PIC16C72-20I/SP - 8-Bit 20MHz OTP MCU, 28-SPDIP | Microchip
MPN: PIC16C72-20I/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.09 | $6.09 |
| 10 | $5.48 | $54.80 |
| 100 | $4.88 | $488.00 |
| 500 | $4.39 | $2,195.00 |
| 1,000 | $3.95 | $3,950.00 |
PIC16C72-20I/SP Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory, data RAM, and peripheral interfaces on one die. The PIC16C7X family specifically targets mid-range applications requiring on-chip analog conversion and serial communication. Microcontrollers sit within the broader taxonomy of microprocessors -> embedded processors -> microcontrollers -> 8-bit MCUs, and are foundational building blocks of embedded systems.
Key differentiating features include the integrated 8-bit ADC (eliminating external converter cost), hardware USART for asynchronous serial links, brown-out reset (BOR) for reliable power-up, and a watchdog timer for fault recovery. The 128-byte RAM and 3.5 KB OTP support moderate-complexity control loops, sensor interfaces, and user-interface firmware.
Architecturally, the PIC16C72 uses a Harvard RISC core with a 14-bit instruction word, allowing most instructions to execute in a single 200 ns instruction cycle at 20 MHz. Its five ADC channels share a single sample-and-hold, with conversion completed via successive approximation. The 22 I/O pins each source/sink up to 25 mA, enabling direct LED drive without buffering.
Typical applications include industrial sensor conditioning with on-chip ADC, motor control with CCP/PWM, HVAC thermostats, appliance control boards, and simple serial-linked sensor nodes. The industrial temperature range supports factory-floor deployment where commercial-grade parts would fail.
Design tip: the OTP memory requires a device programmer to write firmware before PCB assembly; for prototype or low-volume production, choose the flash-based PIC16F72 in the same 28-SPDIP footprint as a development path that can later migrate to the OTP PIC16C72 for cost-optimized production.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives including same-family and cross-family Microchip variants, and practical design notes not consolidated in the manufacturer datasheet, giving engineers a single reference for sourcing and substitution decisions.
Drop-in alternatives for PIC16C72-20I/SP — 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 PIC16C72-20I/SP (same form factor and footprint) — differing in Package, Program Memory Type, Timers, ADC, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C72A-20I/SP
✅ Drop-In✓ In Stock
$6.2 / Unit
View Datasheet →PIC16F72-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C72-20/SP
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →PIC16C72-10I/SP
✅ Drop-In✓ In Stock
$5.2 / Unit
View Datasheet →PIC16C72-20E/SP
✅ Drop-In✓ In Stock
$5.4 / Unit
View Datasheet →PIC16C73-20I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C72-20I/SP Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC mid-range Harvard RISC |
| Instruction Set | 14-bit, 35 instructions |
| Maximum Clock Speed | 20 MHz |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 3.5 KB (2K x 14) |
| RAM Size | 128 bytes |
| EEPROM Data Memory | None |
| Digital I/O Pins | 22 |
| ADC | 8-bit, 5 channels |
| USART | 1 x hardware USART/SCI |
| CCP Modules | 1 x Capture/Compare/PWM |
| Timers | Timer0 (8-bit w/ prescaler), Timer1 (16-bit), Timer2 (8-bit w/ postscaler) |
| Watchdog Timer | Yes (independent RC oscillator) |
| Brown-Out Reset (BOR) | Yes |
| Supply Voltage | 4.0 V to 5.5 V |
| Operating Temperature Range | -40 C to +85 C (industrial) |
| I/O Sink/Source Current | 25 mA per pin |
| Package | 28-SPDIP (Skinny PDIP, 0.300 inch / 7.62 mm row spacing) |
| Mounting Type | Through-Hole (DIP) |
| MSL Level | 1 (not moisture-sensitive) |
| RoHS Status | Compliant (per Microchip product page, suffix /SP) |
PIC16C72-20I/SP Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset, active low) / programming voltage input |
| Pin 2 | RA0/AN0 — Port A bit 0 / analog input channel 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / analog input channel 1 |
| Pin 4 | RA2/AN2 — Port A bit 2 / analog input channel 2 |
| Pin 5 | RA3/AN3/VREF — Port A bit 3 / analog input channel 3 / ADC voltage reference |
| Pin 6 | RA4/T0CKI — Port A bit 4 / Timer0 clock input (open-drain) |
| Pin 7 | RA5/AN4/SS — Port A bit 5 / analog input channel 4 / SPI slave select |
| Pin 8 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 9 | OSC2/CLKOUT — Oscillator crystal output / clock output |
| Pin 10 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 11 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator input / CCP2 output |
| Pin 12 | RC2/CCP1 — Port C bit 2 / CCP1 (PWM) output |
| Pin 13 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 14 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 15 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 16 | RC6/TX/CK — Port C bit 6 / USART asynchronous transmit / I2C clock (in I2C mode) |
| Pin 17 | RC7/RX/DT — Port C bit 7 / USART asynchronous receive / I2C data (in I2C mode) |
| Pin 18 | VDD — Positive supply voltage (4.0V to 5.5V) |
| Pin 19 | VSS — Ground reference |
| Pin 20 | RB0/INT — Port B bit 0 / external interrupt input |
| Pin 21 | RB1 — Port B bit 1 |
| Pin 22 | RB2 — Port B bit 2 |
| Pin 23 | RB3/PGM — Port B bit 3 / low-voltage programming input |
| Pin 24 | RB4 — Port B bit 4 |
| Pin 25 | RB5 — Port B bit 5 |
| Pin 26 | RB6/PGC — Port B bit 6 / ICSP clock input |
| Pin 27 | RB7/PGD — Port B bit 7 / ICSP data input/output |
| Pin 28 | VDD — Positive supply voltage (4.0V to 5.5V, secondary) |
Typical Applications
PIC16C72-20I/SP is suitable for 6 applications: Industrial Sensor Interface Board, HVAC Thermostat and Control Panel, Appliance Control Board (Washer / Dishwasher), Motor Control (Small BLDC / Stepper Driver), Serial-Connected Sensor Node (RS-232/RS-485), Simple User Interface Panel (Keypad + LCD).
Industrial Sensor Interface Board
The PIC16C72-20I/SP fits industrial sensor interface boards because its integrated 8-bit ADC with 5 channels directly digitizes analog sensor outputs without external converter cost, while the 22 I/O pins handle digital sensors, status LEDs, and isolated outputs. At 20 MHz the PIC executes single-cycle instructions in 200 ns, sufficient for polled sensor scanning at kHz rates. The 3.5 KB OTP memory holds typical sensor-calibration and linearization routines. The industrial -40C to +85C temperature range tolerates factory-floor enclosures without derating, and brown-out reset prevents corrupted operation on noisy 24V-bus-derived 5V rails.
Recommended
HVAC Thermostat and Control Panel
In HVAC thermostat designs, the PIC16C72-20I/SP provides the central control brain with its 5-channel ADC reading temperature sensors (NTC thermistors, setpoint potentiometer), 22 I/O pins driving LCD segments, relay coils, and keypad matrix, and hardware USART linking to a wall-mounted network or BACnet module. The watchdog timer recovers the controller from firmware lockup if EMC events disrupt program flow. OTP memory secures the production firmware image from accidental reprogramming or tampering in field-deployed units.
Recommended
Appliance Control Board (Washer / Dishwasher)
Appliance control boards benefit from the PIC16C72-20I/SP's CCP/PWM module driving motor speed signals, the 5-channel ADC monitoring water level sensors and motor current via shunt, and 22 I/O pins switching solenoid valves, pump relays, and user-panel LEDs. The brown-out reset handles the harsh switched-mode power supply environment typical of white goods. The OTP memory locks the firmware revision for production, preventing field misprogramming, while the industrial temperature range survives the under-cabinet thermal environment of a dishwasher or the steam of a washing machine.
Recommended
Motor Control (Small BLDC / Stepper Driver)
The PIC16C72-20I/SP suits small motor control applications using its Capture/Compare/PWM module to generate timing signals for BLDC commutation or stepper pulse-and-direction sequencing. The 20 MHz clock provides 200 ns instruction timing for closed-loop PID calculations at 10 kHz update rates. Five ADC channels read back-EMF, current shunt, and supply voltage, while 22 I/O pins drive gate-driver ICs and fault inputs. The hardware USART connects to a host controller for command/monitoring, and the industrial temperature range tolerates the proximity to motor heat sources.
Recommended
Serial-Connected Sensor Node (RS-232/RS-485)
The PIC16C72-20I/SP functions as a serial sensor node leveraging its hardware USART module, which offloads baud-rate generation and framing from the CPU, freeing cycles for sensor acquisition. The 5-channel ADC handles multiple analog sensors, and the 22 I/O pins drive indicator LEDs and address-selection DIP switches. With 3.5 KB OTP and 128 bytes RAM, the firmware fits a polled protocol stack plus linearization tables. Industrial temperature and brown-out reset suit remote installations powered from 24V industrial buses.
Recommended
Simple User Interface Panel (Keypad + LCD)
In keypad-and-LCD user interface panels, the PIC16C72-20I/SP scans a matrix keypad, drives an HD44780-compatible character LCD in 4-bit mode, and handles background control tasks via its single hardware timer interrupt. The 22 I/O pins accommodate an 8-pin keypad port, 6 LCD data/control lines, and 8 control outputs to the host system. The CCP module generates a periodic interrupt for key debounce and LCD refresh, and the 20 MHz clock keeps the panel responsive without perceptible keypress lag. OTP memory locks the user-interface firmware against tampering.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C72-20I/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C72A-20I/SP | PIC16F72-I/SP | PIC16C72-20/SP | PIC16C72-20E/SP | PIC16C73-20I/SP |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SPDIP | 28-SPDIP - same | 28-SPDIP - same | 28-SPDIP - same | 28-SPDIP - same | 28-SPDIP - same |
| Program Memory Type | OTP (3.5 KB) | OTP (3.5 KB) | Flash (3.5 KB) | OTP (3.5 KB) | OTP (3.5 KB) | OTP (4 KB) |
| Maximum Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Temperature Range | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +125C (Extended) | -40C to +85C (Industrial) |
| Supply Voltage Range | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 2.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V |
| ADC Channels / Resolution | 5 / 8-bit | 5 / 8-bit | 5 / 8-bit | 5 / 8-bit | 5 / 8-bit | 8 / 8-bit |
| RAM Size | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 192 bytes |
| Reprogrammable (Flash) | No (OTP only) | No (OTP) | Yes (Flash, 100k cycles) | No (OTP) | No (OTP) | No (OTP) |
| Pin-to-Pin Compatible | N/A (reference part) | Yes (100%) | Yes (100%) | Yes (95%) | Yes (95%) | Yes (90%) |
Key Differentiators
- Integrated 5-channel 8-bit ADC at no extra cost (vs PIC16C71-20I/P)
- Hardware USART vs software bit-banging (vs PIC16C711-04I/P)
- Industrial temperature range vs commercial (vs PIC16C72-20/SP)
- Same 28-SPDIP pinout across multiple Microchip variants (vs PIC16C73-20I/SP)
Design Notes
The PIC16C72-20I/SP operates from 4.0 V to 5.5 V; operation below 4.0 V can trigger the brown-out reset or cause ADC inaccuracies. Use a bulk 10 uF electrolytic plus 100 nF ceramic decoupling as close to pins 18 (VDD) and 19 (VSS) as practical, with a second 100 nF on pin 28 (secondary VDD). For applications where the supply can dip during motor inrush or relay switching, add an MCP1700 LDO or Schottky diode with sufficient bulk capacitance to hold VDD above 4.0 V during transients.
Pin 1 (MCLR/VPP) requires an external 10 kohm pull-up to VDD for normal operation and must be decoupled with a 100 nF capacitor if in-circuit serial programming is intended. The OSC1/OSC2 pins (8/9) should be kept short and routed away from analog signals; for crystals, place load capacitors (typically 15-33 pF) within 5 mm of the pins and provide a ground guard ring. Analog inputs (RA0-RA5) benefit from a digital ground/analog ground split at the ADC reference pin to minimize digital switching noise coupling into ADC readings.
OTP memory cannot be erased - a single programming mistake or wrong firmware image bricks the device. Always verify the hex file checksum and device ID before initiating the programming cycle, and keep at least one verified blank device on hand for recovery. The configuration bits (fuses) must be set explicitly; an unprogrammed PIC16C72 defaults to RC oscillator mode with watchdog enabled, which can cause confusing symptoms if the oscillator configuration is not explicitly selected. Additionally, the I/O pin RA4 is open-drain and requires an external pull-up for high-output drive.
When using the USART at 20 MHz with high baud rates (above 57600), ensure that the RC6 (TX) and RC7 (RX) traces are short and routed away from switching signals. Place a 100 ohm series resistor on the TX line if driving long cables or connectors. For RS-485 half-duplex applications, use the TXEN/RXEN control bits with a 1-character turnaround delay before enabling the transmitter to avoid bus contention.
Compliance Information
RoHS compliance confirmed by Microchip product page and DigiKey listing for the /SP package suffix. AEC-Q100 not applicable - this is a general-purpose MCU, not automotive-qualified; automotive customers should select the PIC16C72A-20I/SP automotive equivalent. REACH compliance per Microchip declaration.
