PIC16C74A-10I/L - 8-Bit 10MHz OTP MCU 7KB | 44-PLCC | Microchip
MPN: PIC16C74A-10I/L ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.24 | $9.24 |
| 10 | $8.5 | $85.00 |
| 100 | $7.65 | $765.00 |
| 500 | $6.92 | $3,460.00 |
| 1,000 | $6.1 | $6,100.00 |
PIC16C74A-10I/L Overview
What is an 8-bit OTP microcontroller? An OTP MCU integrates a CPU core, program memory (one-time-programmable EPROM that can be written once), RAM, peripherals, and I/O into a single chip. Within the broader hierarchy, the PIC16C74A belongs to: microcontroller -> embedded MCU -> 8-bit MCU -> CMOS RISC MCU -> PIC16C7X mid-range family -> Microchip PIC16 family -> Microchip 8-bit portfolio -> semiconductor. The 8-bit RISC architecture with 35 single-word instructions enables compact, deterministic code execution ideal for real-time control.
Key features include 7KB (4K x 14) OTP program memory, 192 bytes of data RAM, 33 I/O pins with individual direction control, two CCP (Capture/Compare/PWM) modules, a watchdog timer with its own on-chip RC oscillator, power-on reset, brown-out detection, and an in-circuit serial programming (ICSP) interface. The 44-PLCC package provides a robust through-hole-mount form factor with a J-lead footprint.
The PIC16C74A uses a Harvard architecture with separate program and data buses, allowing instruction fetch and operand access in a single cycle (except program branches). At 10 MHz the instruction cycle is 100 ns, and most instructions complete in one cycle, yielding up to 10 MIPS throughput for real-time control loops. The integrated 8-bit ADC provides 8 input channels with selectable reference voltage.
Typical applications include industrial automation controllers, motor control (stepper and DC brushed), automotive body electronics (note: not AEC-Q100 qualified), HVAC control boards, security and fire-alarm panels, and embedded sensor-interface nodes. The 33 I/O and integrated ADC suit applications that previously required external logic or multiple ICs.
Design consideration: The OTP memory means code cannot be erased; for prototyping, consider the PIC16F74 (Flash) or PIC16C74B-20I/L (UV-erasable CERDIP windowed). Brown-out detect must be enabled for reliable operation in noisy industrial environments; the watchdog timer should be enabled for safety-critical applications.
This page synthesizes distributor pricing, same-package drop-in alternatives, and practical design notes not found in the bare manufacturer datasheet, providing a single engineering reference for the PIC16C74A-10I/L.
Drop-in alternatives for PIC16C74A-10I/L — 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-10I/L (same form factor and footprint) — differing in Core Architecture, Package, Timers, A/D Converter, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C74A-10I/L
✅ Drop-In✓ In Stock
$6.1 / Unit
View Datasheet →PIC16C74A-10/L
✅ Drop-In✓ In Stock
$8.4 / Unit
View Datasheet →PIC16C74A-10E/L
✅ Drop-In✓ In Stock
$7.95 / Unit
View Datasheet →PIC16C74A-10/P
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →PIC16C74A-04I/P
✅ Drop-In✓ In Stock
$7.5 / Unit
View Datasheet →PIC16C74A-04/PQ
✅ Drop-In✓ In Stock
$5.8 / Unit
View Datasheet →PIC16C74B-20I/L
✅ Drop-In✓ In Stock
$8.92 / Unit
View Datasheet →PIC16C74A-10I/L Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC RISC, Harvard |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 7 KB (4K x 14 words) |
| Data RAM | 192 bytes |
| Data EEPROM | None |
| Maximum Clock Frequency | 10 MHz |
| Instruction Cycle Time | 100 ns at 10 MHz |
| Throughput | 10 MIPS peak |
| Supply Voltage (VDD) | 4.0 V to 5.5 V |
| Number of I/O Pins | 33 |
| ADC | 8-bit, 8 channels |
| Timers | Timer0 (8-bit), Timer1 (16-bit), Timer2 (8-bit) |
| CCP Modules | 2 (Capture/Compare/PWM) |
| Serial Interfaces | USART (async/sync), SSP (SPI/I2C) |
| Operating Temperature Range | -40C to +85C (industrial, /L suffix windowed ceramic) |
| Package | 44-pin PLCC (J-Lead, 16.59 x 16.59 mm) |
| Watchdog Timer | Yes, with dedicated on-chip RC oscillator |
| Brown-out Reset | Yes |
| In-Circuit Programming | ICSP supported |
PIC16C74A-10I/L Pin Configuration
| Pin 1 | OSC1/CLKIN — Crystal oscillator input / external clock input |
| Pin 2 | OSC2/CLKOUT — Crystal oscillator output / clock output (Fosc/4) |
| Pin 3 | MCLR/VPP — Master Clear (reset) input / programming voltage |
| Pin 4 | RA0/AN0 — Port A bit 0 / analog input 0 |
| Pin 5 | RA1/AN1 — Port A bit 1 / analog input 1 |
| Pin 6 | RA2/AN2 — Port A bit 2 / analog input 2 |
| Pin 7 | RA3/AN3/VREF — Port A bit 3 / analog input 3 / ADC reference |
| Pin 8 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Pin 9 | RA5/AN4/SS — Port A bit 5 / analog input 4 / SPI slave select |
| Pin 10 | VSS — Ground |
| Pin 11 | VDD — Positive supply (4.0-5.5V) |
| Pin 12 | RB0/INT — Port B bit 0 / external interrupt |
| Pin 13 | RB1 — Port B bit 1 |
| Pin 14 | RB2 — Port B bit 2 |
| Pin 15 | RB3 — Port B bit 3 |
| Pin 16 | RB4 — Port B bit 4 |
| Pin 17 | RB5 — Port B bit 5 |
| Pin 18 | RB6/PGC — Port B bit 6 / ICSP clock |
| Pin 19 | RB7/PGD — Port B bit 7 / ICSP data |
| Pin 20 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator output / clock input |
| Pin 21 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator input / CCP2 |
| Pin 22 | RC2/CCP1 — Port C bit 2 / CCP1 |
| Pin 23 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 24 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 25 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 26 | RC6/TX/CK — Port C bit 6 / USART TX / clock |
| Pin 27 | RC7/RX/DT — Port C bit 7 / USART RX / data |
| Pin 28 | RD0/PSP0 — Port D bit 0 / parallel slave port bit 0 |
| Pin 29 | RD1/PSP1 — Port D bit 1 / PSP bit 1 |
| Pin 30 | RD2/PSP2 — Port D bit 2 / PSP bit 2 |
| Pin 31 | RD3/PSP3 — Port D bit 3 / PSP bit 3 |
| Pin 32 | RD4/PSP4 — Port D bit 4 / PSP bit 4 |
| Pin 33 | RD5/PSP5 — Port D bit 5 / PSP bit 5 |
| Pin 34 | RD6/PSP6 — Port D bit 6 / PSP bit 6 |
| Pin 35 | RD7/PSP7 — Port D bit 7 / PSP bit 7 |
| Pin 36 | RE0/RD — Port E bit 0 / parallel slave port read control |
| Pin 37 | RE1/WR — Port E bit 1 / parallel slave port write control |
| Pin 38 | RE2/CS — Port E bit 2 / parallel slave port chip select |
| Pin 39 | AVSS — Analog ground |
| Pin 40 | AVDD — Analog positive supply |
| Pin 41 | AN5 — Analog input 5 |
| Pin 42 | AN6 — Analog input 6 |
| Pin 43 | AN7 — Analog input 7 |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C74A-10I/L is suitable for 6 applications: Industrial Automation Controllers, Motor Control - DC Brushed and Stepper, HVAC and Building Automation Control Boards, Security and Fire Alarm Panels, Automotive Body Electronics (Non-Safety), Embedded Sensor Interface / Data Acquisition Nodes.
Industrial Automation Controllers
The PIC16C74A-10I/L's 33 I/O pins, 8-channel 8-bit ADC, and 10 MIPS throughput make it well suited to industrial PLC-style controllers handling sensor inputs and actuator outputs. The integrated ADC captures analog process variables (temperature via thermistor, pressure, flow) while two CCP modules generate PWM outputs for proportional valves or motor speed control. Its 4-5.5V operation aligns with the standard 5V industrial backplane, and brown-out reset plus watchdog timer protect against supply glitches in factory-floor environments. PIC16C7X architecture is widely documented, reducing engineering training overhead.
Recommended
Motor Control - DC Brushed and Stepper
The PIC16C74A-10I/L's two CCP modules can drive two brushed DC motors or one bipolar stepper in full-step or microstepping mode via external H-bridge drivers. The 10 MIPS throughput supports closed-loop PID at sample rates up to 100 kHz when paired with hardware timers, and the 8-channel ADC reads back current-sense amplifiers for torque control. Industrial-grade -40C to +85C operation suits motor enclosures. Note: the OTP memory requires full in-system programming per board, so production programming fixtures must be designed.
Recommended
HVAC and Building Automation Control Boards
The PIC16C74A-10I/L is widely deployed in HVAC control boards driving 24VAC contactors via triac interfaces and reading thermistor temperature sensors via its 8-channel ADC. The 33 I/O support multiple zone damper control, fan-speed relay outputs, and a keypad/display interface. USART enables connection to building automation modems or RS-485 transceivers for BACnet/Modbus gateway functionality. Its industrial temperature range tolerates attic and equipment-room conditions.
Recommended
Security and Fire Alarm Panels
The PIC16C74A-10I/L's integrated ADC, USART, and 33 I/O accommodate multi-zone intrusion or fire-alarm panels that monitor loops of smoke detectors, PIR sensors, and magnetic contacts. The hardware watchdog timer (with its own on-chip RC) ensures the system resets on firmware lockup, a critical safety requirement. Brown-out reset maintains state during brownouts. The 192-byte RAM and 7KB OTP accommodate small zone-count firmware with keypad menus and dialer/cellular modem interface via USART.
Recommended
Automotive Body Electronics (Non-Safety)
The PIC16C74A-10I/L appears in non-safety automotive body electronics such as interior lighting controllers, seat-position memory modules, and aftermarket gauge clusters. Its 5V operation interfaces directly to automotive 12V via 7805 regulators. Note: this part is NOT AEC-Q100 qualified and Microchip recommends PIC16F74 or PIC18 equivalents for new automotive designs. The 33 I/O and PWM outputs suit multi-channel LED dimming and gauge stepper driving.
Recommended
Embedded Sensor Interface / Data Acquisition Nodes
The PIC16C74A-10I/L's 8-channel 8-bit ADC and SSP (SPI/I2C) make it suitable as a low-cost sensor hub that aggregates thermocouple, RTD, or strain-gauge signals and reports them over USART to a host controller. At 10 MIPS it can perform basic linearization and filtering in firmware. The 33 I/O and modest RAM let it service 8 analog inputs plus digital status I/O simultaneously. Industrial -40 to +85C operation allows outdoor or cabinet-mounted sensor nodes.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C74A-10I/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C74A-10/L | PIC16C74A-10E/L | PIC16C74B-20I/L | PIC16C74A-04I/P |
|---|---|---|---|---|---|
| Package | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Clock Frequency | 10 MHz | 10 MHz | 10 MHz | 20 MHz | 4 MHz |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB UV EPROM | 7 KB OTP |
| Data RAM | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes |
| Temperature Range | -40C to +85C (industrial) | 0C to +70C (commercial) | -40C to +125C (extended) | -40C to +85C (industrial) | -40C to +85C (industrial) |
| Memory Type | OTP EPROM (one-time) | OTP EPROM | OTP EPROM | UV-erasable CERDIP windowed | OTP EPROM |
| ADC Channels / Bits | 8 / 8-bit | 8 / 8-bit | 8 / 8-bit | 8 / 8-bit | 8 / 8-bit |
| I/O Pins | 33 | 33 | 33 | 33 | 33 |
| AEC-Q100 Qualified | No | No | No | No | No |
Key Differentiators
- Same-family industrial drop-in availability (vs PIC16C74A-10/L)
- 2x clock headroom on B variant (vs PIC16C74B-20I/L)
- Higher temperature ceiling on /E variant (vs PIC16C74A-10E/L)
Design Notes
The PIC16C74A-10I/L requires a stable 4.0V to 5.5V supply with brown-out detection enabled. Place a 100 nF ceramic decoupling capacitor within 5 mm of the VDD/AVDD pins and a 10 uF bulk tantalum or aluminum polymer capacitor at the regulator output. For analog accuracy, separate analog VDD (AVDD) and analog VSS (AVSS) supplies are provided; route AVSS to a quiet ground star-point and add a ferrite bead between VDD and AVDD to reduce digital switching noise on the ADC reference.
OTP memory can be programmed only once per chip; there is no in-system field update path. Plan production programming fixtures (gang programmers, ICSP fixtures, or third-party programming houses) accordingly. Brown-out reset must be configured via the configuration bits (BODEN) and a valid BOR voltage threshold (BORV) - failure to enable brown-out reset can cause undefined execution during supply droop, especially in industrial environments with large inductive loads on the same 24V bus.
The 44-PLCC J-lead package requires a PLCC socket for development (e.g., 44-pin DIP-to-PLCC adapter) and a careful PCB land pattern: 1.27 mm (50 mil) pitch J-leads with a center pad for mechanical stability. Keep analog traces (RA0-RA5, AN5-AN7) away from switching signals like OSC1/OSC2 and CCP1/CCP2 PWM outputs; route analog ground AVSS as a separate island joining VSS only at the regulator. The MCLR pin requires a 10 kohm pull-up to VDD and a 100 nF cap to ground for reset integrity.
When driving the ADC from high-impedance sensors, add a 100 pF to 1 nF ceramic capacitor on each analog input to filter RF and to provide the ADC sample-and-hold charge reservoir. Acquisition time for the 8-bit ADC at 10 MHz is short, but source impedance above 5 kohm degrades accuracy. Use the VREF+ pin (shared with RA3) tied to a stable external reference (e.g., MCP1541) when absolute accuracy matters more than ratiometric measurements against VDD.
Compliance Information
The /L windowed ceramic PLCC package is generally non-RoHS due to lead-bearing terminations and ceramic body. Microchip recommends PIC16F74 (Flash, RoHS, plastic PLCC) for new designs. Part is not AEC-Q100 qualified - for automotive use, consider PIC16F74T-I/PT or PIC18F equivalent.
