PIC16C74A-04I/PT - 8-bit MCU, 7KB OTP, 4MHz, 44-TQFP | Microchip
MPN: PIC16C74A-04I/PT β Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.95 | $8.95 |
| 10 | $8.05 | $80.50 |
| 100 | $7.15 | $715.00 |
| 500 | $6.45 | $3,225.00 |
| 1,000 | $5.85 | $5,850.00 |
PIC16C74A-04I/PT Overview
Background knowledge: an 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, non-volatile program memory, volatile data RAM, and peripheral interfaces on one silicon die. Within the MCU hierarchy, the PIC16C74A belongs to the PIC16 mid-range family (PIC10/12/16/18 families walk up to 8-bit MCUs; PIC24/dsPIC to 16-bit; PIC32 to 32-bit). OTP program memory means the device can be programmed once and is intended for low-to-mid volume production where flash reprogrammability is not required; flash-based PIC16F equivalents offer the same peripherals with in-circuit reprogrammability.
Key features of the PIC16C74A include 7KB OTP program memory, 192 x 8 RAM, a 14-bit instruction word, 33 I/O pins shared with peripheral functions, and an integrated 8-bit A/D converter. The 4 MHz oscillator speed yields a 250 ns instruction cycle, sufficient for control loops and human-interface response times. The architecture is Harvard (separate program/data buses), and the RISC core executes 35 single-cycle instructions.
Typical applications include industrial control panels, sensor signal conditioning, motor control, embedded data acquisition, and consumer appliance control. The integrated A/D converter removes the need for an external ADC in many systems, reducing both BOM cost and PCB area.
When designing with the PIC16C74A, note that the OTP memory requires a programmer that supports the PIC16C7X family (e.g., PICSTART Plus, MPLAB PM3, or compatible third-party tools). The newer flash-based PIC16F74 is a recommended migration path; both share the same 44-pin TQFP pinout. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the standalone manufacturer datasheet.
Drop-in alternatives for PIC16C74A-04I/PT β 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-04I/PT (same form factor and footprint) β differing in Package, Timers, Program Memory Size, Program Memory Type, A/D Converter.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F74-I/PT
β Drop-Inπ Reference alternative (not in catalog)
PIC16C74B-04I/PT
β Drop-Inβ In Stock
$6.1 / Unit
View Datasheet βPIC16C74A-20I/PT
β Drop-Inπ Reference alternative (not in catalog)
PIC16C77-04I/PT
β Drop-Inπ Reference alternative (not in catalog)
PIC16C76-04I/PT
β Drop-Inπ Reference alternative (not in catalog)
PIC16C74A-04I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 (8-bit RISC, Harvard) |
| Program Memory Size | 7 KB (4K x 14) OTP |
| RAM Size | 192 x 8 bytes |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle Time | 250 ns (4 MHz / 4) |
| Operating Supply Voltage | 5 V nominal |
| Number of I/O Pins | 33 |
| A/D Converter | 8-bit, integrated (per datasheet 30390e) |
| Package | 44-pin TQFP (PT) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (industrial, "I" grade) |
| Peripherals | USART, MSSP (SPI/I2C), CCP, Timers, ADC |
| Instruction Set | 35 single-cycle instructions (14-bit word) |
| Program Memory Type | OTP (One-Time-Programmable) |
PIC16C74A-04I/PT Pin Configuration
| Pin 1 | RC5/SDO β Digital I/O / SPI data out (MSSP) |
| Pin 2 | RC4/SDI/SDA β Digital I/O / SPI data in / I2C data |
| Pin 3 | RC3/SCK/SCL β Digital I/O / SPI/I2C clock |
| Pin 4 | RC2/CCP1 β Digital I/O / Capture-Compare-PWM 1 |
| Pin 5 | RC1/T1OSI/CCP2 β Digital I/O / Timer1 oscillator in / CCP2 |
| Pin 6 | RC0/T1OSO/T1CKI β Digital I/O / Timer1 oscillator out / ext clock in |
| Pin 7 | OSC1/CLKIN β Oscillator input / external clock |
| Pin 8 | OSC2/CLKOUT β Oscillator output / clock out |
| Pin 9 | MCLR/VPP β Master clear reset / programming voltage |
| Pin 10 | VSS β Ground reference |
| Pin 11 | VDD β Positive supply (5 V) |
| Pin 12 | RA0/AN0 β Digital I/O / analog input channel 0 |
| Pin 13 | RA1/AN1 β Digital I/O / analog input channel 1 |
| Pin 14 | RA2/AN2/VREF- β Digital I/O / analog input 2 / ADC VREF- |
| Pin 15 | RA3/AN3/VREF+ β Digital I/O / analog input 3 / ADC VREF+ |
| Pin 16 | RA4/T0CKI β Digital I/O / Timer0 clock input |
| Pin 17 | RA5/AN4/SS β Digital I/O / analog input 4 / SPI slave select |
| Pin 18 | RB0/INT β Digital I/O / external interrupt |
| Pin 19 | RB1 β Digital I/O |
| Pin 20 | RB2 β Digital I/O |
| Pin 21 | RB3 β Digital I/O |
| Pin 22 | RB4 β Digital I/O |
| Pin 23 | RB5 β Digital I/O |
| Pin 24 | RB6/PGC β Digital I/O / ICSP clock |
| Pin 25 | RB7/PGD β Digital I/O / ICSP data |
| Pin 26 | RC6/TX/CK β Digital I/O / USART TX / clock |
| Pin 27 | RC7/RX/DT β Digital I/O / USART RX / data |
| Pin 28 | RC4 β (see pin 2) Digital I/O |
| Pin 29 | RD0 β Digital I/O / PSP data |
| Pin 30 | RD1 β Digital I/O / PSP data |
| Pin 31 | RD2 β Digital I/O / PSP data |
| Pin 32 | RD3 β Digital I/O / PSP data |
| Pin 33 | RD4 β Digital I/O / PSP data |
| Pin 34 | RD5 β Digital I/O / PSP data |
| Pin 35 | RD6 β Digital I/O / PSP data |
| Pin 36 | RD7 β Digital I/O / PSP data |
| Pin 37 | RE0/RD/AN5 β Digital I/O / PSP read / analog input 5 |
| Pin 38 | RE1/WR/AN6 β Digital I/O / PSP write / analog input 6 |
| Pin 39 | RE2/CS/AN7 β Digital I/O / PSP chip select / analog input 7 |
| Pin 40 | VSS β Ground reference |
| Pin 41 | VDD β Positive supply (5 V) |
| Pin 42 | NC β Not connected (per datasheet) |
| Pin 43 | NC β Not connected (per datasheet) |
| Pin 44 | RC5 β (see pin 1) Digital I/O |
Typical Applications
PIC16C74A-04I/PT is suitable for 6 applications: Industrial Control Panels, Sensor Signal Conditioning, Small Motor Control (DC, Stepper), Embedded Data Acquisition Systems, Consumer Appliance Control, Automotive Body Electronics (Legacy).
Industrial Control Panels
The PIC16C74A-04I/PT suits industrial control panels because its 7KB OTP program memory holds substantial user-interface logic while 33 I/O pins directly drive relays, keypads, and 7-segment displays. The integrated 8-bit A/D converter reads panel-mount sensors (potentiometers, temperature transducers) without external ADC hardware, reducing BOM cost. The 4 MHz clock provides adequate responsiveness for human-interface timing and debounce routines, while the -40C to +85C industrial temperature range supports factory-floor environments. The 44-pin TQFP gives a compact footprint for high-density panel PCBs where a 40-pin PDIP would be too large.
Recommended
Sensor Signal Conditioning
The PIC16C74A-04I/PT is well-suited to sensor signal conditioning modules where its integrated 8-bit A/D converter samples analog inputs from thermistors, photocells, and bridge sensors at up to the device's ADC conversion rate. The USART and MSSP (SPI/I2C) peripherals stream conditioned data to a host controller or sensor bus. At 4 MHz the MCU executes a 250 ns instruction cycle, sufficient for digital filtering (moving average, simple IIR) before transmission. The 192-byte RAM accommodates small data buffers for sample averaging, and the OTP program memory protects calibration coefficients from accidental erasure in deployed field units.
Recommended
Small Motor Control (DC, Stepper)
For low-power DC and unipolar stepper motor control, the PIC16C74A-04I/PT provides dedicated CCP (Capture/Compare/PWM) modules that generate PWM drive signals without CPU overhead. The 33 I/O lines accommodate H-bridge direction/enable signals, limit-switch inputs, and tachometer feedback. Industrial temperature grade and 5 V operation simplify integration with standard opto-isolated gate drivers. A 4 MHz clock yields a PWM resolution suitable for 8-bit duty control of brushed motors. The integrated 8-bit ADC reads back shunt current or back-EMF for closed-loop control, while the OTP memory ensures firmware is locked against field tampering.
Recommended
Embedded Data Acquisition Systems
The PIC16C74A-04I/PT integrates the A/D converter, RAM, and USART peripherals required for compact embedded data loggers measuring slowly-changing analog signals. The 192-byte RAM supports circular sample buffers, and the USART streams data to a host PC or radio module. The PIC16C7X family instruction set includes hardware multiply and bit-manipulation that simplify sensor linearization. Industrial temperature grade enables outdoor or factory deployments, while OTP memory prevents accidental firmware corruption. The 44-pin TQFP footprint supports high-density PCB layouts where multiple analog channels are routed to the MCU.
Recommended
Consumer Appliance Control
The PIC16C74A-04I/PT fits consumer appliance controllers (coffee machines, washing-machine sub-modules, microwave displays) where cost dominates over reprogrammability. The 7KB OTP stores the appliance state machine, the 8-bit ADC reads water level / temperature sensors, and the 33 I/O pins drive triac-controlled AC loads via optocouplers. The 44-pin TQFP package delivers a compact footprint for the appliance main PCB. OTP memory protects manufacturers from unauthorized firmware copies in cost-sensitive consumer volumes. The PIC16C7X core is mature and supported by Microchip's long-term product programs.
Recommended
Automotive Body Electronics (Legacy)
While newer automotive designs use PIC18 or dsPIC parts, the PIC16C74A-04I/PT remains in service for legacy automotive body-electronics modules (window controllers, mirror adjusters, accessory drivers). The 44-pin TQFP package survives under-hood vibration when properly soldered, and the -40C to +85C industrial temperature grade covers most passenger-compartment deployments. The integrated A/D converter reads position-feedback pots, and the PWM modules drive small DC motors. For new automotive designs AEC-Q100-qualified PIC16F or PIC18 parts are mandatory; the PIC16C74A-04I/PT is a maintenance-only part in this domain.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C74A-04I/PT β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F74-I/PT | PIC16C74B-04I/PT | PIC16C74A-20I/PT | PIC16C77-04I/PT | PIC16C76-04I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-TQFP (PT) | 44-TQFP (PT) | 44-TQFP (PT) | 44-TQFP (PT) | 44-TQFP (PT) | 44-TQFP (PT) |
| Program Memory | 7 KB OTP | 7 KB Flash | 7 KB OTP | 7 KB OTP | 8 KB OTP | 14 KB OTP |
| Max Clock Frequency | 4 MHz | 20 MHz | 20 MHz (4 MHz @ -04 speed grade) | 20 MHz | 20 MHz (4 MHz @ -04 speed grade) | 20 MHz (4 MHz @ -04 speed grade) |
| RAM | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 368 bytes | 368 bytes |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 22 |
| A/D Converter | 8-bit | 8-bit | 8-bit | 8-bit | 8-bit | 8-bit |
| Memory Type | OTP (one-time-programmable) | Flash (reprogrammable) | OTP | OTP | OTP | OTP |
| Lifecycle Status | Last-Time-Buy | Active | Last-Time-Buy | Last-Time-Buy | Last-Time-Buy | Last-Time-Buy |
Key Differentiators
- Officially recommended migration path with same footprint (vs PIC16F74-I/PT)
- Faster speed grade variant available in same package (vs PIC16C74A-20I/PT)
- Larger-memory PIC16C77 family member for code growth (vs PIC16C77-04I/PT)
Design Notes
Place decoupling capacitors (100 nF ceramic + 10 uF bulk) within 5 mm of the VDD pins (11 and 41) and connect VSS pins (10 and 40) directly to a ground plane. The 44-TQFP has split power pins (two VDD and two VSS) - both must be bypassed even if the device draws relatively low current. Use short, wide traces for analog reference inputs (RA2/VREF-, RA3/VREF+) and keep them away from the oscillator traces (OSC1, OSC2) to minimize coupled noise into the 8-bit ADC.
Do not confuse the 44-TQFP (PT) package with the 40-PDIP (P) package - they share the same silicon but the pinouts differ in pin count. The /PT has 4 additional pins for extra I/O on port D/E and split power pins; substituting a /P for /PT or vice versa will short power pins. Also note that the 'I' industrial temperature suffix differs from the 'E' extended range - verify the temperature range against your operating environment before ordering. OTP memory cannot be erased, so always verify firmware with a flash-equivalent (PIC16F74) before committing to OTP programming.
The PIC16C74A-04I/PT operates from a single 5 V supply with a typical supply current of less than 2 mA at 4 MHz in active mode. For battery-backed designs, the device supports a low-power SLEEP mode that reduces current to microampere levels with the watchdog timer disabled. Add a 10 kohm pull-up on MCLR to prevent unintended resets, and ensure the in-circuit serial programming (ICSP) pins RB6/PGC and RB7/PGD are accessible on the PCB if field updates are anticipated (note: OTP memory still requires a programming adapter, not field-updateable).
Compliance Information
RoHS, REACH, lead-free and halogen-free status not stated in the verified web data; consult Microchip product page or manufacturer datasheet for confirmation. Not AEC-Q100 qualified - this part is targeted at industrial and consumer applications, not automotive. Conflict-minerals compliance statement is published by Microchip Technology for their product families.