ATMEGA169PA-MCHR - AVR 8-bit MCU 16KB LCD 64-QFN | Microchip
MPN: ATMEGA169PA-MCHR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.95 | $3.95 |
| 10 | $3.55 | $35.50 |
| 100 | $3.12 | $312.00 |
| 500 | $2.85 | $1,425.00 |
| 1,000 | $2.58 | $2,580.00 |
ATMEGA169PA-MCHR Overview
A microcontroller unit (MCU) is a single-chip computer that integrates a processor core, memory, and peripherals into one package, sitting at the lowest level of the embedded-systems hierarchy (MCU -> embedded processor -> SoC). The ATmega family is Microchip's classic 8-bit AVR RISC line, executing most instructions in a single clock cycle with 32 general-purpose working registers. This part adds an on-chip segment LCD driver, a peripheral rare among modern 8-bit MCUs, which makes the ATmega169 sub-family a long-standing choice for battery-powered metering and display products.
Key features include the picoPower technology set for ultra-low sleep-mode consumption, read-while-write flash for in-system firmware updates, 54 general-purpose I/O lines, and a rich peripheral set with USART, SPI, two-wire interface (I2C), analog comparator, 10-bit ADC, and multiple power-saving idle and power-down modes. The -MCHR suffix denotes the 64-QFN (7x7 mm, exposed pad) package, tape-and-reel packing, and industrial temperature range.
Architecturally, the AVR core pairs a Harvard memory structure with single-cycle execution, and the picoPower options (power-down, power-save, standby) let firmware trade wake-up latency against nanoamp-level sleep current. The LCD driver drives multiplexed segment/glass configurations directly, removing an external LCD driver IC from the bill of materials.
Typical applications include battery-operated utility meters with LCD displays, handheld industrial instruments, thermostat and HVAC control panels, and consumer appliances requiring a segment display and long battery life.
Design consideration: the -PA picoPower variant is code-compatible with earlier ATmega169 parts, but sleep currents differ, so verify the power budget against the picoPower datasheet figures and decouple the 64-QFN exposed pad to ground for thermal and noise performance.
This page synthesizes distributor pricing, drop-in alternatives, design notes, and FAQ content not found in the manufacturer datasheet alone.
Drop-in alternatives for ATMEGA169PA-MCHR 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 ATMEGA169PA-MCHR (same form factor and footprint) β differing in Flash Memory, General Purpose I/O, Maximum Clock Frequency, Packaging, Working Registers.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA169PA-MCH
β Drop-Inβ In Stock
$1.68 / Unit
View Datasheet βATMEGA169A-MCH
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA329P-MCHR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA329PA-MCH
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA329P-MCH
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA169PA-MCHR Maximum Ratings & Electrical Characteristics
| Core Processor | AVR 8-bit RISC |
| Core Size | 8-bit |
| Maximum Clock Frequency | 16 MHz |
| Flash Memory | 16 KB (8K x 16), ISP, read-while-write |
| EEPROM | 512 B |
| SRAM | 1 KB |
| General Purpose I/O | 54 lines (69 total pins incl. LCD segments) |
| Working Registers | 32 general purpose |
| LCD Controller | Integrated segment LCD driver |
| Low Power Technology | picoPower |
| Supply Voltage | 2.5 V / 3.3 V / 5 V (per cross-reference data) |
| Package | 64-QFN (7x7 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (R suffix) |
| Communication Interfaces | USART, SPI, TWI (I2C) |
| RoHS Status | Compliant |
ATMEGA169PA-MCHR 64-qfn (7x7 mm) with exposed pad Pin Configuration Guide
Pin configuration for ATMEGA169PA-MCHR (64-qfn (7x7 mm) with exposed pad package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for ATMEGA169PA-MCHR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA169PA-MCHR is suitable for 6 applications: Battery-Powered Utility Meters, Handheld Industrial Instruments, Thermostats and HVAC Control Panels, Consumer Appliance Panels, Security and Access Control Devices, IoT Sensor Nodes with Segment Display.
Battery-Powered Utility Meters
Utility meters (electricity, water, gas sub-meters) require a multiplexed segment LCD, long-life battery operation, and non-volatile storage of calibration data. The ATMEGA169PA-MCHR fits precisely: its integrated LCD driver drives the meter glass directly, its picoPower power-down and power-save modes extend battery life to multi-year service intervals, and the 512 B EEPROM stores metrology calibration constants across power loss. The 16 MHz AVR core executes most instructions in a single cycle, so a metering firmware loop can complete quickly and return the device to sleep. Placed with the LCD glass on SEG/SUP pins and a low-frequency 32 kHz watch crystal in power-save mode, the MCU keeps a real-time counter at minimal current while wake-up on demand handles measurement bursts over the USART or TWI interface.
Recommended
Handheld Industrial Instruments
Handheld instruments such as panel meters, gauges, and portable testers benefit from the ATMEGA169PA-MCHR's combination of a segment display driver, 10-bit ADC input, and single-cycle 16 MHz RISC core. The LCD driver renders readings without a companion display controller, saving board area inside compact handheld enclosures, while the ADC digitizes sensor signals directly. PicoPower sleep modes conserve the battery pack between measurements, an essential trait for field tools used intermittently. The 54 general-purpose I/O lines support keypad scanning, relay or buzzer control, and serial communication to a PC or logger over the USART. Designers typically clock the part from an internal RC oscillator for cost savings and switch to the external 16 MHz crystal only for timing-critical measurement windows, balancing accuracy against power and component count.
Recommended
Thermostats and HVAC Control Panels
Room thermostats and HVAC zone controllers pair a segment LCD with temperature sensing, setpoint keys, and relay or valve actuation - a workload well matched to the ATMEGA169PA-MCHR. The on-chip LCD driver displays temperature, mode, and schedule information; the EEPROM retains user schedules and calibration through power outages; and picoPower power-down keeps standby draw low in battery-powered wall units. The 16 KB flash accommodates full control firmware including PI loops for modulation valves, and the TWI interface connects external temperature or humidity sensors. In relay-driven designs, the MCU's timer PWM peripherals stage actuator transitions while the core stays mostly asleep. The exposed-pad 64-QFN grounds through a small thermal pour, adequate because an 8-bit MCU at typical control-loop duty cycles dissipates only milliwatts.
Recommended
Consumer Appliance Panels
White-goods and small-appliance control panels frequently use segment LCDs for cycle status, time, and fault codes. The ATMEGA169PA-MCHR consolidates display driving, key scanning, buzzer control, and load switching into one 16 MHz AVR chip, reducing bill-of-materials count relative to a generic MCU plus LCD driver. Its 16 KB flash holds both the UI state machine and the appliance control logic, while the EEPROM logs fault history and usage counters. PicoPower standby modes support energy-label compliance targets by minimizing off-state consumption. Robust AVR I/O tolerates the noisy electromechanical environment of appliances, and the USART provides a factory test port. Layout practice: route LCD segment lines away from relay and triac drive traces on the display PCB to prevent ghost segments from capacitive coupling.
Recommended
Security and Access Control Devices
Access keypads, door controllers, and small security panels need a compact MCU that drives a status display, scans a key matrix, and communicates with a central controller. The ATMEGA169PA-MCHR covers all three roles: its LCD driver shows entry prompts and alarms, its abundant GPIO handles the key matrix and LED indicators, and the USART or TWI links to RFID readers or panel backhauls. The 512 B EEPROM stores user codes and event counters securely through power cycles, and read-while-write flash allows field firmware updates without halting the display refresh. With a 16 MHz single-cycle core, scan-and-display loops complete in microseconds, so the part can idle in power-save between events. Battery-backed variants exploit picoPower modes to survive mains outage for days on a small cell.
Recommended
IoT Sensor Nodes with Segment Display
Low-cost IoT sensor nodes that report a measured value locally on a segment LCD and upstream over a serial radio module fit the ATMEGA169PA-MCHR well. The MCU's picoPower sleep architecture dominates node lifetime: typical designs spend over 99 percent of time in power-down, waking on a timer or external interrupt to sample the sensor via the 10-bit ADC, update the LCD, and push data through the USART to a radio. The 16 KB flash stores the sampling stack plus lightweight protocol handling, and EEPROM keeps device identity and last-known calibration. Power budgeting practice: use the internal RC oscillator in sleep domains and the crystal only for the 16 MHz active bursts, and budget the LCD driver duty cycle since multiplexed glass drive is often the largest active-mode consumer after the radio.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA169PA-MCHR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA169PA-MCH | ATMEGA169A-MCH | ATMEGA329P-MCHR |
|---|---|---|---|---|
| Package | 64-QFN (7x7 mm) | 64-QFN (7x7 mm) - same | 64-QFN (7x7 mm) - same | 64-QFN (7x7 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 16 KB | 16 KB | 16 KB | 32 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 2 KB |
| EEPROM | 512 B | 512 B | 512 B | 1 KB |
| picoPower Low Sleep Current | Yes | Yes | No (standard ATmega169A) | Yes |
| LCD Controller | Yes | Yes | Yes | Yes |
| Max Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 16 MHz |
| Packing | Tape & Reel (R) | Tray / cut tape | Tray / cut tape | Tape & Reel |
Key Differentiators
- picoPower sleep modes for lowest battery drain (vs ATMEGA169A-MCH)
- 16 KB flash at the lowest cost point of the LCD AVR family (vs ATMEGA329P-MCHR)
- Tape-and-reel packing for automated assembly (vs ATMEGA169PA-MCH)
Design Notes
For battery designs, exploit the picoPower modes explicitly: configure unused I/O as inputs with pull-ups or as outputs driven low before entering power-down, because floating pins increase leakage. Use the 32 kHz watch crystal in power-save mode for timekeeping, and reserve the 16 MHz crystal for active bursts. Estimated: in a meter waking once per second for 2 ms of active work, duty cycle is 0.2 percent, so average current is dominated by sleep-mode current - verify actual figures in the manufacturer datasheet for the -PA picoPower variant.
Solder the 64-QFN exposed pad to a solid ground pour with an array of thermal vias; this provides both the device ground return and thermal relief. Decouple VCC and AVCC with 100 nF ceramics placed within 2 mm of the pins, plus a 10 uF bulk capacitor near the supply entry. Route LCD segment lines with spacing from switching loads, and keep the crystal traces short and guarded by ground. On 0.5 mm-pitch QFN pads, specify NSMD pad geometry for reliable solder joints.
AVR maximum clock frequency derates with supply voltage - do not run 16 MHz at the bottom of the voltage range without checking the VCC-versus-fMAX curve in the datasheet. Bring SPI programming signals (MOSI, MISO, SCK, RESET) to accessible test points, since QFN pins cannot be probed in circuit. When substituting ATMEGA169A-MCH (non-picoPower) for this part, re-measure sleep current; code is compatible but the power budget may shift. Confirm LCD biasing capacitor requirements against the datasheet for your glass configuration.
Compliance Information
RoHS compliant per distributor listings (DigiKey/Mouser) for the Microchip -MCH green/lead-free 64-QFN package. REACH and conflict-minerals declarations should be obtained from Microchip's quality portal for the specific date code.
