PIC16F721-E/SS - 8-bit MCU 7KB Flash 16MHz SSOP-20 | Microchip
MPN: PIC16F721-E/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.36 | $1.36 |
| 10 | $1.22 | $12.20 |
| 100 | $1.08 | $108.00 |
| 500 | $0.96 | $480.00 |
| 1,000 | $0.85 | $850.00 |
PIC16F721-E/SS Overview
A PIC microcontroller (Programmable Interface Controller) is a Harvard-architecture RISC MCU widely used in embedded control for its deterministic instruction set, low power, and rich peripheral integration. Within the Microchip taxonomy, the PIC16F721 sits inside the mid-range PIC16F family (sub-family PIC16F720/721), which belongs to the broader 8-bit MCU category, itself a branch of microcontrollers and embedded processors in the semiconductor hierarchy. The 'F' suffix indicates Flash program memory, and the '721' is the higher-pinout / higher-memory sibling of the PIC16F720.
Key features of the PIC16F721-E/SS include an internal 16 MHz oscillator (eliminating an external crystal in most designs), 12 channels of 8-bit ADC, an AUSART (asynchronous/synchronous USART), I2C and SPI master/slave ports, one Capture/Compare/PWM (CCP) module, two 8-bit timers (TMR0/TMR2) plus one 16-bit timer (TMR1), a watchdog timer with on-chip oscillator, brown-out reset, power-on reset, in-circuit serial programming, and nanoWatt XLP extreme-low-power technology for sleep currents down to the nanoampere range. I/O pins can source or sink 25 mA, sufficient to drive LEDs and small relays directly.
The 'E' in the suffix indicates the extended (-40 °C to +125 °C) operating temperature grade, and 'SS' denotes the SSOP-20 package. The 'I' grade variant (PIC16F721-I/SS) covers the industrial -40 °C to +85 °C range. Voltage operation spans 1.8 V to 5.5 V, supported by the on-chip voltage regulator and the nanoWatt XLP architecture. The RISC pipeline executes most instructions in a single 200 ns cycle at 20 MHz (16 MHz at the maximum internal oscillator setting), simplifying real-time scheduling.
Typical applications include low-power remote sensor nodes, battery-backed thermostats and metering, white-goods and small-appliance control boards, LED lighting controllers, automotive body modules (interior lighting, mirror control, seat switches) when paired with the automotive-grade PIC16F721T variant, USB-to-UART bridges paired with an external transceiver, and consumer electronics user-interface boards with keypad scanning and PWM-driven backlights. The combination of 18 usable I/O, internal oscillator, ADC, and nanoWatt XLP makes it a strong fit when the design must run for years on a coin cell or two AA cells.
When designing with this part, place a 100 nF decoupling capacitor as close as possible to VDD/VSS and a bulk capacitor on the AVDD/AVSS analog pair if the ADC is in use. Hold MCLR high through the recommended 10 kΩ/100 nF rise-time network for reliable in-circuit serial programming and reset behavior. Because the internal oscillator is factory calibrated but not user-trimmed at 1 % across the full voltage range, applications requiring tight UART timing should select the 16 MHz HS mode with an external crystal.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16F721-E/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 PIC16F721-E/SS (same form factor and footprint) — differing in ADC, Package, Timers, Core Architecture, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F721-I/SS
✅ Drop-In✓ In Stock
$1.2 / Unit
View Datasheet →PIC16F721T-I/SS
✅ Drop-In✓ In Stock
$1.18 / Unit
View Datasheet →PIC16F720-I/SS
✅ Drop-In✓ In Stock
$0.82 / Unit
View Datasheet →PIC16F720T-I/SS
✅ Drop-In✓ In Stock
$1.02 / Unit
View Datasheet →PIC16F690-I/SS
✅ Drop-In✓ In Stock
$1.41 / Unit
View Datasheet →PIC16F721-E/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 enhanced mid-range 8-bit RISC |
| Instruction Set Size | 35 instructions |
| Program Memory (Flash) | 7 KB (4K x 14 words) |
| Data SRAM | 256 B |
| Non-volatile Data EEPROM | 128 B |
| Maximum CPU Speed | 16 MHz (200 ns instruction cycle) |
| Stack Levels | 8 |
| Operating Voltage | 1.8 V to 5.5 V (2.5 V / 3.3 V / 5 V rails supported) |
| Operating Temperature | -40 °C to +125 °C (extended 'E' grade) |
| I/O Pins | 18 |
| I/O Source/Sink Current | 25 mA per pin |
| ADC | 12-channel, 8-bit resolution |
| Timers | Two 8-bit (TMR0/TMR2), one 16-bit (TMR1) |
| Communication Peripherals | AUSART, I2C, SPI |
| PWM Modules | 1 x CCP (Capture/Compare/PWM) |
| Watchdog Timer | Yes, with dedicated on-chip oscillator |
| Reset Features | POR, BOR, MCLR, WDT |
| Low-Power Technology | nanoWatt XLP |
| Package | SSOP-20 (5.30 mm body, 0.65 mm pitch) |
| Programming Interface | In-Circuit Serial Programming (ICSP) |
| Mounting Type | Surface Mount |
PIC16F721-E/SS Pin Configuration
| Pin 1 | MCLR/VPP/RA3 — Master Clear (reset) input / programming voltage / PORTA bit 3 |
| Pin 2 | RA0 — PORTA bit 0 (analog AN0) |
| Pin 3 | RA1 — PORTA bit 1 (analog AN1) |
| Pin 4 | RA2 — PORTA bit 2 (analog AN2) |
| Pin 5 | RC0 — PORTC bit 0 (analog AN4) |
| Pin 6 | RC1 — PORTC bit 1 (analog AN5) |
| Pin 7 | RC2 — PORTC bit 2 (analog AN6, CCP1 output) |
| Pin 8 | RC3 — PORTC bit 3 (analog AN7) |
| Pin 9 | RC4 — PORTC bit 4 (analog AN8) |
| Pin 10 | RC5 — PORTC bit 5 (analog AN9) |
| Pin 11 | VSS — Ground reference |
| Pin 12 | VDD — Positive supply voltage (1.8 V to 5.5 V) |
| Pin 13 | RC6 — PORTC bit 6 (AUSART TX) |
| Pin 14 | RC7 — PORTC bit 7 (AUSART RX) |
| Pin 15 | RB4 — PORTB bit 4 (interrupt-on-change) |
| Pin 16 | RB5 — PORTB bit 5 (interrupt-on-change) |
| Pin 17 | RB6 — PORTB bit 6 (ICSP clock / interrupt-on-change) |
| Pin 18 | RB7 — PORTB bit 7 (ICSP data / interrupt-on-change) |
| Pin 19 | VSS — Ground reference |
| Pin 20 | RA5 — PORTA bit 5 (analog AN11) |
Typical Applications
PIC16F721-E/SS is suitable for 6 applications: Battery-Backed Sensor Node, White-Goods Control Board, LED Lighting Controller, Automotive Body Module, USB-to-UART Bridge Dongle, Consumer User-Interface Board.
Battery-Backed Sensor Node
The PIC16F721-E/SS is well suited to battery-backed sensor nodes because its nanoWatt XLP architecture delivers tens of nanoamperes in Sleep while the internal 16 MHz oscillator wakes the part in microseconds for periodic ADC reads. The 12-channel 8-bit ADC directly digitizes thermistor, photocell, and battery-divider signals without external signal conditioning, and the 128 B of EEPROM lets the node store calibration constants and last-known-state data across power cycles.
Recommended
White-Goods Control Board
The PIC16F721-E/SS fits white-goods control boards (washing machines, dishwashers, microwave ovens) thanks to its 18 robust I/O pins rated at 25 mA source/sink, which can drive triac interfaces, LED indicators, and keypads directly. The AUSART and I2C peripherals support communication with the user-interface board and an external EEPROM or RTC, while the CCP module generates PWM for variable-speed motor control. The extended -40 °C to +125 °C temperature grade covers appliance thermal environments.
Recommended
LED Lighting Controller
In LED lighting controllers the PIC16F721-E/SS uses its CCP module to generate PWM dimming signals and its AUSART to receive DMX-512 or proprietary lighting-protocol commands from an upstream controller. The internal 16 MHz oscillator eliminates the crystal BOM and reduces board area, while nanoWatt XLP keeps standby power below 0.1 W to meet stringent energy regulations. The 7 KB Flash comfortably holds color-mixing tables and dimming curves.
Recommended
Automotive Body Module
The PIC16F721-E/SS supports automotive body modules such as interior lighting, mirror control, and seat-position switches where its extended -40 °C to +125 °C grade and 18 I/O pins meet the requirements. The 7 KB Flash holds CAN-friendly message-filter tables or LIN slave firmware, and the AUSART implements a LIN slave using the on-chip timer as the baud-rate reference. The internal oscillator survives engine-bay vibration better than a discrete crystal.
Recommended
USB-to-UART Bridge Dongle
The PIC16F721-E/SS serves as a low-cost USB-to-UART bridge when paired with an external USB transceiver, since its AUSART provides full hardware flow control at up to 115200 baud and the 7 KB Flash accommodates USB-CDC class drivers or vendor-specific firmware. The internal 16 MHz oscillator provides the ±2 % accuracy needed for standard baud rates, and the SSOP-20 package keeps the dongle footprint under 10 mm wide.
Recommended
Consumer User-Interface Board
The PIC16F721-E/SS powers consumer user-interface boards that combine a 4x4 keypad, an LED bar-graph, and a piezo buzzer. The 12-channel ADC scans a resistive keypad matrix without an external keyboard controller, the CCP drives the buzzer with PWM tones, and the 128 B EEPROM stores user preferences. The nanoWatt XLP Sleep mode lets the MCU sit idle until a key wakes it, extending battery life in remote-style controls.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F721-E/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F721-I/SS | PIC16F721T-I/SS | PIC16F720-I/SS | PIC16F720T-I/SS | PIC16F690-I/SS |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SSOP-20 (5.30 mm) | SSOP-20 (5.30 mm) - same | SSOP-20 (5.30 mm) - same | SSOP-20 (5.30 mm) - same | SSOP-20 (5.30 mm) - same | SSOP-20 (5.30 mm) - same |
| Flash Program Memory | 7 KB | 7 KB | 7 KB | 3.5 KB | 3.5 KB | 4 KB |
| SRAM | 256 B | 256 B | 256 B | 128 B | 128 B | 256 B |
| EEPROM | 128 B | 128 B | 128 B | 0 B | 0 B | 256 B |
| Maximum CPU Speed | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 20 MHz |
| Temperature Grade | -40 °C to +125 °C (E) | -40 °C to +85 °C (I) | -40 °C to +85 °C (I) | -40 °C to +85 °C (I) | -40 °C to +85 °C (I) | -40 °C to +85 °C (I) |
| nanoWatt XLP Low Power | Yes | Yes | Yes | Yes | Yes | No |
| Qty-1 Price (USD) | 1.36 | 1.30 | 1.30 | 1.10 | 1.10 | 1.45 |
Key Differentiators
- Highest-density 20-pin PIC16 with 7 KB Flash and 128 B EEPROM (vs PIC16F720-I/SS)
- nanoWatt XLP extreme-low-power Sleep (vs PIC16F690-I/SS)
- Extended -40 °C to +125 °C operating range (vs PIC16F721-I/SS)
Design Notes
Place a 100 nF ceramic decoupling capacitor within 3 mm of VDD (pin 12) and VSS (pin 11), plus a bulk 10 µF tantalum or ceramic on the same rail. AVDD/AVSS, if exposed separately, should each have a 100 nF cap. These caps suppress the supply droop that otherwise couples into the ADC reference during switching events and improves nanoWatt XLP wake-up settling.
Always include the recommended 10 kΩ pull-up on MCLR with a 100 nF cap to ground; omitting MCLR filtering makes in-circuit serial programming unreliable and exposes the part to spurious resets. Also confirm the configuration bits select the internal RC oscillator before locking the part - leaving the default HS mode without a crystal will stop the oscillator.
Route the ICSP pins (RB6/ICSPCLK and RB7/ICSDAT) as short, parallel traces without stubs so they can be probed by the MPLAB PICkit programmer on the production board. Keep the trace length under 50 mm and avoid sharing them with high-current signals. For SSOP-20 footprints, use 0.4 mm via-in-pad or 0.3 mm vias with 0.65 mm pitch escape routing to maintain signal integrity on PORTB.
Estimated: at 16 MHz the port-pin rise time is approximately 10 ns, so output edge rates produce harmonic content up to the 50 MHz range. Keep clock and CCP outputs away from the analog AN0-AN11 pins, and provide a grounded guard ring around the ADC input traces to keep digital switching noise below the 8-bit ADC's 1 LSB threshold (~20 mV at 5 V).
Compliance Information
RoHS compliant per Microchip product page; lead-free SSOP-20 package per 'SS' suffix. AEC-Q100 not qualified by default - request the automotive-grade PIC16F721T variant if AEC-Q100 is required.
