3 — Digital I/O |
| Pin 36 | RD4 — Digital I/O |
| Pin 37 | RD5 — Digital I/O |
| Pin 38 | RD6 — Digital I/O |
| Pin 39 | RD7 — Digital I/O |
| Pin 40 | VSS — Ground |
| Pin 41 | VDD — Positive supply |
| Pin 42 | RE0/RD/AN5 — Digital I/O / parallel port read / analog input 5 |
| Pin 43 | RE1/WR/AN6 — Digital I/O / parallel port write / analog input 6 |
| Pin 44 | RE2/CS/AN7 — Digital I/O / parallel port chip select / analog input 7 |
Typical Applications
PIC16LC74A-04I/PT is suitable for 6 applications: Industrial Control Systems, Appliance Control Boards, Low-Speed Data Acquisition, Sensor Signal Conditioning and Interface, Automotive Subsystems (non-safety), Embedded Control Training and Prototyping.
Industrial Control Systems
The PIC16LC74A-04I/PT's 33 I/O pins and integrated peripherals make it well suited for industrial control panels driving relays, solenoid drivers, and discrete indicator LEDs. Its 4 MHz CPU clock executes instructions deterministically at 1 MIPS, sufficient for PID loops, sequencing logic, and sensor multiplexing in PLC-style designs. The industrial temperature grade (-40C to +85C) supports factory-floor environments with temperature swings.
Recommended
Appliance Control Boards
The PIC16LC74A-04I/PT is commonly deployed in white-goods appliance controllers (washing machines, dishwashers, microwave ovens) where its 7 KB OTP memory holds locked firmware and the USART/SSP peripherals interface to display modules and sensor arrays. The wide operating voltage range and low current typical draw at CMOS clocks support energy-conscious appliances meeting Energy Star targets.
Recommended
Low-Speed Data Acquisition
The PIC16LC74A-04I/PT's integrated 8-bit A/D converter with multiple input channels and USART/SCI peripheral makes it a cost-effective front end for low-speed data acquisition systems sampling temperature, pressure, or voltage at sub-kHz firmware-controlled intervals. 192 bytes of RAM buffers small sample windows before forwarding via serial, while the deterministic PIC core ensures fixed ADC acquisition timing.
Recommended
Sensor Signal Conditioning and Interface
The PIC16LC74A-04I/PT's SSP (SPI/I2C) peripheral enables it to act as a sensor hub reading digital sensors and forwarding processed data to a host MCU. With 33 I/O ports, it can simultaneously scan multiple sensor channels and drive character LCDs or 7-segment displays. Its CMOS process ensures low current draw for battery-backed sensor interfaces in remote monitoring stations.
Recommended
Automotive Subsystems (non-safety)
While not AEC-Q100 qualified, the PIC16LC74A-04I/PT is used in legacy automotive subsystems (interior lighting, mirror controllers, accessory timers) where its 44-TQFP industrial temperature grade and mature toolchain enable cost-sensitive designs. Designers transitioning to modern automotive should use AEC-Q100-qualified PIC16F or dsPIC equivalents from Microchip's automotive portfolio.
Recommended
Embedded Control Training and Prototyping
The PIC16LC74A-04I/PT's mature MPLAB toolchain, MPASM assembler, and abundant third-party example code make it a popular choice for university courses and embedded systems training where students learn timer interrupts, A/D conversion, and serial communication. Its 44-TQFP package exposes enough I/O for breadboard-friendly breakout boards and peripheral experimentation.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC74A-04I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F74-I/PT | PIC16LC74A-4I/PQ | PIC16LC74A-04/PT | PIC16F874-I/PT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-TQFP (10x10 mm) | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same die, MQFP body | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same |
| Program Memory | 7 KB OTP | 7 KB Flash | 7 KB OTP (same) | 7 KB OTP (same) | 7 KB Flash |
| Data RAM | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 368 bytes |
| Max Clock Frequency | 4 MHz | 20 MHz | 4 MHz | 4 MHz | 20 MHz |
| A/D Converter | 8-bit | 8-bit | 8-bit | 8-bit | 10-bit |
| I/O Pins | 33 | 33 | 33 | 33 | 33 |
| Temperature Grade | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Commercial (0C to +70C) | Industrial (-40C to +85C) |
| Memory Type | OTP (one-time) | Flash (reprogrammable) | OTP (one-time) | OTP (one-time) | Flash (reprogrammable) |
Key Differentiators
- OTP memory for locked production firmware (vs PIC16F74-I/PT)
- Low-voltage CMOS 'LC' process (vs PIC16C74A-04I/PT)
- 44-TQFP package exposes 33 I/O pins with full peripheral set (vs PIC16F874-I/PT)
Design Notes
OTP memory cannot be re-programmed in-circuit. A single bad write bricks the part. For development, use the Flash-based PIC16F74-I/PT in the same 44-TQFP package, then swap to PIC16LC74A-04I/PT only after firmware is fully validated and frozen. Always verify code in Flash hardware before ordering masked/OTP equivalents.
Place decoupling capacitors (100 nF ceramic + 10 uF bulk) as close as possible to each VDD/VSS pair (pins 11/10, 21/20, 31/30, 41/40). The PIC16LC74A-04I/PT has four VDD/VSS pairs; failing to decouple all four can inject digital switching noise into the A/D converter via shared internal power traces. A single 100 nF at pin 11 is not sufficient.
Keep the OSC1/OSC2 crystal traces short and surrounded by a ground guard ring to reduce EMI susceptibility. For 4 MHz operation, a parallel-resonant crystal with 22-33 pF load capacitors to ground is standard. Place the MCLR pull-up resistor (typically 10 kohm) close to pin 1 to ensure clean reset behavior during power-up.
The 44-TQFP (10x10 mm) package has 0.8 mm pitch and is surface-mount. Hand-soldering is difficult; plan for reflow or hot-air rework. Exposed pad variants are absent on this package, so no thermal pad landing is required - VDD/VSS pins provide thermal dissipation paths. Follow IPC-7351 land pattern recommendations for optimal yield.
The 'I' suffix denotes industrial temperature grade (-40C to +85C); the non-'I' PIC16LC74A-04/PT is commercial grade (0C to +70C). Substituting an 'I' part on a design intended for commercial environments is fine, but using the commercial part in an industrial design will fail temperature testing. Verify the exact suffix when ordering to avoid thermal-range surprises.
Compliance Information
Compliance information not present in the verified web data; set to 'unknown' rather than guess. Per Microchip's general policy, parts in TQFP packages are typically lead-free but this specific part number's compliance status was not in the data; refer to manufacturer's product page or compliance certificate to confirm.