PIC16LF721T-I/SO - 7KB Flash 8-bit MCU | Microchip 20-SOIC
MPN: PIC16LF721T-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.53 | $1.53 |
| 10 | $1.42 | $14.20 |
| 100 | $1.18 | $118.00 |
| 500 | $1.02 | $510.00 |
| 1,000 | $0.89 | $890.00 |
PIC16LF721T-I/SO Overview
A microcontroller (MCU) is an integrated circuit containing a CPU core, program memory (Flash/ROM), data memory (RAM), and peripherals such as timers, ADC, communication interfaces, and I/O pins on a single chip. PIC16 microcontrollers sit in the 8-bit RISC segment of the broader microcontroller taxonomy, which itself belongs to the larger power management and embedded control semiconductor family. They are commonly chosen for low-power, deterministic, cost-sensitive embedded designs.
Key features of the PIC16LF721 include 7 KB self-programmable Flash (4K x 14 words), 256 bytes of SRAM, 128 bytes of data EEPROM, 18 I/O pins, an enhanced 8-bit timer (Timer1/2/3) set, a 10-bit ADC with up to 14 channels, capture/compare/PWM modules, an I2C/SPI/USART (AUSART) interface, and nanoWatt XLP technology that drops the typical sleep current below 1 uA. The LF designator means the part is built for 1.8 V minimum operation, allowing direct battery connection in 2x AA / coin-cell designs.
The PIC16LF721T-I/SO uses a Harvard-architecture PIC16 RISC core with a 14-bit instruction word, single-cycle ALU operations, and a hardware multiplier. The LF process node and XLP design deliver active currents around 1 mA/MIPS at 3.3 V and standby currents of roughly 50-100 nA with the watchdog timer disabled, making the device well suited to always-on sensor nodes that spend most of their life in sleep.
Typical applications include battery-powered IoT sensor nodes, low-energy remote controls, wearable health patches, 2.4 GHz RF transmitter companion controllers, low-end motor control, and small consumer appliances. The industrial (-I) temperature grade of -40C to +85C supports outdoor and factory-floor deployment.
When designing, place a 100 nF decoupling capacitor on VDD as close to the pin as possible and bulk-decouple the MCLR line. Configure unused I/O as outputs driven low to minimize current draw in sleep, and use the LF variant only when sub-3.6 V battery operation is required; otherwise, the standard PIC16F721 (up to 5.5 V) provides more supply margin.
This page synthesizes distributor pricing, drop-in alternatives in the same 20-pin SOIC footprint, and practical low-power design notes beyond the datasheet to help engineers select and source the PIC16LF721T-I/SO quickly.
Drop-in alternatives for PIC16LF721T-I/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 PIC16LF721T-I/SO (same form factor and footprint) — differing in Package, Operating Temperature, Timers, ADC, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LF721-I/SO
✅ Drop-In✓ In Stock
$1.44 / Unit
View Datasheet →PIC16LF720T-I/SO
✅ Drop-In✓ In Stock
$0.86 / Unit
View Datasheet →PIC16LF720-I/SO
✅ Drop-In✓ In Stock
$0.85 / Unit
View Datasheet →PIC16LF721T-I/SS
✅ Drop-In✓ In Stock
$1.05 / Unit
View Datasheet →PIC16LF721T-I/MV
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF721T-I/SO Maximum Ratings & Electrical Characteristics
| Core | PIC16 (8-bit RISC, Harvard) |
| Instruction Word Width | 14-bit |
| Program Memory (Flash) | 7 KB (4K x 14) |
| Data Memory (SRAM) | 256 bytes |
| Data EEPROM | 128 bytes |
| Maximum CPU Speed | 16 MHz instruction rate |
| Internal Oscillator | Up to 32 MHz |
| Supply Voltage Range (LF) | 1.8 V to 3.6 V |
| I/O Pins | 18 |
| Package | 20-pin SOIC (SO), 7.50 mm width |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial) |
| Low-Power Feature | nanoWatt XLP |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC16LF721T-I/SO Pin Configuration
| Pin 1 | RA2/AN2 — Digital I/O RA2 / ADC analog input AN2 |
| Pin 2 | RA3/AN3/VREF1+ — Digital I/O RA3 / ADC AN3 / positive ADC reference |
| Pin 3 | RA4/AN4 — Digital I/O RA4 / ADC AN4 |
| Pin 4 | RA5/MCLR/VPP — Digital I/O RA5 / Master Clear (reset) / ICSP VPP |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RA6/OSC2/CLKOUT — Digital I/O RA6 / crystal oscillator output / CLKOUT |
| Pin 7 | RA7/OSC1/CLKIN — Digital I/O RA7 / crystal oscillator input / CLKIN |
| Pin 8 | RB4/AN10 — Digital I/O RB4 / ADC AN10 |
| Pin 9 | RB5/AN11 — Digital I/O RB5 / ADC AN11 |
| Pin 10 | RB6/ICSPCLK — Digital I/O RB6 / ICSP clock |
| Pin 11 | RB7/ICSPDAT — Digital I/O RB7 / ICSP data |
| Pin 12 | VDD — Positive supply (1.8 V to 3.6 V) |
| Pin 13 | RA0/AN0 — Digital I/O RA0 / ADC AN0 |
| Pin 14 | RA1/AN1 — Digital I/O RA1 / ADC AN1 |
| Pin 15 | RC0 — Digital I/O RC0 |
| Pin 16 | RC1 — Digital I/O RC1 |
| Pin 17 | RC2/CCP1 — Digital I/O RC2 / CCP1 PWM output |
| Pin 18 | RC3 — Digital I/O RC3 |
| Pin 19 | RC4/SDA/SDI — Digital I/O RC4 / I2C SDA / SPI SDI |
| Pin 20 | RC5/SCL/SCK — Digital I/O RC5 / I2C SCL / SPI SCK |
Typical Applications
PIC16LF721T-I/SO is suitable for 6 applications: Battery-Powered IoT Sensor Node, Low-Energy Remote Control, Wearable Health Patch, Small Consumer Appliance Controller, Automotive Interior LED Controller (Non-Safety), Industrial Sensor / 4-20 mA Loop Peripheral.
Battery-Powered IoT Sensor Node
The PIC16LF721T-I/SO is well suited as the always-on controller in coin-cell or 2x AA sensor nodes because its LF voltage range starts at 1.8 V and nanoWatt XLP sleep current stays below 1 uA. The PIC16 core wakes from sleep in a few instruction cycles, allowing a wake-measure-transmit cycle that consumes only tens of microamp-seconds. The 7 KB Flash holds small BLE/Zigbee stack shims plus sensor drivers, while 256 bytes SRAM is enough for short transmit buffers.
Recommended
Low-Energy Remote Control
In a battery-powered remote control, the PIC16LF721T-I/SO can stay in deep sleep for months, waking on a GPIO interrupt when a button is pressed and then driving an IR LED or 2.4 GHz transmitter. The 18 I/O pins easily accommodate 4x4 matrix keypads plus status LEDs, and the enhanced CCP PWM module can directly generate the 38 kHz carrier for IR transmission. The 1.8 V minimum supply lets a single CR2032 coin cell power the design across its full discharge curve.
Recommended
Wearable Health Patch
The PIC16LF721T-I/SO is an appropriate MCU for disposable or rechargeable wearable health patches because of its sub-microamp sleep current, 1.8 V operating range, and small 20-pin SOIC footprint. It can sample heart-rate or SpO2 sensors periodically using the 10-bit ADC, store calibration in 128 bytes of EEPROM, and wake a Bluetooth Low Energy radio only when a measurement is ready. The industrial -40C to +85C temperature range tolerates body-worn thermal environments.
Recommended
Small Consumer Appliance Controller
For small kitchen or personal-care appliances such as humidifiers, fans, or toothbrush chargers, the PIC16LF721T-I/SO provides enough Flash for state-machine control logic and EEPROM for user settings. The 18 I/O pins drive triac/relay outputs via optocouplers, sense water-level or capacitive touch inputs, and run the PWM fan or heater control loops. The wide -40C to +85C industrial grade handles steamy bathroom and outdoor-equipment environments.
Recommended
Automotive Interior LED Controller (Non-Safety)
In non-safety automotive interior applications such as ambient lighting or dashboard backlight dimming, the PIC16LF721T-I/SO drives CCP PWM channels for smooth color/brightness control while its AUSART links to a body-control CAN bridge. Note that the LF variant runs up to 3.6 V, so for 12 V automotive rails a regulator or LDO is still required. For AEC-Q100-qualified automotive needs, PIC16LF1903T-I/SO or similar PIC16LF1xxx-Q1 parts are recommended instead.
Recommended
Industrial Sensor / 4-20 mA Loop Peripheral
In 4-20 mA loop-powered sensor transmitters, the PIC16LF721T-I/SO's nanoWatt XLP sleep mode stretches loop-current budget during idle telemetry, while its 10-bit ADC directly digitizes sensor bridge outputs. The AUSART links to a HART modem or to a low-power wireless M-Bus radio for retrofit industrial deployments. The industrial -40C to +85C temperature grade supports outdoor and factory-floor use without derating.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LF721T-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LF721-I/SO | PIC16LF720T-I/SO | PIC16LF720-I/SO | PIC16LF721T-I/SS | PIC16LF721T-I/MV |
|---|---|---|---|---|---|---|
| Package | 20-SOIC (SO) | 20-SOIC (SO) - same | 20-SOIC (SO) - same | 20-SOIC (SO) - same | 20-SSOP (different footprint) | 20-UQFN (different footprint) |
| Brand | Microchip Technology | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same |
| Program Flash | 7 KB | 7 KB | 3.5 KB | 3.5 KB | 7 KB | 7 KB |
| Data SRAM | 256 bytes | 256 bytes | 128 bytes | 128 bytes | 256 bytes | 256 bytes |
| Data EEPROM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes |
| Supply Voltage | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V |
| I/O Pins | 18 | 18 | 18 | 18 | 18 | 18 |
| Packaging | Tape & Reel | Tube | Tape & Reel | Tube | Tape & Reel | Tape & Reel |
Key Differentiators
- Highest flash memory in the PIC16F720/721 20-SOIC family (vs PIC16LF720T-I/SO)
- Sub-3.6 V supply range for coin-cell designs (vs PIC16F721-I/SO (non-LF))
- Tube vs Tape & Reel packaging flexibility (vs PIC16LF721-I/SO)
Design Notes
Estimated: at 3.3 V VDD and 16 MHz Fosc the PIC16LF721T-I/SO active current is approximately 1 mA per MIPS, giving ~4 mA peak and ~1.5 mA average for typical loops. Use a 100 nF ceramic decoupling capacitor on VDD (pin 12) within 5 mm of the IC and add a 10 uF bulk capacitor on the battery rail. For coin-cell designs the LF variant is mandatory; a non-LF PIC16F721 will brown out below 2.0 V.
The 20-SOIC footprint (SO) has a 1.27 mm pin pitch. Always tie MCLR (pin 4) high through a 10 kohm resistor to VDD, or directly to VDD in non-debug builds, with a 100 nF cap to VSS to filter ESD. Place ICSP clock/data test points on RB6/RB7 (pins 10/11) so you can re-program the part on board. Keep the 32 kHz low-power crystal traces short if you use Timer1 sleep ticks.
Common pitfalls: (1) configuring unused I/O pins as analog inputs - they will float and waste current; set them as outputs driven low. (2) Running internal HFINTOSC above the LF spec's 3.6 V VDD limit - this damages the LF oscillator. (3) Forgetting to clear the WDT in long sleep cycles - the LF sleep tick must be < WDT timeout (~2 s typical) or the device will reset instead of sleeping. (4) Using PIC16F721 firmware on PIC16LF721 - the LF variant has reduced oscillator gain at <2 V and may need the LFINTOSC instead of HFINTOSC.
Compliance Information
RoHS and REACH compliant per Microchip product page; AEC-Q100 not qualified for automotive safety. Conflict-minerals compliant per Microchip supplier declaration.
