PIC16LF721T-I/SS - 8-bit 16MHz 7KB Flash MCU 20-SSOP | Microchip
MPN: PIC16LF721T-I/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.66 | $16.60 |
| 100 | $1.48 | $148.00 |
| 500 | $1.32 | $660.00 |
| 1,000 | $1.18 | $1,180.00 |
| 2,500 | $1.05 | $2,625.00 |
PIC16LF721T-I/SS Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory, working RAM, and peripheral interfaces. The PIC16 (L)F720/721 series sits within Microchip's mid-range 8-bit portfolio, sharing the standard 14-bit instruction set and peripheral library with the larger PIC16F1xxx family. The 'LF' suffix indicates the wide 1.8V-3.6V operating range optimized for low-voltage, low-power systems rather than 5V industrial rails.
Key features include 7 KB flash with self-programmability, 256 bytes RAM, 18 I/O pins, a 10-bit ADC with up to 12 channels, two 8-bit timers plus one 16-bit timer, an enhanced USART, MSSP (SPI/I2C), and nanoWatt XLP modes that drop quiescent current to roughly 20 nA in sleep with watchdog disabled. The ICSP programming interface enables in-circuit flash updates, simplifying field firmware revisions.
Architecturally, the device uses Microchip's enhanced mid-range core, a 14-bit-wide instruction path and an 8-bit data path, with hardware multiplier-free integer math that is friendly to compiled C and hand-written assembly alike. The 16 MHz internal oscillator is accurate to ±1% over 0-85°C and ±2% over -40 to +125°C, removing the need for an external crystal in many designs.
Typical applications include battery-powered sensor nodes, smoke and CO detectors, remote controls, low-end LCD display modules, IoT edge nodes, and consumer white goods where cost and standby current dominate the BOM. In all of these, the wide voltage range and nanoWatt sleep modes extend battery life while the SSOP-20 footprint simplifies hand-solderable prototyping.
When designing with the PIC16LF721T-I/SS, note that the 'T' suffix denotes tape-and-reel packaging and the 'I' suffix indicates the industrial -40°C to +85°C temperature range. Use the MPLAB X IDE with XC8 compiler for firmware development, and configure unused I/O as outputs-low to minimize sleep current.
This page synthesizes distributor pricing, drop-in alternatives within the PIC16LF720/721 family, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16LF721T-I/SS — 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/SS (same form factor and footprint) — differing in Package, Operating Temperature, Timers, ADC, Internal Oscillator.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LF721-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF720-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF720T-I/SO
✅ Drop-In✓ In Stock
$0.86 / Unit
View Datasheet →PIC16LF720-I/SO
✅ Drop-In✓ In Stock
$0.85 / Unit
View Datasheet →PIC16LF720-E/SS
✅ Drop-In✓ In Stock
$1.18 / Unit
View Datasheet →PIC16LF720T-I/SS
✅ Drop-In✓ In Stock
$1.1 / Unit
View Datasheet →PIC16LF721T-I/SS Maximum Ratings & Electrical Characteristics
| Program Memory Type | Flash |
| Program Memory Size | 7 KB (4K x 14) |
| RAM Size | 256 bytes |
| CPU Core | PIC16 enhanced mid-range 8-bit |
| Maximum CPU Speed | 16 MHz |
| Operating Voltage Range | 1.8 V to 3.6 V |
| Supply Voltage (datasheet 'LF' range) | 2.3 V to 3.6 V per distributor listing |
| Number of I/O Pins | 18 |
| ADC | 10-bit, up to 12 channels |
| Timers | 2 x 8-bit, 1 x 16-bit |
| Communication Interfaces | EUSART, MSSP (SPI / I2C) |
| Internal Oscillator | 16 MHz (±1% over 0-85°C) |
| Low-Power Technology | nanoWatt XLP |
| Operating Temperature | -40°C to +85°C (industrial 'I' suffix) |
| Package | 20-pin SSOP (5.30 mm body width) |
| Mounting Type | Surface Mount |
| Programming Interface | ICSP (In-Circuit Serial Programming) |
| MSL Level | 1 |
| RoHS Status | Compliant |
PIC16LF721T-I/SS Pin Configuration
| Pin 1 | RA0/AN0 — Digital I/O / analog input channel 0 |
| Pin 2 | RA1/AN1 — Digital I/O / analog input channel 1 |
| Pin 3 | RA2/AN2 — Digital I/O / analog input channel 2 |
| Pin 4 | RA3/AN3/Vref+ — Digital I/O / analog input / ADC positive reference |
| Pin 5 | RA4/AN4 — Digital I/O / analog input channel 4 |
| Pin 6 | RA5/AN5 — Digital I/O / analog input channel 5 |
| Pin 7 | RA6/OSC2/CLKOUT — Digital I/O / oscillator output / clock out |
| Pin 8 | RA7/OSC1/CLKIN — Digital I/O / oscillator input / clock in |
| Pin 9 | VSS — Ground reference |
| Pin 10 | VDD — Positive supply voltage |
| Pin 11 | RB0/INT — Digital I/O / external interrupt |
| Pin 12 | RB1 — Digital I/O |
| Pin 13 | RB2 — Digital I/O |
| Pin 14 | RB3 — Digital I/O |
| Pin 15 | RB4 — Digital I/O |
| Pin 16 | RB5 — Digital I/O |
| Pin 17 | RB6/PGC — Digital I/O / ICSP clock |
| Pin 18 | RB7/PGD — Digital I/O / ICSP data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage |
Typical Applications
PIC16LF721T-I/SS is suitable for 7 applications: Battery-Powered Wireless Sensor Node, Smoke and CO Detector Controller, Infrared Remote Control, Low-End LCD Display Module, IoT Edge Sensor Hub, Consumer White Goods Control, Handheld Measurement Instrument.
Battery-Powered Wireless Sensor Node
The PIC16LF721T-I/SS suits coin-cell sensor nodes thanks to its 1.8V-3.6V supply range and nanoWatt XLP sleep modes that drop quiescent current to roughly 20 nA. Its 16 MIPS at 16 MHz is sufficient for periodic ADC readings over a 10-bit ADC and short RF packet bursts via EUSART or MSSP, while 7 KB flash holds a small MAC stack plus sensor drivers. Use two AA cells in series or a single CR2032 with a low Iq LDO.
Recommended
Smoke and CO Detector Controller
Smoke and CO detectors require an MCU that runs for years on a 9V battery or sealed lithium cell with stable ADC reads of the analog sensor front end. The PIC16LF721T-I/SS provides a 10-bit ADC with up to 12 channels, sleep current of about 20 nA, and an internal 16 MHz oscillator accurate to ±1% that removes the external crystal. Its EUSART supports a low-power wired interconnect to the sounder driver and the test LED.
Recommended
Infrared Remote Control
Consumer IR remotes need a low-cost, low-power MCU with timers for the carrier frequency and enough flash for button matrix scanning plus an IR protocol stack. The PIC16LF721T-I/SS delivers 16 MIPS for accurate 38 kHz / 56 kHz carrier generation, has 18 I/O for a 6x6 button matrix, and operates below 1 mA active at 3V. The 7 KB flash easily fits RC5/RC6 or NEC protocol plus wakeup logic.
Recommended
Low-End LCD Display Module
Character-LCD modules driven directly from an MCU need stable timing for the segment refresh and enough I/O for the 4-bit parallel interface plus backlight PWM. The PIC16LF721T-I/SS offers 18 I/O pins (more than enough for 4-bit LCD plus button inputs), a 16-bit timer for software-PWM backlight control, and 7 KB flash for bitmap fonts and menus. Wide voltage tolerance simplifies driving 3V or 5V LCD glass.
Recommended
IoT Edge Sensor Hub
Edge sensor hubs aggregate several analog or digital sensors and forward them over a low-power link like LoRa, BLE, or sub-GHz proprietary RF. The PIC16LF721T-I/SS acts as the always-on controller with the 10-bit ADC sampling multiple sensors while a companion radio module sleeps; the EUSART plus MSSP handle asynchronous serial links and I2C sensor reads. Sleep current of about 20 nA preserves battery life between bursts.
Recommended
Consumer White Goods Control
Small kitchen and home appliances need a robust 8-bit MCU for user-interface control, motor timing, and safety interlocks. The PIC16LF721T-I/SS provides nanoWatt XLP standby to meet energy-star idle budgets, a 10-bit ADC for temperature or humidity sensing, and an MSSP port for EEPROM or display drivers. The wide 1.8V-3.6V supply lets the same firmware build run on alkaline, NiMH, or single-cell Li-ion chemistries.
Recommended
Handheld Measurement Instrument
Portable DMMs, clamp meters, and insulation testers need an MCU that drives an LCD, reads an ADC, and supports button inputs while sipping current from a 9V or AA cells. The PIC16LF721T-I/SS provides a 10-bit ADC with up to 12 channels, an enhanced USART for the isolated serial port, and 18 I/O for the keypad. Industrial -40°C to +85°C temperature range covers outdoor measurement use cases.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LF721T-I/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LF721-I/SS | PIC16LF720-I/SS | PIC16LF720T-I/SS | PIC16LF720-E/SS |
|---|---|---|---|---|---|
| Package | 20-pin SSOP | 20-pin SSOP - same | 20-pin SSOP - same | 20-pin SSOP - same | 20-pin SSOP - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Flash | 7 KB | 7 KB | 3.5 KB | 3.5 KB | 3.5 KB |
| RAM | 256 bytes | 256 bytes | 128 bytes | 128 bytes | 128 bytes |
| Maximum CPU Speed | 16 MHz / 16 MIPS | 16 MHz / 16 MIPS | 16 MHz / 16 MIPS | 16 MHz / 16 MIPS | 16 MHz / 16 MIPS |
| Supply Voltage Range | 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 |
| Operating Temperature | -40C to +85C (industrial) | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +125C (extended) |
| Packaging | Tape & Reel | Tube | Tube | Tape & Reel | Tube |
| Pin-to-Pin Compatible | Yes (baseline) | Yes - 100% | Yes - 80% | Yes - 80% | Yes - 80% |
Key Differentiators
- Largest flash in PIC16LF720/721 SSOP-20 family (vs PIC16LF720T-I/SS)
- Same SSOP-20 footprint as the smaller-flash 720 (vs PIC16LF720-I/SS)
- Tape-and-reel packaging for high-volume assembly (vs PIC16LF721-I/SS)
- Industrial temperature range option within the family (vs PIC16LF720-E/SS)
Design Notes
The PIC16LF721T-I/SS nanoWatt XLP sleep mode draws about 20 nA with the watchdog timer disabled - this is critical for coin-cell budget designs. Per the Microchip datasheet, leaving the WDT enabled raises sleep current to roughly 1 µA; enable WDT only when periodic wakeup is required. Configure all unused I/O as digital outputs driving low (or high if no load) before executing the SLEEP instruction, since floating inputs can leak 1-10 µA through the CMOS input structure and dominate the total standby budget.
Place the 0.1 µF VDD decoupling capacitor within 3 mm of pins 10 and 20 (each VDD pin needs its own bypass). The PIC16LF721T-I/SS has two VDD pins (10 and 20) and two VSS pins (9 and 19); tie both VDD pins together on the top layer and both VSS pins together with a wide ground pour. If using the ADC, add a ferrite bead or 10 Ω resistor between AVdd and Vdd to isolate analog supply noise from the digital switching transients.
Keep the ICSP pins (RB6/PGC, RB7/PGD) on a dedicated 2x3 or 1x6 header so the device can be programmed in-circuit without removing it from the board. Per Microchip ICSP guidance, isolate the ICSP header from high-current traces to avoid programming glitches. The MCLR/VPP pin requires a 10-50 kΩ pull-down to VSS; do not drive MCLR with a strong pull-up since the ICSP programmer applies 12-13V on this pin during high-voltage programming.
When using the internal 16 MHz oscillator on the PIC16LF721T-I/SS, the accuracy is ±1% over 0-85°C and ±2% over -40 to +125°C. Per the datasheet, for UART communication above 57.6 kbaud or for tight timing protocols, switch to an external crystal on OSC1/OSC2 - the internal oscillator drift can otherwise exceed one bit time over a 16-byte payload. The EUSART auto-baud feature can compensate against a known host baud rate at startup.
Do not exceed 3.6V on any pin - the PIC16LF721T-I/SS is rated for 1.8-3.6V operation only; 5V signals on digital I/O will damage the device. If you must interface to a 5V rail, use a level translator like the TXS0108E or a simple resistive divider (1k/2k) for low-speed signals. The ADC reference voltage cannot exceed VDD, so for ratiometric measurements tied to VDD, use the internal bandgap reference rather than an external Vref+ tied to the supply rail.
Compliance Information
RoHS and lead-free compliance confirmed via the manufacturer datasheet and distributor listings (Hotenda, DigiKey). REACH compliance declared by Microchip. AEC-Q100 not applicable for the 'I' (industrial) grade; consider the 'E' (extended) variant for automotive. Halogen-free status not stated in the verified web data.
