PIC16C72A-20I/SO - 8-Bit 20MHz OTP MCU 3.5KB 28-SOIC | Microchip
MPN: PIC16C72A-20I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.95 | $8.95 |
| 10 | $8.2 | $82.00 |
| 100 | $7.45 | $745.00 |
| 500 | $6.8 | $3,400.00 |
| 1,000 | $6.15 | $6,150.00 |
PIC16C72A-20I/SO Overview
An 8-bit PIC microcontroller is a RISC (Reduced Instruction Set Computer) device built around a Harvard architecture with separate program and data buses, executing one instruction per instruction cycle (4 clock cycles). The PIC16C family uses CMOS technology with OTP or EPROM program memory, distinguished from the flash-based PIC16F family by being one-time-programmable, which makes them common in cost-sensitive production runs where code is finalized at volume. The PIC16C72A sits in the mid-range tier, offering 35 single-word instructions, 8-level hardware stack, and 200 ns instruction execution time, providing a balance of capability and code density for embedded control.
Key features include 5 channels of 8-bit A/D (suitable for sensor interfacing), 22 individually-direction-controlled I/O pins, a 16-bit Timer1 with prescaler and external crystal sleep-mode increment capability, and an SSP module that supports both SPI master/slave and I2C master/slave protocols. The part operates from 3.0 V to 5.5 V and includes power-managed modes such as Sleep with wake-up on interrupt, plus a Watchdog Timer with its own on-chip RC oscillator for reliable operation without external supervision.
Architecturally, the PIC16C72A uses a RISC core with 14-bit instruction words, an 8-bit data path, and dedicated peripheral modules mapped into the SFR space. The 8-bit A/D converter is successive-approximation type with acquisition time controlled by software, sufficient for slow-changing analog signals such as temperature, light, or position feedback. The CCP module supports capture (for timing measurement), compare (for timed output events), and PWM (for motor, LED, or audio frequency generation), making the device a versatile single-chip solution.
Typical applications include industrial control panels, appliance control boards, sensor interface modules, low-end motor control, LED lighting controllers, and battery-powered instrumentation where the OTP memory model and 5V operation simplify BOM and supply design. The wide 28-SOIC footprint also makes it breadboard-friendly for prototype and educational use, and the broad base of legacy PIC16 code enables rapid porting from PIC16C7X designs.
When designing with the PIC16C72A-20I/SO, ensure that the oscillator configuration (RC, XT, HS, or LP) is selected in the configuration word to match the external clock source, and that the A/D converter's reference voltage is stable - the 5V supply can be used as Vref when accuracy requirements are modest. Because OTP memory cannot be reprogrammed, prototypes should be developed on a flash-based equivalent (such as the PIC16F72 or PIC16F73) and the final code only burned into the PIC16C72A in production.
This page synthesizes distributor pricing, drop-in alternative MPNs, pinout data, and practical design notes that go beyond the manufacturer datasheet, giving engineers a single reference for sourcing and designing with the PIC16C72A-20I/SO.
Drop-in alternatives for PIC16C72A-20I/SO — 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 PIC16C72A-20I/SO (same form factor and footprint) — differing in Package, Timers, Operating Temperature, ADC, Core.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C72A-20/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C72A-20I/ML
✅ Drop-In✓ In Stock
$3.1 / Unit
View Datasheet →PIC16C72-20I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C72-20/SO
✅ Drop-In✓ In Stock
$3.78 / Unit
View Datasheet →PIC16C72-10I/SO
✅ Drop-In✓ In Stock
$4.25 / Unit
View Datasheet →PIC16C72-04I/SO
✅ Drop-In✓ In Stock
$4.71 / Unit
View Datasheet →PIC16F72-I/SO
✅ Drop-In✓ In Stock
$1.95 / Unit
View Datasheet →PIC16C72A-20I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 3.5 KB (2K x 14) |
| RAM Size | 128 x 8 bytes |
| Maximum CPU Frequency | 20 MHz |
| Instruction Execution Time | 200 ns |
| Number of I/O Pins | 22 |
| A/D Converter | 5 channels x 8-bit |
| Timers | Timer0 (8-bit), Timer1 (16-bit), Timer2 (8-bit PWM) |
| Capture/Compare/PWM | 1 CCP module |
| Serial Communication | SSP (SPI or I2C) |
| Supply Voltage | 3.0 V to 5.5 V |
| Operating Temperature | -40C to +85C (Industrial) |
| Package | 28-pin SOIC (SO) |
| Mounting Type | Surface Mount |
| Number of Instructions | 35 single-word |
| Watchdog Timer | Yes, with on-chip RC oscillator |
PIC16C72A-20I/SO Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input or programming voltage input |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / Analog input 2 |
| Pin 5 | RA3/AN3/VREF — PORTA bit 3 / Analog input 3 / A/D voltage reference |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / Analog input 4 / SPI slave select |
| Pin 8 | OSC2/CLKOUT — Oscillator output / Clock output |
| Pin 9 | OSC1/CLKIN — Oscillator input / External clock input |
| Pin 10 | VSS — Ground reference |
| Pin 11 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 12 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 output |
| Pin 13 | RC2/CCP1 — PORTC bit 2 / Capture Compare PWM 1 |
| Pin 14 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 16 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 17 | RC6 — PORTC bit 6 |
| Pin 18 | RC7 — PORTC bit 7 |
| Pin 19 | VSS — Ground reference (second) |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RB0/INT — PORTB bit 0 / External interrupt input |
| Pin 22 | RB1 — PORTB bit 1 |
| Pin 23 | RB2 — PORTB bit 2 |
| Pin 24 | RB3 — PORTB bit 3 |
| Pin 25 | RB4 — PORTB bit 4 |
| Pin 26 | RB5 — PORTB bit 5 |
| Pin 27 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 28 | RB7/PGD — PORTB bit 7 / ICSP data |
Typical Applications
PIC16C72A-20I/SO is suitable for 7 applications: Industrial Control Panels, Appliance Control Boards, Sensor Interface Modules, LED Lighting Controllers, Low-End Motor Control, Battery-Powered Instrumentation, Educational and Hobbyist Embedded Systems.
Industrial Control Panels
The PIC16C72A-20I/SO fits industrial control panel designs where its 22 I/O pins drive relay coils, LED indicators, and keypad matrix scanning while the 5-channel 8-bit A/D reads panel-mounted sensors such as thermistors, pressure transducers, and potentiometers. At 20 MHz with 200 ns instruction execution, the MCU can service a 4x4 keypad matrix with sub-10 ms debounce and a multiplexed 7-segment display refresh at 100+ Hz without CPU saturation. The industrial -40C to +85C temperature range and 3.0-5.5V supply allow direct operation from 5V industrial backplanes without level shifters. The OTP memory model is ideal for panel controllers whose code is finalized at panel commissioning and never requires field updates, keeping per-unit cost low for high-volume panel runs.
Recommended
Appliance Control Boards
The PIC16C72A-20I/SO is well-suited for washing machine, dishwasher, and oven control boards where the CCP module drives TRIAC phase-control for heating elements and the SSP runs SPI to a segmented LCD or EEPROM display. Its 5-channel A/D monitors water level, temperature, and motor current via shunt resistors, with software-decided safety thresholds. The 28-SOIC package mounts to a hand-solderable through-hole or SMT pad pattern familiar to appliance designers, and the 5V operation aligns with white-goods power rails. OTP memory locks firmware at production, preventing end-user firmware modification - a key safety and liability requirement for appliances sold globally.
Recommended
Sensor Interface Modules
For sensor interface modules in HVAC, environmental monitoring, and process control, the PIC16C72A-20I/SO provides 5 channels of 8-bit A/D sufficient to digitize multiple 0-5V analog sensors with adequate resolution for setpoint control. The SSP configured as I2C allows connection to off-chip I2C sensors (temperature, humidity, light) expanding the system beyond the 5 internal A/D channels. The 128 bytes of RAM and 3.5 KB OTP hold calibration coefficients, linearization tables, and Modbus or simple serial protocol stacks. The 28-SOIC surface-mount package suits compact sensor PCBAs, and the industrial temperature grade supports outdoor and factory-floor deployment.
Recommended
LED Lighting Controllers
The PIC16C72A-20I/SO controls RGB or white LED lighting fixtures using its CCP module for PWM dimming on one channel and software PWM on additional pins for RGB color mixing. The 20 MHz clock provides PWM frequencies above 100 kHz to avoid visible flicker, while the A/D channels read ambient light sensors and potentiometer dimmer inputs. The SSP in SPI mode can drive addressable LED strips (WS2801, APA102) for higher-end fixtures. With 22 I/O pins, a single PIC16C72A-20I/SO can manage multiple LED channels, a 7-segment display, and capacitive touch buttons without additional I/O expanders, making it a cost-effective lighting controller solution.
Recommended
Low-End Motor Control
The PIC16C72A-20I/SO drives small DC motors, stepper motors, and BLDC fans using its CCP module for PWM speed control and the 5-channel A/D for back-EMF sensing or current feedback. The 20 MHz instruction rate provides sufficient bandwidth for closed-loop PI control loops at 1-10 kHz update rates. Timer1's 16-bit range allows precise RPM measurement via tachometer pulse counting. The 5V I/O directly interfaces to optocouplers or gate drivers for safe motor isolation. The industrial temperature range supports motor control in automotive under-hood and industrial cabinet environments, while the OTP memory model is appropriate for fixed-curve motor controllers where the speed profile is finalized at design time.
Recommended
Battery-Powered Instrumentation
The PIC16C72A-20I/SO with its low-power Sleep mode (microamp range) and wake-on-interrupt capability is a fit for battery-powered data loggers, handheld meters, and portable test instruments. The A/D channels digitize battery voltage, sensor signals, and reference voltages for accurate measurement, while the SSP in I2C mode connects to external EEPROM (24LC256) for non-volatile data storage. The Watchdog Timer with its own RC oscillator ensures the instrument recovers from software faults without draining the battery. Industrial -40 to +85C operation supports field deployment in outdoor and cold-storage environments, and the 28-SOIC PCB-friendly package suits hand-held device form factors.
Recommended
Educational and Hobbyist Embedded Systems
The PIC16C72A-20I/SO is widely used in university embedded systems courses and hobbyist projects because the 28-SOIC or PDIP (SP variant) package is breadboard-friendly and the 5V operation tolerates a wide range of 5V-tolerance peripherals. The PIC16C family has an extensive library of open-source example code, application notes, and community tutorials, making it accessible for students learning RISC architecture, A/D conversion, PWM, and serial protocols. The 35 single-word instruction set is small enough to learn in a semester, and the 8-level hardware stack is straightforward to debug without complex RTOS considerations. The 5-channel A/D, CCP PWM, and SPI/I2C peripherals cover the typical student project requirements from sensor reading to actuator control.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C72A-20I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C72A-20/SO | PIC16C72A-20I/ML | PIC16C72-20I/SO | PIC16C72-10I/SO | PIC16F72-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (SO) | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same |
| Program Memory | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB Flash |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 10 MHz | 20 MHz |
| Temperature Grade | Industrial -40C to +85C | Commercial 0C to +70C | Industrial -40C to +85C | Industrial -40C to +85C | Industrial -40C to +85C | Industrial -40C to +85C |
| A/D Converter | 5 channels x 8-bit | 5 channels x 8-bit | 5 channels x 8-bit | 5 channels x 8-bit | 5 channels x 8-bit | 5 channels x 8-bit |
| RAM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes |
| Memory Type | OTP | OTP | OTP | OTP | OTP | Flash (reprogrammable) |
Key Differentiators
- Industrial temperature grade in 28-SOIC package (vs PIC16C72A-20/SO)
- Flash memory for development and field updates (vs PIC16C72-20I/SO)
- Full 20 MHz speed grade (vs PIC16C72-10I/SO)
Design Notes
The PIC16C72A uses OTP (one-time-programmable) memory, so any programming error or code bug discovered after programming requires discarding the part. For development, use a flash-based equivalent (PIC16F72-I/SO or PIC16F73-I/SO) and only switch to PIC16C72A for production runs. Also confirm the configuration word (oscillator type, Watchdog enable, code protection bits) is set correctly before programming, as OTP mistakes cannot be corrected with a chip erase.
Place a 100 nF decoupling capacitor as close as possible to the VDD pin (pin 20) and a 10-47 uF bulk capacitor on the same supply trace. The MCLR/VPP pin (pin 1) requires a 10 kohm pull-up resistor to VDD and a 100 nF capacitor to ground for in-circuit serial programming (ICSP) reliability. The oscillator pins (9, 10) should be kept short and surrounded by a ground pour; for crystal operation use 15-33 pF load capacitors selected per crystal manufacturer specifications.
The PIC16C72A supply range is 3.0 V to 5.5 V; for designs operating from a 3.3 V rail, verify the A/D converter's Vref+ selection is below 3.3 V. In Sleep mode, current consumption drops to microamp range with peripherals disabled - disable the A/D converter via ADON=0 and the SSP via SSPEN=0 before entering Sleep to minimize quiescent current. The Watchdog Timer can run during Sleep but draws additional current; disable WDT in firmware for lowest Sleep current in battery applications.
Compliance Information
RoHS compliance status not explicitly stated in the verified web data - mark as unknown. Lead-free is the standard for SOIC packaging at Microchip. AEC-Q100 not applicable as this is an industrial-grade (-40C to +85C) part, not automotive-grade (-40C to +125C with Q100 qualification).
