PIC16C74B-04E/L - 8-bit OTP MCU 4MHz 7KB 44-PLCC | Microchip
MPN: PIC16C74B-04E/L β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.5 | $14.50 |
| 10 | $13.05 | $130.50 |
| 100 | $11.6 | $1,160.00 |
| 500 | $10.45 | $5,225.00 |
| 1,000 | $9.3 | $9,300.00 |
PIC16C74B-04E/L Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, non-volatile program memory, and peripherals on one die. The PIC16C family sits within Microchip's mid-range MCU hierarchy: PIC10/12/16 baseline -> PIC16C mid-range -> PIC18/dsPIC enhanced -> 32-bit Cortex-M class. Mid-range MCUs target embedded control tasks that need deterministic timing, simple peripheral sets, and code density better than 8-bit baselines without the cost of a 32-bit core.
Key features include 33 digital I/O lines, 8 channels of 8-bit Analog-to-Digital conversion, two 8-bit timers plus one 16-bit timer, two Capture/Compare/PWM (CCP) peripherals, a synchronous serial port configurable as SPI or I2C, and a Universal Synchronous/Asynchronous Receiver-Transmitter (USART). High sink/source current of 25 mA per pin simplifies direct drive of LEDs and small relays. Wide operating voltage spans 2.5 V to 6.0 V with typical standby current of 1 uA at 3 V / 32 kHz.
Typical applications include industrial control panels, automotive body electronics, sensor signal conditioning, and embedded instrumentation where the extended temperature range and OTP-based code security are required. The PIC16C74B is also a drop-in successor to PIC16C74A variants in the same 44-pin PLCC footprint, offering a clear migration path within Microchip's mid-range portfolio.
Drop-in alternatives for PIC16C74B-04E/L 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 PIC16C74B-04E/L (same form factor and footprint) β differing in Core Architecture, Operating Temperature, Program Memory Size, Serial Interfaces, RAM Size.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C74B-04/L
β Drop-Inπ Reference alternative (not in catalog)
PIC16C74B-04I/L
β Drop-Inβ In Stock
$2.61 / Unit
View Datasheet βPIC16C74B-20/L
β Drop-Inβ In Stock
$8.2 / Unit
View Datasheet βPIC16F74-I/L
β Drop-Inπ Reference alternative (not in catalog)
PIC16C74A-04/L
β Drop-Inπ Reference alternative (not in catalog)
PIC16C74B-04E/L Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16CXX mid-range 8-bit RISC |
| Program Memory | 7 KB (4K x 14) OTP |
| RAM Size | 192 x 8 bytes |
| Maximum Clock Frequency | 4 MHz |
| Instruction Execution Time | 200 ns at 20 MHz |
| Instruction Set Size | 35 single-word instructions |
| Number of I/O Pins | 33 |
| ADC | 8 channels, 8-bit resolution |
| Timers | 2 x 8-bit + 1 x 16-bit |
| Capture/Compare/PWM | 2 CCP modules |
| Serial Interfaces | SPI, I2C, USART |
| Operating Voltage Range | 2.5 V to 6.0 V |
| DC Source/Sink Current per I/O | 25 mA / 25 mA |
| Typical Standby Current | 1 uA at 3 V, 32 kHz |
| Operating Temperature | -40C to +125C (Extended, grade E) |
| Package | 44-pin PLCC (J-Lead, L) |
| Package Dimensions | 16.59 mm x 16.59 mm |
| Mounting Type | Surface Mount |
| Lead-Free / RoHS | Lead-containing (non-RoHS by default for OTP C parts) |
PIC16C74B-04E/L Pin Configuration
| Pin 1 | MCLR/VPP β Master Clear (Reset) input / Programming voltage |
| Pin 2 | RA0/AN0 β PORTA bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 β PORTA bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2 β PORTA bit 2 / Analog input 2 |
| Pin 5 | RA3/AN3/VREF β PORTA bit 3 / Analog input 3 / VREF+ |
| Pin 6 | RA4/T0CKI β PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS β PORTA bit 5 / Analog input 4 / SPI Slave Select |
| Pin 8 | RE0/RD β PORTE bit 0 / Read control for parallel slave port |
| Pin 9 | RE1/WR β PORTE bit 1 / Write control for parallel slave port |
| Pin 10 | RE2/CS β PORTE bit 2 / Chip select for parallel slave port |
| Pin 11 | VDD β Positive supply (5 V nominal) |
| Pin 12 | VSS β Ground reference |
| Pin 13 | OSC1/CLKIN β Oscillator crystal input / external clock input |
| Pin 14 | OSC2/CLKOUT β Oscillator crystal output / clock out (Fosc/4) |
| Pin 15 | RC0/T1OSO/T1CKI β PORTC bit 0 / Timer1 oscillator out / clock in |
| Pin 16 | RC1/T1OSI/CCP2 β PORTC bit 1 / Timer1 oscillator in / CCP2 |
| Pin 17 | RC2/CCP1 β PORTC bit 2 / Capture/Compare/PWM 1 |
| Pin 18 | RC3/SCK/SCL β PORTC bit 3 / SPI clock / I2C clock |
| Pin 19 | RD0/PSP0 β PORTD bit 0 / Parallel slave port data bit 0 |
| Pin 20 | RD1/PSP1 β PORTD bit 1 / Parallel slave port data bit 1 |
| Pin 21 | RD2/PSP2 β PORTD bit 2 / Parallel slave port data bit 2 |
| Pin 22 | RD3/PSP3 β PORTD bit 3 / Parallel slave port data bit 3 |
| Pin 23 | RC4/SDI/SDA β PORTC bit 4 / SPI data in / I2C data |
| Pin 24 | RC5/SDO β PORTC bit 5 / SPI data out |
| Pin 25 | RC6/TX/CK β PORTC bit 6 / USART TX / clock (sync mode) |
| Pin 26 | RC7/RX/DT β PORTC bit 7 / USART RX / data (sync mode) |
| Pin 27 | RD4/PSP4 β PORTD bit 4 / Parallel slave port data bit 4 |
| Pin 28 | RD5/PSP5 β PORTD bit 5 / Parallel slave port data bit 5 |
| Pin 29 | RD6/PSP6 β PORTD bit 6 / Parallel slave port data bit 6 |
| Pin 30 | RD7/PSP7 β PORTD bit 7 / Parallel slave port data bit 7 |
| Pin 31 | VSS β Ground reference |
| Pin 32 | VDD β Positive supply (5 V nominal) |
| Pin 33 | RB0/INT β PORTB bit 0 / External interrupt input |
| Pin 34 | RB1 β PORTB bit 1 |
| Pin 35 | RB2 β PORTB bit 2 |
| Pin 36 | RB3 β PORTB bit 3 |
| Pin 37 | RB4 β PORTB bit 4 |
| Pin 38 | RB5 β PORTB bit 5 |
| Pin 39 | RB6/PGC β PORTB bit 6 / ICSP clock (programming/debug) |
| Pin 40 | RB7/PGD β PORTB bit 7 / ICSP data (programming/debug) |
| Pin 41 | NC β Not connected (per datasheet) |
| Pin 42 | NC β Not connected (per datasheet) |
| Pin 43 | NC β Not connected (per datasheet) |
| Pin 44 | NC β Not connected (per datasheet) |
Typical Applications
PIC16C74B-04E/L is suitable for 6 applications: Industrial Process Control, Automotive Body Electronics, Embedded Sensor Signal Conditioning, White Goods and Home Appliance Control, Test and Measurement Instrumentation, Security and Access Control Panels.
Industrial Process Control
The PIC16C74B-04E/L fits industrial process controllers thanks to its 8-channel 8-bit ADC for analog sensor inputs (4-20 mA, 0-10 V, thermocouple pre-amp outputs), 33 digital I/O for valve/relay drivers, and the 25 mA sink/source capability that eliminates external transistors. The extended -40C to +125C temperature grade handles unconditioned cabinet environments, while 192 bytes of RAM and 7 KB OTP cover typical PID control loops. Placed on a backplane with optoisolated I/O, it executes a 200 ns instruction cycle at 4 MHz fast enough for sub-millisecond loop times, and the USART links directly to an RS-485 transceiver for SCADA networks.
Recommended
Automotive Body Electronics
The PIC16C74B-04E/L's extended -40C to +125C temperature grade and OTP code security make it a fit for automotive body modules such as climate controls, lighting timers, and seat controllers. The two CCP peripherals drive PWM outputs for LED dimming and motor speed, the USART interfaces with body control network gateways, and the 25 mA I/O drive small relays directly. Code is locked in OTP after verification, reducing the risk of field firmware tampering. Placed on a switch-mode supply input and connected via I2C to sensor clusters, it replaces larger discrete logic with deterministic mid-range PIC performance.
Recommended
Embedded Sensor Signal Conditioning
Multi-channel sensor conditioning benefits from the PIC16C74B-04E/L's 8-channel 8-bit ADC scanning rate (around 15 ksps combined) and on-chip 16-bit Timer1 for precise sampling windows. The 7 KB OTP holds scaling, calibration and linearization tables for thermocouples, RTDs and strain gauges. The master SPI/I2C port reads digital sensors or drives an external DAC/ADC for higher-precision front ends. Mounted on a 4-layer sensor board with the MCU in 44-PLCC, designers gain an 8-bit deterministic engine that is reproducible and tamper-resistant for OEM instruments.
Recommended
White Goods and Home Appliance Control
Washing machine, dishwasher and HVAC control boards use the PIC16C74B-04E/L to manage triac-driven loads, keypad inputs, and alphanumeric LCDs. The CCP PWM outputs dim indicators and drive variable-speed pumps, while the 33 I/O scan the keypad matrix without external muxes. OTP program memory locks the certified control algorithm, preventing field tampering with safety-critical parameters. Connected to a triac opto-coupler interface and protected by the wide 2.5-6.0 V supply range, the PIC16C74B-04E/L operates reliably from rectified mains-rail rails with minimal external regulation.
Recommended
Test and Measurement Instrumentation
Bench instruments and portable dataloggers use the PIC16C74B-04E/L as a measurement co-processor: the 8-bit ADC captures multiplexed analog inputs while the USART streams data to a host PC or display. The 35-instruction mid-range core runs deterministic state machines with sub-microsecond latency, ideal for waveform-edge detection via the CCP capture inputs. OTP code security protects proprietary calibration constants stored in non-volatile memory. Paired with an external 16-bit ADC for high-precision channels, it forms a compact front end for hand-held multimeters.
Recommended
Security and Access Control Panels
Alarm panels and access controllers use the PIC16C74B-04E/L for keypad scanning, sensor loop monitoring, and dialer output via the USART. The 33 I/O handle multiple zones directly, while the 16-bit Timer1 keeps wall-clock time with a 32.768 kHz crystal. OTP memory locks installer codes and event logs, resisting tamper attempts. Placed in a wall-mounted enclosure with battery backup, the PIC16C74B-04E/L extends battery life through its 1 uA typical standby current at 3 V / 32 kHz, meeting the multi-year standby requirement of UL-listed alarm panels.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C74B-04E/L β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C74B-04/L | PIC16C74B-04I/L | PIC16C74B-20/L | PIC16F74-I/L | PIC16C74A-04/L |
|---|---|---|---|---|---|---|
| Package | 44-PLCC (J-Lead, 16.59x16.59 mm) | 44-PLCC (J-Lead) - same | 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 - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same |
| Program Memory | 7 KB (4K x 14) OTP | 7 KB OTP - same | 7 KB OTP - same | 7 KB OTP - same | 7 KB Flash | 7 KB OTP - same |
| Maximum Clock Speed | 4 MHz | 4 MHz | 4 MHz | 20 MHz (5x faster) | 20 MHz | 4 MHz |
| RAM Size | 192 x 8 bytes | 192 bytes - same | 192 bytes - same | 192 bytes - same | 192 bytes - same | 192 bytes - same |
| Temperature Grade | Extended (-40C to +125C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) |
| ADC | 8-channel 8-bit | 8-channel 8-bit - same | 8-channel 8-bit - same | 8-channel 8-bit - same | 8-channel 8-bit - same | 8-channel 8-bit - same |
| Serial Interfaces | USART + SPI/I2C | USART + SPI/I2C - same | USART + SPI/I2C - same | USART + SPI/I2C - same | USART + SPI/I2C - same | USART + SPI/I2C - same |
| Memory Type | OTP (one-time-program) | OTP - same | OTP - same | OTP - same | Flash (re-programmable) | OTP - same |
Key Differentiators
- Extended temperature grade (-40C to +125C) (vs PIC16C74B-04/L)
- OTP code security for certified/production code (vs PIC16F74-I/L)
- 8-channel 8-bit ADC integrated with CCP/USART (vs PIC16C73B-04/SP (28-pin variant))
Design Notes
Place a 0.1 uF ceramic decoupling capacitor within 5 mm of each VDD/VSS pin pair (pins 11/12 and 32/31 on the 44-PLCC). For wide-temperature boards add a 10 uF tantalum bulk cap on the main 5 V rail. Estimated: total supply current at 4 MHz / 5 V is 5-15 mA across the digital + ADC + peripherals, well within the recommended VDD source capability.
Keep the analog inputs (RA0-RA5) traces short and guarded by a ground plane to minimize ADC crosstalk with digital switching noise. Place the crystal at pins 13/14 within 10 mm of the MCU and surround it with a guard trace tied to VSS; per the PIC16C74B datasheet, long oscillator traces cause frequency drift and ADC conversion errors. NC pins (41-44) should be left floating per Microchip application notes.
PIC16C74B is OTP - once programmed it cannot be cleared. Therefore always validate firmware on a PIC16F74-I/L (Flash equivalent, same 44-PLCC footprint) before committing production code. Ensure ICSP programming lines PGC/PGD (RB6/RB7, pins 39/40) have no series resistors >470 ohm; larger values will violate the In-Circuit Serial Programming timing. Estimated: programming pulse rise time must be <50 ns to pass Microchip spec.
Compliance Information
The Microchip PIC16C family OTP C-parts are typically leaded (SnPb) and are flagged as non-RoHS by default; check the device marking or factory documentation for specific lead-free variants. AEC-Q100 automotive qualification has not been obtained - use PIC16C74B-04E/Q or PIC18F equivalent for AEC-Q100 requirements.
