PIC16C72AT-04I/SO - 8-Bit 4MHz OTP MCU 3.5KB | Microchip
MPN: PIC16C72AT-04I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.96 | $2.96 |
| 10 | $2.71 | $27.10 |
| 100 | $2.45 | $245.00 |
| 500 | $2.21 | $1,105.00 |
| 1,000 | $1.99 | $1,990.00 |
PIC16C72AT-04I/SO Overview
An 8-bit OTP microcontroller (one-time-programmable microcontroller) is a single-chip computer that integrates a CPU, RAM, non-volatile program memory (here OTP EPROM), and peripherals on one die. OTP sits in the memory hierarchy below Flash and below mask-ROM: each cell can be programmed once by the user using a standard EPROM programmer, but cannot be electrically erased, making OTP parts cheaper than Flash for low-volume and mature products while still allowing code customization. Within the broader microcontroller taxonomy, the PIC16C72A belongs to Microchip's mid-range 8-bit PIC architecture (8-bit MCU -> mid-range MCU -> PIC16 family -> peripheral-rich PIC16C7x sub-family).
Key features include 35 single-word instructions, all executing in one instruction cycle except program branches which take two cycles, giving an instruction execution time of 200 ns at 20 MHz clock input (the part is rated for 4 MHz at this speed grade but the silicon supports up to 20 MHz on the -20 grade). Peripherals include two 8-bit timers and one 16-bit timer/counter with capture/compare/PWM (CCP) module, a synchronous serial port (SSP) supporting SPI and I²C, and a USART for asynchronous serial communication. The 22 I/O pins are bidirectional with individually programmable direction.
Typical applications include industrial control, appliance control, low-end sensor interfacing, and legacy embedded systems where the OTP memory cost advantage outweighs in-field reprogramming requirements. The 5-channel 8-bit ADC makes it suitable for simple analog monitoring tasks.
When designing with this part, verify the OTP memory constraint: code cannot be updated in the field. For prototypes or field-updatable designs, choose the Flash-based PIC16F72 equivalent. Programming requires a Microchip MPLAB-compatible device programmer supporting PIC16C OTP devices.
This page synthesizes distributor pricing, drop-in alternatives from the PIC16C7x family, and practical design notes not found in the standalone datasheet.
Drop-in alternatives for PIC16C72AT-04I/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 PIC16C72AT-04I/SO (same form factor and footprint) — differing in ADC, Package, Program Memory Size, Timers, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C72A-04I/SO
✅ Drop-In✓ In Stock
$3.5 / Unit
View Datasheet →PIC16C72AT-04/SO
✅ Drop-In✓ In Stock
$3.5 / Unit
View Datasheet →PIC16C72-04I/SO
✅ Drop-In✓ In Stock
$4.71 / Unit
View Datasheet →PIC16C72AT-04E/SO
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$6.08 / Unit
View Datasheet →PIC16C72AT-04I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16C mid-range 8-bit RISC |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 3.5 KB (2K x 14 words) |
| RAM Size | 128 bytes |
| Maximum Clock Input | 20 MHz (4 MHz grade for -04 suffix) |
| Instruction Cycle Time | 200 ns at 20 MHz |
| Instruction Set | 35 single-word instructions |
| I/O Pins | 22 |
| ADC | 5 channels, 8-bit resolution |
| Timers | 2 x 8-bit + 1 x 16-bit (with CCP) |
| Serial Interfaces | SSP (SPI/I²C), USART |
| Supply Voltage | 4.0 V to 5.5 V |
| Operating Temperature | -40 °C to +85 °C (industrial, "I" grade) |
| Package | 28-pin SOIC (SO), wide-body 7.50 mm |
| Mounting Type | Surface Mount |
| Delivery Form | Tape and Reel ("T" suffix) |
| RoHS Status | Compliant |
PIC16C72AT-04I/SO Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (Reset) input / programming voltage input |
| Pin 2 | RA0/AN0 — Port A bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / analog input 1 |
| Pin 4 | RA2/AN2 — Port A bit 2 / analog input 2 |
| Pin 5 | RA3/AN3/VREF — Port A bit 3 / analog input 3 / ADC voltage reference |
| Pin 6 | RA4/T0CKI — Port A bit 4 / Timer 0 clock input |
| Pin 7 | RA5/AN4/SS — Port A bit 5 / analog input 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 / Timer 1 oscillator output / Timer 1 clock input |
| Pin 11 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer 1 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 TX / USART clock |
| Pin 17 | RC7/RX/DT — Port C bit 7 / USART RX / USART data |
| Pin 18 | GND — Ground reference |
| Pin 19 | RD0 — Port D bit 0 |
| Pin 20 | RD1 — Port D bit 1 |
| Pin 21 | RD2 — Port D bit 2 |
| Pin 22 | RD3 — Port D bit 3 |
| Pin 23 | RD4 — Port D bit 4 |
| Pin 24 | RD5 — Port D bit 5 |
| Pin 25 | RD6 — Port D bit 6 |
| Pin 26 | RD7 — Port D bit 7 |
| Pin 27 | RE0/RD — Port E bit 0 / parallel slave port read |
| Pin 28 | VDD — Positive supply voltage (4.0 V to 5.5 V) |
Typical Applications
PIC16C72AT-04I/SO is suitable for 6 applications: Industrial Control Systems, Appliance Control Boards, Sensor Interface Modules, Automotive Body Electronics (Legacy), Low-End Consumer Electronics, Educational and Hobbyist Projects.
Industrial Control Systems
The PIC16C72AT-04I/SO is well-suited to industrial control panels where cost-sensitive, fixed-function logic drives relays, sensors, and actuators in factory-automation cells. The 5-channel 8-bit ADC directly monitors analog inputs such as temperature thermistors, supply voltages, and 4-20 mA loop sense resistors, while the 22 digital I/O pins handle switch debouncing, LED indicators, and discrete solenoid drives. The industrial -40 °C to +85 °C operating range covers unconditioned factory-floor cabinets. OTP memory locks the firmware against accidental in-field rewrite, which is a regulatory requirement in some safety-critical control loops. The 4 MHz clock and 35-instruction RISC core deliver deterministic 1 µs instruction execution suitable for PID-loop timing. Companion parts include the ULN2003A (relay/solenoid driver) and LM358 (analog front-end).
Recommended
Appliance Control Boards
White-goods appliances such as washing machines, dishwashers, and microwave ovens commonly deploy the PIC16C72AT-04I/SO on their main control board because the OTP-memory cost advantage lowers the BOM in high-volume SKUs. The 16-bit timer with CCP drives PWM-controlled motor speed for brushless-DC or universal-motor loads, while the 5-channel ADC reads water level, motor current, and temperature sensors. The USART enables diagnostics over a service-port interface, and the SSP supports SPI/I²C EEPROM for storing user setting preferences. The 28-SOIC wide-body package is compatible with wave-solder and reflow processes used in appliance manufacturing. Companion parts include the IRF540N (PWM motor switch) and 24LC256 (I²C EEPROM).
Recommended
Sensor Interface Modules
The PIC16C72AT-04I/SO serves as a low-cost front-end processor in sensor-interface modules that aggregate 4-20 mA, 0-10 V, or thermistor analog signals into a digital output. Its 5-channel 8-bit ADC provides sufficient resolution for non-precise monitoring, while the 22 I/O pins drive status LEDs, scan pushbuttons, and handshake with the upstream controller via SPI, I²C, or UART. The 4 MHz clock and 128-byte RAM are sufficient for averaging-filter and linearization routines on multiple channels. OTP memory locks the calibration coefficients at programming time, preventing end-user tampering with field-installed instrumentation. Companion parts include the XTR105 (4-20 mA current-loop transmitter) and MAX485 (RS-485 transceiver).
Recommended
Automotive Body Electronics (Legacy)
While not AEC-Q100 qualified, the PIC16C72AT-04I/SO and its -04I industrial grade have been deployed in non-safety automotive body-electronics modules such as HVAC blend-door actuators, seat controllers, and lighting modules where OEM cost targets dominate over qualification standards. The 5-channel ADC reads potentiometer position feedback and thermistor inputs, the 16-bit timer with CCP drives PWM-controlled motor speed, and the USART interfaces with body-control modules. The industrial -40 °C to +85 °C temperature grade covers under-dash ambient conditions. OTP memory locks the calibration table for production. Companion parts include the TLE4271 (5 V LDO) and BTS432E2 (high-side switch).
Recommended
Low-End Consumer Electronics
Battery-powered and line-powered consumer devices such as remote controls, toys, kitchen timers, and educational electronics use the PIC16C72AT-04I/SO as a low-cost controller because the OTP-memory silicon carries no Flash overhead. The 22 I/O pins drive LEDs, keypads, and piezo buzzers directly, while the 5-channel ADC reads battery voltage and simple analog inputs. The 4 MHz clock keeps active power consumption below 10 mW at 5 V, suitable for AC-adapter or 4 x AA battery operation. The 28-SOIC package is easy to hand-prototype and through-hole-rework-friendly. Companion parts include the 7805 (5 V regulator) and BC547 (NPN driver).
Recommended
Educational and Hobbyist Projects
The PIC16C72AT-04I/SO is popular in university embedded-systems courses and hobbyist projects because the 28-SOIC package is breadboard-friendly (with a SOIC-to-DIP adapter), the PIC16C mid-range instruction set is well-documented, and Microchip's MPLAB X IDE supports the PIC16C72A for assembly and C development. The 5-channel ADC and 22 I/O pins give students enough peripherals to build meaningful projects: digital thermometers, motor controllers, UART-monitored sensor nodes, and simple PWM servo drivers. OTP memory forces students to plan their code carefully before programming, a valuable pedagogical lesson. Companion parts include the PICkit 3 programmer and MCP9700 analog temperature sensor.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C72AT-04I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C72A-04I/SO | PIC16C72AT-04/SO | PIC16C72-04I/SO | PIC16C72AT-04E/SO | PIC16C72AT-04E/SS |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC wide-body | 28-SOIC wide-body (same) | 28-SOIC wide-body (same) | 28-SOIC wide-body (same) | 28-SOIC wide-body (same) | 28-SSOP (different footprint) |
| Program Memory Type | OTP EPROM | OTP EPROM (same) | OTP EPROM (same) | OTP EPROM (same) | OTP EPROM (same) | OTP EPROM (same) |
| Program Memory Size | 3.5 KB (2K x 14) | 3.5 KB (same) | 3.5 KB (same) | 3.5 KB (same) | 3.5 KB (same) | 3.5 KB (same) |
| Clock Grade | 4 MHz (-04) | 4 MHz (-04) (same) | 4 MHz (-04) (same) | 4 MHz (-04) (same) | 4 MHz (-04) (same) | 4 MHz (-04) (same) |
| Operating Temperature | -40 °C to +85 °C (industrial) | -40 °C to +85 °C (same) | 0 °C to +70 °C (commercial, lower) | -40 °C to +85 °C (same) | -40 °C to +125 °C (enhanced, wider) | -40 °C to +125 °C (enhanced) |
| Delivery Form | Tape and Reel | Tube (different packing) | Tape and Reel (same) | Tube | Tube | Tube |
| Silicon Die | PIC16C72A (Rev A) | PIC16C72A (same die) | PIC16C72A (same die) | PIC16C72 (older die) | PIC16C72A (same die) | PIC16C72A (same die) |
Key Differentiators
- Tape-and-Reel factory packaging versus Tube packing of sibling MPNs (vs PIC16C72A-04I/SO)
- Industrial -40 °C to +85 °C temperature range versus commercial grade (vs PIC16C72AT-04/SO)
- Wide-body 28-SOIC package for improved thermal and assembly margin (vs PIC16C72AT-04E/SS)
Design Notes
OTP program memory cannot be electrically erased. Verify firmware with PIC16F72 (Flash equivalent in same 28-SOIC footprint) during development, then commit to OTP for production. Blank-check OTP parts before programming - a partially programmed device will fail verification. Use Microchip MPLAB IPE with a PICkit 3 or ICD 3 programmer; older 16C OTP devices require VPP=13 V on the MCLR pin during programming per the Microchip programming specification.
VDD supply must be 4.0 V to 5.5 V for PIC16C72AT-04I/SO; operation below 4 V may cause ADC reference and brownout-reset misbehavior. Decouple VDD with a 100 nF ceramic capacitor placed within 5 mm of pin 28, plus a 10 µF bulk capacitor near the regulator. The analog supply AVdd (if used separately on this die) shares pin 28 and should be filtered with a ferrite bead and 10 µF + 100 nF network for ADC noise-sensitive designs.
Keep the 4 MHz crystal (or ceramic resonator) traces from OSC1 (pin 8) and OSC2 (pin 9) short and symmetrical, with a ground guard ring on both sides. Place the crystal within 10 mm of the IC. For ADC accuracy, route the analog inputs (RA0-RA5) away from the USART and PWM switching traces on RC2/RC6/RC7 to avoid coupled noise. The MCLR pin (pin 1) requires a 10 kΩ pull-up to VDD; for high-noise environments add a 100 nF capacitor from MCLR to ground to form an RC reset delay.
When using the USART at 4 MHz clock input, the achievable baud-rate accuracy depends on the selected SPBRG value and the internal 4 MHz oscillator tolerance. For baud rates above 57600, switch to the -10 or -20 clock grade for adequate timing margin. The ADC requires a minimum acquisition time of 19.2 µs at 5 V (per Microchip datasheet); insert a corresponding delay between channel selection and GO/DONE assertion to avoid sampling the previous channel.
The 28-SOIC wide-body package has theta_JA of approximately 85 °C/W (per Microchip package thermal data). At 5 V supply, 4 MHz clock, and all 22 I/O pins driving CMOS loads, typical active power is under 25 mW, so junction self-heating is below 2 °C - thermal management is generally not required. However, in sealed enclosures with no airflow, derate the maximum ambient by 5-10 °C to account for PCB-level heating.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified - do not use in automotive safety-critical applications. Lead-free matte-tin plating on SOIC-28 leads. Halogen-free per Microchip green-compound declaration.
