PIC16F721-I/P - 8-bit MCU, 7KB Flash, 20-Pin PDIP | Microchip
MPN: PIC16F721-I/P β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.18 | $2.18 |
| 10 | $1.96 | $19.60 |
| 100 | $1.65 | $165.00 |
| 500 | $1.38 | $690.00 |
| 1,000 | $1.12 | $1,120.00 |
PIC16F721-I/P Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, non-volatile program memory, and peripherals around an 8-bit data bus. The PIC16F721 belongs to the broader taxonomy of microcontroller -> embedded microcontroller -> flash MCU -> 8-bit RISC MCU -> semiconductor IC. Mid-range PIC16 devices use a 14-bit instruction word and 35 single-word instructions, allowing most instructions to execute in a single 200 ns instruction cycle at 20 MHz, which makes them easy to program yet powerful enough for consumer, industrial, and IoT edge applications.
Key differentiating features include a 12-channel 10-bit ADC, two 8-bit timers (TMR0/TMR2), one 16-bit timer (TMR1), a CCP module for capture/compare/PWM, hardware I2C/SPI/EUSART (AUSART) peripherals, 25 mA source/sink I/O drive, and on-board power-on reset (POR) plus brown-out reset (BOR). The nanoWatt XLP sleep current is in the order of single-digit microamps, enabling multi-year battery life in duty-cycled sensor nodes.
Architecturally the part uses a Harvard memory architecture with separate program and data buses plus an 8-level deep hardware stack, eliminating the need for software stack pointer management. The internal 16 MHz oscillator is factory-calibrated to within Β±1% across voltage and temperature, removing the external crystal in most designs and reducing BOM cost.
Typical applications include consumer white-goods control panels, low-cost remote controls, sensor conditioning front-ends, battery-powered HVAC transmitters, educational development kits, and replacement of legacy PIC16C/PIC16F parts in industrial machinery. The 18 I/O pins plus 12 ADC channels cover most small-signal acquisition tasks.
Designers should choose the -I (industrial) grade when the operating temperature range must cover -40C to +85C; the -E grade extends to +125C for under-hood or lighting applications. Decouple VDD with 100 nF plus 10 uF bulk capacitance placed within 5 mm of the IC, and reserve the ICSP/ICD pins (RB6/RB7) with 4.7 kohm pull-ups for in-circuit programming.
This page synthesizes distributor pricing, drop-in pin-compatible PIC16 alternatives, and practical design notes that go beyond the manufacturer datasheet to speed engineer selection and procurement.
Drop-in alternatives for PIC16F721-I/P 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 PIC16F721-I/P (same form factor and footprint) β differing in Package, Operating Temperature, Communication, Internal Oscillator, ADC.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F720-I/P
β Drop-Inβ In Stock
$1.02 / Unit
View Datasheet βPIC16F720-E/P
β Drop-Inβ In Stock
$1.24 / Unit
View Datasheet βPIC16F721-E/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16F716-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16F690-I/P
β Drop-Inβ In Stock
$1.89 / Unit
View Datasheet βPIC16F688-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16F721-I/P Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC16 mid-range RISC |
| Instruction Set | 35 single-word instructions, 14-bit opcode |
| Maximum CPU Speed | 16 MHz (16 MIPS) / 20 MHz |
| Program Memory (Flash) | 7 KB (4K x 14 words) |
| Data EEPROM | 128 bytes non-volatile |
| Data SRAM | 256 bytes |
| Hardware Stack | 8 levels |
| I/O Pins | 18 |
| ADC | 12-channel, 8-bit |
| Timers | 2x 8-bit (TMR0/TMR2), 1x 16-bit (TMR1) |
| Capture/Compare/PWM | 1x CCP module |
| Communication Peripherals | I2C, SPI, AUSART (EUSART) |
| Supply Voltage | 2.5 V to 5.5 V (PIC16F721-I/P variant) |
| Operating Temperature | -40C to +85C (industrial grade) |
| Package | 20-pin PDIP (through-hole) |
| Internal Oscillator | 16 MHz, factory calibrated |
| I/O Source/Sink Current | 25 mA per pin |
| Power-on Reset / Brown-out Reset | Yes (POR + BOR) |
| Watchdog Timer | Yes (WDT) |
| In-Circuit Serial Programming | Yes (ICSP via RB6/RB7) |
PIC16F721-I/P Pin Configuration
| Pin 1 | RA0/AN0/ICSPDAT β Bidirectional I/O / ADC channel 0 / ICSP data |
| Pin 2 | RA1/AN1 β Bidirectional I/O / ADC channel 1 |
| Pin 3 | RA2/AN2 β Bidirectional I/O / ADC channel 2 |
| Pin 4 | RA3/AN3/MCLR β Bidirectional I/O / ADC channel 3 / Master Clear Reset |
| Pin 5 | RA4/AN4 β Bidirectional I/O / ADC channel 4 |
| Pin 6 | RA5/AN5 β Bidirectional I/O / ADC channel 5 |
| Pin 7 | VSS β Ground reference |
| Pin 8 | RA7 β Bidirectional I/O (OSC1 alternate) |
| Pin 9 | RA6 β Bidirectional I/O (OSC2 alternate) |
| Pin 10 | RC0 β Bidirectional I/O |
| Pin 11 | RC1 β Bidirectional I/O |
| Pin 12 | RC2 β Bidirectional I/O |
| Pin 13 | RC3 β Bidirectional I/O |
| Pin 14 | RC4 β Bidirectional I/O |
| Pin 15 | RC5 β Bidirectional I/O |
| Pin 16 | RC6 β Bidirectional I/O |
| Pin 17 | RC7 β Bidirectional I/O |
| Pin 18 | RB7/ICSPCLK β Bidirectional I/O / ICSP clock |
| Pin 19 | VSS β Ground reference |
| Pin 20 | VDD β Positive supply voltage 1.8 V to 5.5 V |
Typical Applications
PIC16F721-I/P is suitable for 6 applications: Consumer Appliance Control Panels, Battery-Powered IoT Sensor Nodes, HVAC Remote Control Transmitters, Industrial Sensor Conditioning Front-Ends, Educational Development and Prototyping, Replacement for Legacy PIC16C/PIC16F Designs.
Consumer Appliance Control Panels
The PIC16F721-I/P is well suited for consumer appliance control panels including washing machines, microwave ovens, and induction cooktops where cost-sensitive 8-bit processing is sufficient. Its 7 KB flash accommodates multi-state user-interface logic, while the 12-channel 8-bit ADC reads multiple potentiometers, NTC temperature sensors, and current-sense inputs from a single MCU. The 25 mA source/sink I/O capability directly drives LED indicators and relay coils without external drivers, and the nanoWatt XLP sleep current below 50 nA typical lets the appliance meet standby power regulations under 0.5 W. Industrial -40C to +85C temperature operation covers indoor kitchen and laundry environments.
Recommended
Battery-Powered IoT Sensor Nodes
For battery-powered IoT sensor nodes, the PIC16F721-I/P delivers nanoWatt XLP sleep current down to 50 nA typical, enabling multi-year operation from a single CR2032 coin cell or 2x AA alkaline pack. The wide 1.8 V to 5.5 V supply range supports direct battery connection without an LDO, and the internal 16 MHz factory-calibrated oscillator eliminates the external crystal normally required for accurate timing. The 12-channel ADC reads multiple environmental sensors, while hardware I2C/SPI/AUSART peripherals connect to radios, EEPROM, or displays. Wake-up via Watchdog Timer or interrupt on pin change keeps average current in the single-digit microamp range for duty-cycled reporting.
Recommended
HVAC Remote Control Transmitters
The PIC16F721-I/P fits HVAC remote control transmitters where a small 20-pin PDIP MCU drives IR LEDs, scans keypad matrices, and handles bi-directional RF or IR communication. Its 16 MIPS performance executes modulation and button-debounce algorithms with margin, and the 256-byte SRAM comfortably holds protocol stacks for AC or heat-pump commands. The internal 16 MHz oscillator gives accurate timing for 38 kHz IR carriers, while the nanoWatt XLP sleep mode keeps a pair of AAA cells running for years of standby operation. Industrial temperature grade ensures reliable operation across indoor climate extremes from basement cold to attic heat.
Recommended
Industrial Sensor Conditioning Front-Ends
In industrial 4-20 mA loop transmitters, bridge sensor signal conditioners, and process-control front-ends, the PIC16F721-I/P combines a 12-bit ADC, 7 KB flash, and robust industrial temperature rating in a single 20-pin PDIP package. The CCP module generates PWM for H-bridge or valve actuators, while hardware I2C/SPI interfaces connect to digital sensors and DACs. The 256-byte SRAM supports calibration tables for linearization of thermocouples or strain gauges, and the nanoWatt XLP modes enable loop-powered designs drawing under 3.5 mA from the 4-20 mA current loop, leaving enough headroom for the sensor bridge.
Recommended
Educational Development and Prototyping
The PIC16F721-I/P is widely used in university microcontroller courses, hobbyist projects, and rapid prototyping kits because the 20-pin PDIP package is breadboard-friendly and the PIC16 mid-range instruction set has only 35 single-word instructions to teach. Microchip's MPLAB X IDE, XC8 compiler, and PICkit 4 programmer provide a free toolchain, while the PICkit Serial Analyzer and Curiosity Development Board offer low-cost development platforms. The 7 KB flash holds substantial C code for student projects, and ICSP via RB6/RB7 enables in-circuit programming without removing the chip from the breadboard.
Recommended
Replacement for Legacy PIC16C/PIC16F Designs
The PIC16F721-I/P is an excellent drop-in modernization for legacy PIC16C711, PIC16F84A, PIC16F627A, and PIC16F628A designs that need more flash and lower sleep current while preserving the 20-pin PDIP through-hole footprint. Industrial designs with existing through-hole assembly lines can retain wave-solder manufacturing while gaining nanoWatt XLP technology, ICSP, and modern peripherals. Firmware can be ported using MPLAB X's legacy project migration tools, and the PIC16 mid-range core ensures assembly-language code from older PICs often compiles unchanged, accelerating the upgrade path.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F721-I/P β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F720-I/P | PIC16F720-E/P | PIC16F721-E/P | PIC16F716-I/P | PIC16F690-I/P | PIC16F688-I/P |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | PDIP-20 | PDIP-20 - same | PDIP-20 - same | PDIP-20 - same | PDIP-20 - same | PDIP-20 - same | PDIP-20 - same |
| Program Memory (Flash) | 7 KB | 3.5 KB (50% less) | 3.5 KB (50% less) | 7 KB (same) | 14 KB (2x more) | 4 KB (43% less) | 7 KB (same) |
| Data SRAM | 256 B | 128 B (50% less) | 128 B (50% less) | 256 B (same) | 128 B (50% less) | 256 B (same) | 256 B (same) |
| ADC Channels | 12 channels, 8-bit | 12 channels, 8-bit | 12 channels, 8-bit | 12 channels, 8-bit | 8 channels, 8-bit (33% less) | 8 channels, 8-bit (33% less) | 8 channels, 8-bit (33% less) |
| Maximum Clock Speed | 16 MHz / 20 MHz | 16 MHz / 20 MHz | 16 MHz / 20 MHz | 16 MHz / 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +125C (Extended) | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) |
| nanoWatt XLP Sleep Current | Yes (<50 nA typical) | Yes (<50 nA typical) | Yes (<50 nA typical) | Yes (<50 nA typical) | No (older design) | Yes | No |
Key Differentiators
- Largest flash in the 20-pin PDIP PIC16 family with nanoWatt XLP (vs PIC16F720-I/P)
- 12 ADC channels versus 8 in the older PIC16F690-I/P (vs PIC16F690-I/P)
- Industrial temperature grade standard, extended grade available (vs PIC16F721-E/P)
Design Notes
Estimated: at VDD = 5 V and active mode at 16 MHz, the PIC16F721-I/P draws approximately 1.4 mA typical core current plus I/O loading. For battery-powered designs, switch to 31 kHz LFINTOSC during sleep to drop supply current below 50 nA typical per the nanoWatt XLP section of the Microchip datasheet. Always decouple VDD pin 20 with a 100 nF X7R ceramic placed within 5 mm of the package and add a 10 uF bulk tantalum or aluminum-polymer capacitor at the board power entry. The MCLR pin 4 should have a 10 kohm pull-up to VDD for normal operation.
Reserve ICSP pins RB7 (pin 18) and RA0 (pin 1) for the PICkit programmer by adding 4.7 kohm pull-up resistors on RB7/ICSPCLK and isolating the MCLR line with a resistor-diode network so a production programmer can attach without depopulating parts. Keep the 20-pin PDIP on a 0.1 inch (2.54 mm) pitch header row so it can be socketed or replaced during prototyping. Route the analog inputs (RA0-RA5) away from switching nodes such as relay coils or PWM outputs, and surround the analog ground with a guard trace tied to VSS to reduce ADC noise pickup on the 8-bit conversion.
Do not exceed the absolute maximum VDD of 6.5 V or the latch-up current on any I/O pin of 20 mA. The PIC16F721-I/P's ADC reference is VDD; if the supply is noisy the conversion will be noisy - use a clean 3.3 V or 5 V rail, not a switching node. When migrating from PIC16F84A code, ensure CONFIG bits are re-set for the PIC16F721's oscillator and watchdog timer since the default configuration differs. Finally, when entering sleep mode, clear the ADC enable bit ADON to avoid the ADC keeping the chip awake and drawing extra current.
Compliance Information
RoHS and REACH compliant per Microchip product declaration; lead-free PDIP package. Not AEC-Q100 qualified; for automotive applications consider PIC16F1779 or PIC18F family with AEC-Q100 Grade 0 or Grade 1 certification. Halogen-free per JESD709.
