ATMEGA324A-MCHR - 8-bit AVR MCU 32KB Flash 20MHz VQFN-44 | Microchip
N.º de pieza: ATMEGA324A-MCHR ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $0 | $0,00 |
| 10 | $0 | $0,00 |
| 100 | $0 | $0,00 |
| 500 | $0 | $0,00 |
| 1.000 | $0 | $0,00 |
ATMEGA324A-MCHR Descripción general
A microcontroller (MCU) is a single integrated circuit that combines a processor core, program memory, data memory, and peripherals such as timers, UARTs, and ADCs into one chip. Microcontrollers form the lowest tier of the embedded-computing hierarchy, sitting below system-on-chip (SoC) and application processor families, and are the workhorses of embedded control, IoT nodes, and industrial automation. The ATmega324A belongs to the classic 8-bit AVR family originally developed by Atmel, now part of Microchip Technology.
Key features include the advanced RISC architecture with 131 powerful instructions, most of which execute in a single clock cycle, plus 32 general-purpose working registers. Read-while-write Flash allows self-programming for bootloaders and field firmware updates. Peripherals include a real-time counter, three flexible timers with PWM, multiple USARTs, an SPI interface, a two-wire interface (TWI/I2C), and a 10-bit ADC, enabling compact single-chip designs.
The enhanced AVR core achieves roughly 1 MIPS per MHz throughput, so at the maximum 20 MHz clock the device delivers approximately 20 MIPS. In-System Programming (ISP) over SPI permits programming without removing the chip from the board, reducing production cost. The 2KB SRAM provides adequate headroom for modest protocol stacks and control loops, while the 1KB EEPROM retains calibration data through power cycles.
Typical applications include industrial automation and sensor acquisition nodes, consumer appliances and HVAC controls, and battery-powered instrumentation where the low-power AVR core and wide voltage operation keep average current low.
Design consideration: the MCHR suffix denotes the industrial-temperature, 20 MHz VQFN-44 speed/package grade; verify the supply voltage range on the current Microchip datasheet, since distributor summaries occasionally cite different speed-grade figures.
This page synthesizes verified distributor data, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Alternativas directas para ATMEGA324A-MCHR — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con ATMEGA324A-MCHR (mismo factor de forma y huella) — difiere en Package, Flash Memory, Instruction Set, Programming, Working Registers.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
ATMEGA324PA-MCH
✅ Sustitución directa✓ En stock
$2.45 / unidad
Ver hoja de datos →ATMEGA324A-MCH
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
ATMEGA324PA-MCHR
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$2.55 / unidad
Ver hoja de datos →ATMEGA164A-MCH
✅ Sustitución directa✓ En stock
$3.55 / unidad
Ver hoja de datos →ATMEGA644A-MCH
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
ATMEGA1284-MCH
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
ATMEGA324A-MCHR Valores máximos y características eléctricas
| Core Architecture | 8-bit AVR RISC |
| Flash Memory | 32 KB ISP Flash (read-while-write) |
| EEPROM | 1 KB |
| SRAM | 2 KB |
| Frecuencia de reloj máxima | 20 MHz |
| Instructions | 131 instructions, most single-cycle |
| General Purpose I/O | 32 I/O lines |
| Working Registers | 32 x 8-bit general purpose |
| Minimum Supply Voltage | 1.80 V |
| Timers | 3 timers with PWM (real time counter included) |
| Communication Interfaces | USART, SPI, TWI (I2C) |
| ADC | 10-bit ADC |
| Encapsulado | VQFN-44 (MLF), 44QFN with exposed pad |
| Tipo de montaje | Surface Mount |
| Temperatura de funcionamiento | Industrial range (see datasheet for exact limits) |
| Programming | In-System Programmable (ISP) |
| Estado del ciclo de vida | Active |
Guía de configuración de pines de ATMEGA324A-MCHR vqfn-44 (mlf), 44qfn with exposed pad
Configuración de pines para ATMEGA324A-MCHR (encapsulado vqfn-44 (mlf), 44qfn with exposed pad). Este CI digital incluye GPIO, interfaces de comunicación (UART, SPI, I2C) y pines de alimentación. Consulte la hoja de datos del fabricante para conocer las funciones alternativas de los pines y las opciones de configuración. Esencial para el diseño de sistemas embebidos y el diseño de PCB.
No hay datos detallados de patillaje disponibles para ATMEGA324A-MCHR.
Consulte la hoja de datos para ver la configuración completa de patillas.
Aplicaciones típicas
ATMEGA324A-MCHR es adecuado para 6 aplicacións: Industrial Automation and Control, Sensor Acquisition Nodes, Consumer Appliances and HVAC, Battery-Powered Instrumentation, Communication and Interface Bridges, Motor Control and PWM Drivers.
Industrial Automation and Control
The ATMEGA324A-MCHR fits factory automation nodes because its 32 GPIO lines and three PWM-capable timers drive relays, actuators, and indicators directly, while the 20 MHz AVR core with roughly 20 MIPS throughput handles deterministic control loops. Its industrial temperature grade per Mouser 'IND' classification suits control cabinets and machinery. In a typical node, USART links to an RS-485 transceiver for Modbus communication, the 10-bit ADC samples analog process signals, and ISP Flash with read-while-write enables field firmware updates without removing the MCU from the panel, minimizing downtime.
Recomendado
Sensor Acquisition Nodes
With a 10-bit ADC, 2KB SRAM for local filtering buffers, and 32 GPIO for multiplexer control, the ATMEGA324A-MCHR is well suited for multi-channel sensor acquisition. The 1KB EEPROM stores per-unit calibration coefficients that survive power cycles, and the real-time counter supports timestamping of events. In a typical deployment the SPI interface reads external high-resolution ADCs while TWI/I2C communicates with temperature and pressure sensors; the read-while-write Flash permits logging configuration changes to program memory. The 1.80 V minimum supply supports low-voltage battery-backed designs where energy budgets are tight.
Recomendado
Consumer Appliances and HVAC
White goods, thermostats, and HVAC controllers benefit from the ATMEGA324A-MCHR's combination of 32 I/O lines for keypad matrices and display drives, PWM timers for fan and blower speed control, and 10-bit ADC for NTC temperature sensing. The AVR core's single-cycle instruction execution keeps button-scanning and PID loops responsive at modest clock rates, reducing EMI. Its ISP Flash supports bootloader-based firmware updates in the field, important for appliances with long service lives, and the VQFN-44 exposed-pad package offers good thermal performance and compact footprint for cost-sensitive two-layer control boards.
Recomendado
Battery-Powered Instrumentation
Portable instruments gain from the AVR architecture's low-power design: clock gating, multiple sleep modes, and the wide supply range beginning at 1.80 V let the ATMEGA324A-MCHR spend most of its life in idle or power-down states, waking on timer or external interrupt. The PicoPower ATMEGA324PA-MCH drop-in variant further reduces sleep current when the energy budget is critical. The 2KB SRAM holds data-logging buffers between EEPROM write cycles, and the 1KB EEPROM provides wear-leveled storage for measurement history, enabling handheld meters and dataloggers that run for months on primary cells.
Recomendado
Communication and Interface Bridges
The ATMEGA324A-MCHR includes multiple USARTs plus hardware SPI and TWI, making it an effective protocol bridge between legacy serial equipment and modern peripherals. At 20 MHz, the UART can sustain high baud rates with low CPU overhead, while the second USART simultaneously services a modem or another device. Typical designs translate between RS-232 equipment and I2C sensors, or implement Modbus RTU masters polling remote slaves. The 32KB Flash accommodates generous protocol stacks and command tables, and 131 mostly single-cycle instructions keep interrupt latency low for accurate serial timing.
Recomendado
Motor Control and PWM Drivers
Three timers with PWM output channels allow the ATMEGA324A-MCHR to generate phase-correct and fast PWM signals for DC motor speed control, servo actuation, and LED dimming. The 20 MHz clock yields fine PWM resolution at audible-frequency carrier rates, and complementary interrupt structure supports closed-loop current control using the 10-bit ADC for shunt-resistor feedback. Its industrial rating suits drive environments, and 32 GPIO lines handle limit switches, encoder inputs, and safety interlocks alongside the PWM outputs, allowing single-chip implementation of small multi-axis actuator controllers.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para ATMEGA324A-MCHR — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | ATMEGA324PA-MCH | ATMEGA164A-MCH | ATMEGA644A-MCH | ATMEGA1284-MCH |
|---|---|---|---|---|---|
| Package | VQFN-44 (MLF) | VQFN-44 (MLF) - same | VQFN-44 (MLF) - same | VQFN-44 (MLF) - same | VQFN-44 (MLF) - same |
| Brand | Microchip Technology (Atmel) | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 32 KB | 32 KB | 16 KB | 64 KB | 128 KB |
| SRAM | 2 KB | 2 KB | 1 KB | 4 KB | 16 KB |
| EEPROM | 1 KB | 1 KB | 512 B | 2 KB | 4 KB |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| GPIO Count | 32 | 32 | 32 | 32 | 32 |
| Low Power Feature | Standard AVR power modes | PicoPower (lower sleep current) | Standard AVR power modes | Standard AVR power modes | picoPower variants available |
Diferenciadores clave
- Full 32KB Flash at 20 MHz in the classic mega324 pinout (frente a ATMEGA164A-MCH)
- More I/O and a second USART than the popular mega328 in small packages (frente a ATMEGA328PB-MU)
- Pin-compatible upgrade path to 128KB (frente a ATMEGA1284-MCH)
- Tape-and-reel packaging for automated assembly (frente a ATMEGA324A-MCH)
Notas de diseño
The MCHR VQFN-44 (MLF) package includes an exposed die pad on the underside that must be soldered to a ground plane for both mechanical reliability and thermal dissipation. Use a solder paste window-pane pattern on the pad, with several small vias to the ground plane to wick excess solder. Because the 0.5 mm or 0.8 mm pitch QFN lands leave little excess solder, stencil aperture design should be verified with a first-article inspection before volume assembly. Pin 1 is identified by the chamfered corner - confirm orientation in pick-and-place data.
Decouple VCC and AVCC independently: place a 100 nF ceramic capacitor within 2-3 mm of each supply pin plus one bulk 4.7-10 uF capacitor per board. Tie AVCC to VCC through an RC filter (10 ohm resistor and 100 nF capacitor) when ADC accuracy matters, keeping analog grounds star-connected to the exposed pad. Ensure the supply stays within the datasheet operating range across brown-out conditions, and enable the internal brown-out detector via fuses so the MCU resets cleanly rather than corrupting EEPROM during supply dips.
Do not confuse speed grades when sourcing: distributor summaries occasionally quote 16 MHz / 4.5-5.5 V figures that belong to a different suffix of the mega324 family, while the -MCHR is characterized at 20 MHz. Verify the exact operating voltage range against the current Microchip ATmega324A datasheet before finalizing power supply design. Also remember PB6/PB7 double as XTAL1/XTAL2 - if an external crystal is fitted, those two GPIOs are lost, reducing usable I/O to 30 pins, so plan pin budgets accordingly.
Route the ISP programming header (MOSI, MISO, SCK, RESET, VCC, GND) as a 2x3 100 mil connector early in layout; retro-fitting programming access is a common rework source. Keep the crystal within a few millimeters of PB6/PB7 with short ground-guard traces, and series-terminate long SPI or clock traces to control ringing. Avoid routing fast switching traces (PWM outputs, SPI SCK) under the ADC input traces to preserve 10-bit converter accuracy.
Información de cumplimiento
Compliance statuses were not stated in the verified web data; consult the Microchip product page and environmental datasheet for RoHS/REACH confirmation.
