ATMEGA168PB-AUR - 16KB AVR MCU 20MHz TQFP-32 | Microchip
MPN: ATMEGA168PB-AUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.35 | $2.35 |
| 10 | $2.12 | $21.20 |
| 100 | $1.89 | $189.00 |
| 500 | $1.72 | $860.00 |
| 1,000 | $1.58 | $1,580.00 |
ATMEGA168PB-AUR Overview
An AVR microcontroller is a single-chip computer built on the enhanced RISC architecture originally developed by Atmel (now Microchip). It executes most instructions in a single clock cycle, achieving throughput approaching 1 MIPS per MHz, which lets designers trade processing speed against power consumption. Within the product taxonomy, the ATmega168PB sits at microcontroller -> 8-bit MCU -> embedded processor -> semiconductor IC, and it is the mid-memory member of the pin-compatible ATmega48PB/88PB/168PB trio.
Key features include 16 KB of self-programmable flash with read-while-write capability, 512 bytes of EEPROM for non-volatile parameter storage, 1 KB of SRAM, 32 general-purpose working registers, and three flexible timer/counters with compare modes. The device integrates Core Independent Peripherals (CIPs) and picoPower technology, enabling true 1.8 V operation and extremely low sleep currents for battery-powered designs.
The ATmega168PB architecture pairs the AVR core with a rich peripheral set: USART with wake-up on start-of-frame, SPI, TWI (I2C), a 10-bit ADC, internal and external interrupts, and a calibrated RC oscillator. The 'PB' generation adds the Peripheral Touch Controller (PTC) and improved serial communication features over the earlier 'PA' generation, while retaining the same TQFP-32 footprint.
Typical applications include Arduino-compatible development boards, industrial sensor nodes, battery-powered IoT endpoints, motor control front-ends, and consumer white goods. The 1.8 V to 5.5 V supply range allows direct operation from single-cell Li-Ion or 3xAA battery packs without an intermediate regulator.
When designing with this device, decouple every VCC pin with a 100 nF ceramic capacitor placed within a few millimeters of the pin, and keep the AVCC filter inductor away from high-current switching nodes. The reset pin should be pulled high through 10 kOhm and protected with a 100 nF capacitor to ground.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, giving engineers a single reference for selection, replacement, and layout decisions.
Drop-in alternatives for ATMEGA168PB-AUR 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 ATMEGA168PB-AUR (same form factor and footprint) β differing in Working Registers, Communication Interfaces, Instructions, Packaging, Throughput.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA168PB-AU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA88PB-AU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA48PB-AU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA168PA-AU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA168PA-ANR
β Drop-Inβ In Stock
$1.44 / Unit
View Datasheet βATMEGA168A-AUR
β Drop-Inβ In Stock
$1.45 / Unit
View Datasheet βATMEGA168PB-AUR Maximum Ratings & Electrical Characteristics
| Core Processor | AVR 8-bit RISC |
| Program Memory Size | 16 KB (8K x 16) ISP Flash |
| EEPROM Size | 512 B |
| SRAM Size | 1 KB |
| Maximum Clock Frequency | 20 MHz |
| Throughput | Approaching 1 MIPS per MHz |
| General Purpose I/O Lines | 27 |
| Working Registers | 32 general-purpose |
| Supply Voltage Range | 1.8 V to 5.5 V |
| Operating Temperature | -40 C to +85 C |
| Package / Case | 32-TQFP (7x7 mm) |
| Mounting Type | Surface Mount |
| ADC Resolution | 10-bit |
| Timer/Counters | Three flexible timer/counters with compare modes |
| Communication Interfaces | USART, SPI, TWI (I2C) |
| Packaging | Tape & Reel (AUR suffix) |
| RoHS Status | Compliant (Pb-free, Halide-free, fully Green) |
| Series | AVR ATmega, Functional Safety (FuSa) |
ATMEGA168PB-AUR Pin Configuration
| Pin 1 | PD3 β Port D, bit 3 (also INT1, OC2B, USART1 TXD) |
| Pin 2 | PD4 β Port D, bit 4 (also T0, XCK1, PCINT20) |
| Pin 3 | GND β Ground |
| Pin 4 | VCC β Digital supply voltage |
| Pin 5 | GND β Ground |
| Pin 6 | VCC β Digital supply voltage |
| Pin 7 | PB6 β Port B, bit 6 (also XTAL1/TOSC1, PCINT6) |
| Pin 8 | PB7 β Port B, bit 7 (also XTAL2/TOSC2, PCINT7) |
| Pin 9 | PD5 β Port D, bit 5 (also OC0B, T1, USART1 TXD) |
| Pin 10 | PD6 β Port D, bit 6 (also OC0A, AIN0, USART1 RXD) |
| Pin 11 | PD7 β Port D, bit 7 (also AIN1, PCINT23) |
| Pin 12 | PB0 β Port B, bit 0 (also ICP1, CLKO, PCINT0) |
| Pin 13 | PB1 β Port B, bit 1 (also OC1A, PCINT1) |
| Pin 14 | PB2 β Port B, bit 2 (also OC1B, PCINT2) |
| Pin 15 | PB3 β Port B, bit 3 (also OC2A, MOSI, PCINT3) |
| Pin 16 | PB4 β Port B, bit 4 (also MISO, PCINT4) |
| Pin 17 | PB5 β Port B, bit 5 (also SCK, PCINT5) |
| Pin 18 | AVCC β Analog supply voltage for ADC |
| Pin 19 | ADC6 β Analog-to-digital converter input 6 |
| Pin 20 | AREF β Analog reference voltage for ADC |
| Pin 21 | GND β Ground |
| Pin 22 | ADC7 β Analog-to-digital converter input 7 |
| Pin 23 | PC0 β Port C, bit 0 (also ADC0, PCINT8) |
| Pin 24 | PC1 β Port C, bit 1 (also ADC1, PCINT9) |
| Pin 25 | PC2 β Port C, bit 2 (also ADC2, PCINT10) |
| Pin 26 | PC3 β Port C, bit 3 (also ADC3, PCINT11) |
| Pin 27 | PC4 β Port C, bit 4 (also ADC4, SDA, PCINT12) |
| Pin 28 | PC5 β Port C, bit 5 (also ADC5, SCL, PCINT13) |
| Pin 29 | PC6 β Port C, bit 6 (also RESET, PCINT14) |
| Pin 30 | PD0 β Port D, bit 0 (also RXD, PCINT16) |
| Pin 31 | PD1 β Port D, bit 1 (also TXD, PCINT17) |
| Pin 32 | PD2 β Port D, bit 2 (also INT0, PCINT18) |
Typical Applications
ATMEGA168PB-AUR is suitable for 6 applications: Arduino-Compatible Development Boards, Battery-Powered IoT Sensor Nodes, Industrial Sensor and Control Nodes, Consumer White Goods and Appliances, Motor Control Front-Ends, Capacitive Touch User Interfaces.
Arduino-Compatible Development Boards
The ATMEGA168PB-AUR is an ideal host MCU for Arduino-compatible development boards because its 16 KB flash and 1 KB SRAM comfortably fit the Arduino bootloader plus typical sketches, while the 20 MHz maximum clock preserves standard Arduino timing. The 32-pin TQFP footprint matches the classic ATmega168/328 board layout, so existing shield ecosystems remain compatible. The device is supported by the MiniCore Arduino hardware package, which covers ATmega8 through ATmega328PB. Placed as the main controller with a 16 MHz crystal on XTAL1/XTAL2 and a 100 nF decoupling capacitor on each VCC pin, it delivers deterministic 1 MIPS/MHz execution. The trade-off versus the ATmega328PB is reduced flash, so sketches using large libraries may need optimization.
Recommended
Battery-Powered IoT Sensor Nodes
The ATMEGA168PB-AUR fits battery-powered IoT sensor nodes because its picoPower technology supports true 1.8 V operation with very low sleep currents, and the 1.8 V to 5.5 V supply range allows direct connection to a single-cell Li-Ion battery without an intermediate regulator. In a typical node, the MCU wakes from power-down on a timer or external interrupt, samples a sensor through the 10-bit ADC, and transmits via USART or SPI before returning to sleep. The 512 B EEPROM stores calibration coefficients and network credentials without external memory. The trade-off is that 1 KB SRAM limits large data buffers, so designs should stream samples rather than batch them. Decouple AVCC with a 100 nF capacitor and a 10 uH inductor for clean ADC readings.
Recommended
Industrial Sensor and Control Nodes
The ATMEGA168PB-AUR suits industrial sensor and control nodes because its -40 C to +85 C operating range and 5 V-tolerant I/O interface directly with industrial sensors and 24 V field wiring through optocouplers. The three flexible timer/counters with compare modes generate precise PWM for valve or heater control, while the USART with wake-up on start-of-frame supports Modbus-style multidrop networks. The 27 GPIO lines provide ample headroom for status LEDs, relays, and DIP switches. In a typical node, the MCU runs a 10 ms control loop, reads analog inputs through the 10-bit ADC, and drives outputs via the timer PWM channels. The trade-off versus a 32-bit MCU is lower math throughput, so complex control algorithms should be simplified.
Recommended
Consumer White Goods and Appliances
The ATMEGA168PB-AUR is well suited to consumer white goods such as washing machines, dishwashers, and microwave ovens because the 16 KB flash holds appliance control firmware, the 512 B EEPROM stores user settings across power cycles, and the 27 GPIO lines drive relays, triacs, and seven-segment displays. The Peripheral Touch Controller enables capacitive touch button panels without external touch ICs, reducing BOM cost. Operating from a 5 V rail, the device interfaces directly with triac drivers and buzzer circuits. In a typical design, the MCU runs a state machine that sequences motor, heater, and valve outputs while monitoring door and water-level sensors. The trade-off is that 1 KB SRAM limits complex UI state, so display logic should be kept simple.
Recommended
Motor Control Front-Ends
The ATMEGA168PB-AUR serves as a motor control front-end because its three flexible timer/counters with compare modes generate complementary PWM waveforms for H-bridge and three-phase inverter gate drivers, while the 10-bit ADC samples current-shunt and back-EMF signals for closed-loop commutation. The 20 MHz clock provides adequate loop bandwidth for brushed DC and low-pole-count BLDC motors. In a typical design, the MCU runs a 20 kHz PWM carrier with ADC sampling synchronized to the PWM trough to minimize switching noise, and the USART reports speed and fault status to a host controller. The trade-off versus a dedicated motor-control MCU is the absence of hardware dead-time insertion, so external gate drivers with built-in dead time are recommended.
Recommended
Capacitive Touch User Interfaces
The ATMEGA168PB-AUR is an excellent choice for capacitive touch user interfaces because the PB generation integrates a Peripheral Touch Controller (PTC) that supports mutual-capacitance and self-capacitance sensing without external touch controller ICs. The PTC handles up to 27 channels, matching the device's GPIO count, and works through glass or plastic overlays up to several millimeters thick. In a typical design, the MCU scans touch electrodes during idle time, filters the signal in firmware, and drives LEDs or relays in response, all while maintaining a low average current for battery operation. The trade-off is that touch sensitivity depends on PCB layout, so electrode traces should be kept short and away from switching nodes. The 16 KB flash accommodates touch library plus application code.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA168PB-AUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA168PB-AU | ATMEGA88PB-AU | ATMEGA48PB-AU | ATMEGA168PA-AU |
|---|---|---|---|---|---|
| Package | 32-TQFP (7x7 mm) | 32-TQFP (7x7 mm) - same | 32-TQFP (7x7 mm) - same | 32-TQFP (7x7 mm) - same | 32-TQFP (7x7 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 16 KB (8K x 16) | 16 KB | 8 KB | 4 KB | 16 KB |
| SRAM | 1 KB | 1 KB | 512 B | 512 B | 1 KB |
| EEPROM | 512 B | 512 B | 512 B | 256 B | 512 B |
| Maximum Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| GPIO Lines | 27 | 27 | 27 | 27 | 27 |
| Peripheral Touch Controller | Yes (PB generation) | Yes | Yes | Yes | No |
| Packaging | Tape & Reel (AUR) | Tray | Tray | Tray | Tray |
Key Differentiators
- PB-generation Core Independent Peripherals and PTC (vs ATMEGA168PA-AU)
- Double the flash and SRAM of the ATMEGA88PB-AU (vs ATMEGA88PB-AU)
- Quadruple the flash of the ATMEGA48PB-AU (vs ATMEGA48PB-AU)
- Tape-and-reel packaging for automated assembly (vs ATMEGA168PB-AU)
Design Notes
Decouple every VCC pin (pins 4 and 6) with a 100 nF ceramic capacitor placed within a few millimeters of the pin, and add a 10 uF bulk capacitor near the package. For the analog supply, connect AVCC (pin 18) through a 10 uH inductor or ferrite bead from VCC and decouple with 100 nF to GND. AREF (pin 20) should be decoupled with 100 nF to GND when using the internal reference, or driven from a low-impedance external reference for ratiometric ADC measurements.
Keep the crystal or resonator connected to XTAL1 (pin 7) and XTAL2 (pin 8) as close to the MCU as possible, with load capacitors sized per the crystal datasheet (typically 12-22 pF) and a solid ground plane beneath. Route crystal traces away from switching nodes and GPIO toggling at high frequency. The RESET pin (PC6, pin 29) should be pulled high through 10 kOhm to VCC and protected with a 100 nF capacitor to GND for noise immunity.
Do not leave the AVCC pin unconnected or share its decoupling with digital VCC without filtering, as this degrades ADC accuracy. When migrating from the ATmega168PA to the ATmega168PB, verify pin function changes per the Microchip migration document, since the PB generation introduces alternate pin configurations. Also confirm that the ISP programming header uses the correct SCK, MISO, and MOSI pins (PB5, PB4, PB3) and that the reset line is not loaded by external circuitry during programming.
Estimated: The ATMEGA168PB-AUR in TQFP-32 has a typical thermal resistance (theta_JA) of approximately 60-80 C/W depending on PCB copper area. At 5.5 V and 10 mA core current, power dissipation is about 55 mW, giving a junction rise of roughly 3-4 C above ambient - well within the -40 C to +85 C operating range. No heatsinking is required for normal operation; ensure adequate copper pour on the ground pins for thermal relief.
Compliance Information
Microchip documentation states Pb-free packaging complies with the European RoHS directive and is Halide-free and fully Green. AEC-Q100 qualification is not stated for this part; the ATMEGA168PB-AUR is an industrial-grade device rated -40 C to +85 C.
