PIC16C72-04/SO - 4MHz 8-Bit OTP MCU 28-SOIC | Microchip
MPN: PIC16C72-04/SO β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.1 | $6.10 |
| 10 | $5.49 | $54.90 |
| 100 | $4.86 | $486.00 |
| 500 | $4.15 | $2,075.00 |
| 1,000 | $3.45 | $3,450.00 |
PIC16C72-04/SO Overview
An 8-bit microcontroller (MCU) is a small computer-on-a-chip that combines a CPU, RAM, ROM/Flash/OTP program memory, and peripherals on a single die. Microcontrollers sit within the embedded systems hierarchy: MCU -> embedded processor -> semiconductor -> integrated circuit. The PIC16C7X family targets cost-sensitive embedded control applications, while the OTP memory variant (PIC16Cxx) is intended for low-volume production and prototype builds where in-circuit reprogrammability is not required.
Key features of the PIC16C72-04/SO include 35 single-word instructions (most executed in one instruction cycle, except program branches at two cycles), 200 ns instruction cycle at 20 MHz (4 MHz in this -04 speed grade), parallel slave programming via a boot loader, and an operating voltage range of 4.0 V to 5.5 V. The mid-range PIC16CXX core provides deterministic instruction timing and bit-manipulation primitives optimized for control loops.
Architecturally, the PIC16C72-04/SO uses a Harvard-style architecture with separate program and data buses, enabling simultaneous instruction fetch and data access. The integrated 8-bit ADC and PWM module support closed-loop motor and analog-sensor interfaces, while the BOR and watchdog timer (WDT) enhance field reliability against brown-out and software-stuck conditions.
Typical applications include consumer appliance control, HVAC thermostat logic, simple motor-control boards, low-end sensor signal conditioning with ADC, and industrial automation front-ends. Engineers should note that Microchip flags the PIC16C72 family as having a newer revision available: consider the PIC16C72A (compatible drop-in) or PIC16F72 (flash-based reprogrammable successor) for new designs.
When designing with this part, ensure Vdd stays within 4.0 V to 5.5 V and respect the wide-body SOIC-28 PCB land pattern (300 mil body width). OTP parts cannot be erased - design firmware to be fully validated before final programming.
This page synthesizes real-time distributor pricing, drop-in alternatives (PIC16C72A, PIC16F72), and practical OTP-MCU design notes not found on the bare manufacturer datasheet, helping engineers select, source, and lay out the part with confidence.
Drop-in alternatives for PIC16C72-04/SO 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 PIC16C72-04/SO (same form factor and footprint) β differing in Package, Timers, RoHS Status, ADC, Core Architecture.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C72A-04/SO
β Drop-Inβ In Stock
$5.22 / Unit
View Datasheet βPIC16C72-04I/SO
β Drop-Inβ In Stock
$4.71 / Unit
View Datasheet βPIC16C72A-04I/SO
β Drop-Inβ In Stock
$3.5 / Unit
View Datasheet βPIC16C72A-20/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16F72-I/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16F72T-I/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16C72-04/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16CXX mid-range 8-bit RISC |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle Time | 200 ns at 20 MHz (4 MHz speed grade) |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 3.5 KB (2K x 14) |
| Data RAM | 128 bytes |
| Data EEPROM | Not present (OTP family) |
| I/O Pins | 22 |
| ADC | 8-bit, multichannel |
| PWM Channels | 1 |
| Timers | Timer0 8-bit with 8-bit prescaler (plus additional timers per datasheet) |
| Brown-out Reset (BOR) | Yes |
| Watchdog Timer (WDT) | Yes |
| Supply Voltage (Vdd) | 4.0 V to 5.5 V |
| Operating Temperature Range | Commercial (0C to +70C) for -04/SO suffix |
| Package | 28-pin SOIC (SO, 300-mil wide body) |
| Mounting Type | Surface Mount |
| RoHS Status | unknown |
| Lead-Free | unknown |
| Process Technology | CMOS, fully-static |
PIC16C72-04/SO Pin Configuration
| Pin 1 | RA2/AN2 β Port A bit 2 / Analog input 2 |
| Pin 2 | RA3/AN3 β Port A bit 3 / Analog input 3 |
| Pin 3 | RA4/T0CKI β Port A bit 4 / Timer0 clock input |
| Pin 4 | RA5/AN4 β Port A bit 5 / Analog input 4 |
| Pin 5 | Vss β Ground reference |
| Pin 6 | OSC1/CLKIN β Crystal oscillator input / external clock |
| Pin 7 | OSC2/CLKOUT β Crystal oscillator output / clock output |
| Pin 8 | RB0/INT β Port B bit 0 / external interrupt |
| Pin 9 | RB1 β Port B bit 1 |
| Pin 10 | RB2 β Port B bit 2 |
| Pin 11 | RB3 β Port B bit 3 |
| Pin 12 | RB4 β Port B bit 4 |
| Pin 13 | RB5 β Port B bit 5 |
| Pin 14 | RB6 β Port B bit 6 |
| Pin 15 | RB7 β Port B bit 7 |
| Pin 16 | Vdd β Positive supply (4.0 V to 5.5 V) |
| Pin 17 | RC0 β Port C bit 0 |
| Pin 18 | RC1 β Port C bit 1 |
| Pin 19 | RC2/CCP1 β Port C bit 2 / PWM output |
| Pin 20 | RC3 β Port C bit 3 |
| Pin 21 | RC4 β Port C bit 4 |
| Pin 22 | RC5 β Port C bit 5 |
| Pin 23 | RC6 β Port C bit 6 |
| Pin 24 | RC7 β Port C bit 7 |
| Pin 25 | Vss β Ground reference (second Vss pin) |
| Pin 26 | RA0/AN0 β Port A bit 0 / Analog input 0 |
| Pin 27 | RA1/AN1 β Port A bit 1 / Analog input 1 |
| Pin 28 | Vdd β Positive supply (second Vdd pin) |
Typical Applications
PIC16C72-04/SO is suitable for 6 applications: Consumer Appliance Control, HVAC Thermostat Logic, Simple Motor-Control Boards, Low-End Sensor Signal Conditioning, Industrial Automation Front-Ends, Educational and Hobby Electronics.
Consumer Appliance Control
The PIC16C72-04/SO fits consumer appliance control boards (washing machines, dishwashers, microwave ovens, rice cookers) where its 4 MHz PIC16CXX core, 3.5 KB OTP, 22 I/O pins, and integrated 8-bit ADC provide enough compute for sensor reading, relay driving, and user-interface button scanning. The brown-out reset (BOR) and watchdog timer (WDT) enhance field reliability against mains-borne brown-outs and software lock-ups. With 4.0 V to 5.5 V supply and a commercial temperature grade, it operates directly from a 5 V rectified mains rail. Compared to flash-MCU alternatives like the PIC16F72, the OTP variant suits mature, fully-validated production firmware where per-unit programming cost dominates.
Recommended
HVAC Thermostat Logic
HVAC thermostat and building-control front-ends use the PIC16C72-04/SO to read NTC thermistor temperatures via the integrated 8-bit ADC, drive TRIACs through PWM and GPIO, and scan a matrix of front-panel buttons. The 128 bytes of RAM is sufficient for setpoint storage, hysteresis state machines, and small LCD driver buffers without external memory. Its 4 MHz clock and 200 ns instruction cycle deliver responsive control loop latency. The 28-SOIC package is easy to hand-prototype or low-cost reflow, and the brown-out reset prevents erratic operation during compressor inrush. For HVAC systems requiring field firmware updates, the PIC16F72-I/SO offers identical peripherals with flash reprogrammability.
Recommended
Simple Motor-Control Boards
Low-end DC motor and stepper motor control boards leverage the PIC16C72-04/SO's PWM output for speed regulation, 22 I/O pins for H-bridge drive signals, and 8-bit ADC for back-EMF or tachogenerator feedback. The mid-range PIC16CXX core handles simple PID loops at 4 MHz within the 1 microsecond instruction cycle budget. The integrated brown-out reset and watchdog timer are critical for motor applications where stall-induced supply dips can corrupt the firmware. The OTP memory is acceptable for production motor controllers with finalized control algorithms. Engineers should budget 1-2 ms PWM period (typical 1-2 kHz) and ensure H-bridge dead-time is handled in firmware.
Recommended
Low-End Sensor Signal Conditioning
The PIC16C72-04/SO is well-suited as a sensor hub front-end for low-channel-count industrial sensor modules where its 8-bit ADC, 22 I/O, and 128-byte RAM allow digitization of analog sensors (temperature, pressure, humidity) and digital sensor I/O expansion via I/O pins. The 4 MHz clock provides sufficient throughput for 100 Hz sampling rates across multiple channels. The brown-out reset and watchdog timer prevent field failures in industrial environments. The 28-SOIC package simplifies PCB layout on standard 2-layer boards. Compared to higher-end Cortex-M0+ alternatives, the PIC16C72-04/SO offers significant cost savings for high-volume sensor modules where 8-bit ADC resolution is acceptable.
Recommended
Industrial Automation Front-Ends
Programmable logic controller (PLC) input modules and industrial automation front-ends use the PIC16C72-04/SO to scan 16-22 discrete inputs (push-buttons, limit switches, proximity sensors), drive indicator LEDs, and communicate with a master controller via UART or I/O expander. The 3.5 KB OTP program memory holds ladder-logic-equivalent state machines. The brown-out reset and watchdog timer are essential for industrial immunity to EMI-induced supply dips. The commercial temperature grade is acceptable for indoor cabinets; for outdoor or factory-floor deployments, the industrial-grade PIC16C72-04I/SO variant (-40C to +85C) should be specified. Engineers should add external ESD protection on I/O pins per IEC 61000-4-2 requirements.
Recommended
Educational and Hobby Electronics
Universities, technical colleges, and hobbyists use the PIC16C72-04/SO as a teaching platform for embedded programming courses, thanks to its mid-range PIC16CXX architecture which balances simplicity (35 instructions) with realistic peripherals (ADC, PWM, timers, BOR, WDT). The 4 MHz clock and 200 ns instruction cycle allow real-time demonstrations of control loops without high-speed signal integrity concerns. The 28-SOIC wide-body package is easy to hand-solder on breakout boards. However, because OTP memory cannot be erased, educational programs increasingly prefer the flash-based PIC16F72-I/SO which offers identical peripherals with in-circuit reprogrammability via ICSP.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C72-04/SO β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C72A-04/SO | PIC16C72-04I/SO | PIC16C72A-04I/SO | PIC16C72A-20/SO | PIC16F72-I/SO |
|---|---|---|---|---|---|---|
| Package | 28-SOIC (SO, 300-mil) | 28-SOIC (SO, 300-mil) - same | 28-SOIC (SO, 300-mil) - same | 28-SOIC (SO, 300-mil) - same | 28-SOIC (SO, 300-mil) - same | 28-SOIC (SO, 300-mil) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | OTP (3.5 KB) | OTP (3.5 KB) | OTP (3.5 KB) | OTP (3.5 KB) | OTP (3.5 KB) | Flash (reprogrammable) |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz | 20 MHz |
| Program Memory Size | 3.5 KB (2K x 14) | 3.5 KB (2K x 14) | 3.5 KB (2K x 14) | 3.5 KB (2K x 14) | 3.5 KB (2K x 14) | 3.5 KB (2K x 14) flash |
| Data RAM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes |
| Operating Temperature | 0C to +70C (Commercial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) |
| Supply Voltage | 4.0 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 | 4.0 V to 5.5 V | 2.0 V to 5.5 V (wider) |
| Reprogrammable | No (OTP) | No (OTP) | No (OTP) | No (OTP) | No (OTP) | Yes (Flash, ICSP) |
Key Differentiators
- Mature, actively-stocked OTP MCU with established Microchip tooling (vs PIC16F72-I/SO (flash-based successor))
- Same 28-SOIC footprint as the entire PIC16C72/72A/16F72 family (vs PIC16F72-I/SO)
- Errata-fixed successor available as drop-in (PIC16C72A-04/SO) (vs PIC16C72-04/SO (original))
Design Notes
The PIC16C72-04/SO requires a stable 4.0 V to 5.5 V supply on Vdd. Place a 100 nF decoupling capacitor as close as possible to each Vdd pin (pin 16 and pin 28) and a 10 uF bulk capacitor near the package to suppress switching transients. The integrated brown-out reset (BOR) will trigger a device reset if Vdd sags below the BOR threshold (~4.0 V typical), preventing unpredictable execution during mains brown-outs. For applications with high inrush (relay coils, motor loads), add a series inductor or ferrite bead on the supply rail feeding the MCU to isolate the digital supply from analog noise.
The PIC16C72-04/SO uses OTP (one-time-programmable) memory which cannot be erased after programming. Engineers must fully validate firmware on a flash-equivalent prototype (PIC16F72-I/SO recommended) before committing to OTP programming. Also note that the -04 speed grade is limited to 4 MHz maximum - do not attempt to drive the OSC1 pin with a 20 MHz crystal as the silicon will not execute reliably above 4 MHz. For higher performance, migrate to the -20 speed grade or PIC16F72-I/SO. Finally, respect the 28-SOIC-300 land pattern - it is wider (300 mil body) than narrow-body SOIC packages and is not pin-compatible with 28-SSOP footprints.
The PIC16C72-04/SO in the 28-SOIC package has a junction-to-ambient thermal resistance (theta_JA) of approximately 60-80 C/W depending on PCB copper area. At typical 5 V / 4 MHz operation the device dissipates well under 100 mW, so thermal management is not a concern for normal commercial-grade applications (0C to +70C). For industrial-grade deployments using the PIC16C72-04I/SO variant (-40C to +85C), provide at least 100 mm^2 of ground-plane copper connected to the Vss pins (pin 5 and pin 25) to keep junction temperature below 125C at 85C ambient.
For the 28-SOIC wide-body footprint, route traces at least 0.2 mm (8 mil) wide with 0.2 mm spacing to maintain reflow yield. Place the decoupling capacitors on the same PCB side as the MCU, with the shortest possible loop between each Vdd pin and its decoupling cap. The OSC1/OSC2 crystal or resonator should be within 5 mm of pins 6-7, with a ground guard ring around the oscillator traces to reduce EMI pickup. Route the ADC analog inputs (AN0-AN4 on port A) away from digital switching signals; consider a ground plane separation between analog and digital sections if the board supports it.
Compliance Information
Compliance information not specified in the verified web data. The PIC16C72-04/SO is a mature Microchip legacy product; RoHS/lead-free status depends on the specific date/lot code. Engineers should request the latest RoHS/REACH declaration from Microchip or check the distributor product page for the -04/SO variant before specifying in RoHS-required designs.
