Microchip Technology ATWINC3400A-MU-Y

Overview

ATWINC3400A-MU-Y from Microchip Technology is a dual-mode IEEE 802.11b/g/n and Bluetooth 5.0 SoC network controller in a 6×6 mm QFN-48 package, integrating RF transceiver, MAC/PHY, Bluetooth LE stack, on-chip flash (1 MB), and power management. It delivers -97 dBm Wi-Fi RX sensitivity at 1 Mbps, supports SPI host interface, operates from -40°C to +85°C, and enables low-power IoT edge nodes requiring concurrent wireless connectivity.

For engineers reviewing the ATWINC3400A-MU-Y datasheet, ATWINC3400A-MU-Y pinout, ATWINC3400A-MU-Y application, or ATWINC3400A-MU-Y equivalent, this page provides verified technical context, validated pin functions, confirmed coexistence behavior between Wi-Fi and BLE, real-world power states (including 150 ms AP re-association), and accurate alternative part comparisons for embedded wireless design.

Technical Context

The ATWINC3400A-MU-Y integrates two independent Cortus APS3 32-bit processors-one dedicated to Wi-Fi MAC/PHY processing and one to Bluetooth 5.0 protocol stack execution-enabling true concurrent operation without host MCU intervention. Its hardware-accelerated A-MSDU/A-MPDU frame aggregation and block acknowledgment reduce host overhead while maintaining IEEE 802.11n throughput up to 72.2 Mbps.

It implements integrated RF front-end with PA, LNA, and T/R switch, uses 26 MHz crystal (±25 ppm calibrated) and 32.768 kHz RTC clock, and features on-chip network stack supporting TCP, UDP, DHCP, TLS, DNS, and SNTP-offloading full protocol handling from the host microcontroller.

Key Specifications

Pinout & Package

ATWINC3400A-MU-Y is housed in a 48-pin, 6×6 mm QFN package with an exposed thermal paddle (Pin 49, VSS) that must be soldered to PCB ground for thermal and electrical integrity. The package complies with JEDEC MO-220, has 0.85 mm total thickness, and supports standard lead-free reflow profiles.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-mode wireless controller applications.

Compared with ESP32-WROOM-32 and RTL8720DN, the ATWINC3400A-MU-Y offers pre-certified Bluetooth 5.0 and Wi-Fi stacks with zero-host TLS offload-reducing firmware development time by ~6 months and eliminating external flash dependency for secure boot.

Availability

ATWINC3400A-MU-Y is available at Aetrix Electronics and suitable for smart home hubs, industrial sensor nodes, medical wearables, and POS terminal peripherals requiring stable component supply across multi-year production cycles.

Supply support for ATWINC3400A-MU-Y includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog, FPGA, and connectivity solutions, serving automotive, industrial, consumer, and communications markets with ISO 9001-certified manufacturing.

The ATWINC3400 product line delivers certified, low-power dual-mode wireless controllers targeting resource-constrained IoT endpoints where regulatory certification, security offload, and minimal host dependency are critical design requirements.

FAQ

What is the primary host interface used by the ATWINC3400A-MU-Y?

The ATWINC3400A-MU-Y uses a 4-wire SPI slave interface as its primary host interface, operating up to 26 MHz with active-low SPI_SSN, bidirectional SPI_MOSI/SPI_MISO, and SPI_SCK. It also provides IRQN for asynchronous event notification and supports optional I2C master/slave and UART debug interfaces-but SPI is the only production-supported control/data path for the ATWINC3400A-MU-Y.

Does the ATWINC3400A-MU-Y include integrated flash memory, and what is its capacity?

Yes, the ATWINC3400A-MU-Y includes 1 MB of integrated flash memory used to store both Wi-Fi and Bluetooth system firmware, configuration parameters, and certificate storage. This eliminates the need for external flash in most deployments and enables secure over-the-air (OTA) updates without host MCU involvement-critical for field-deployed ATWINC3400A-MU-Y devices.

What are the clocking requirements for the ATWINC3400A-MU-Y?

The ATWINC3400A-MU-Y requires two external clocks: a 26 MHz crystal (or oscillator) connected to XO_P/XO_N pins with ±25 ppm stability after calibration, and a 32.768 kHz clock applied to the RTC pin for low-power sleep timing and Bluetooth LE power-save modes. Both clocks are mandatory-no internal RC oscillators are used for primary timing in the ATWINC3400A-MU-Y.

How does the ATWINC3400A-MU-Y handle Wi-Fi and Bluetooth coexistence?

The ATWINC3400A-MU-Y implements hardware-level coexistence logic that dynamically arbitrates RF resources between Wi-Fi and Bluetooth subsystems, preventing packet collisions during concurrent operation. This is achieved through dedicated inter-subsystem signaling and time-slicing-verified in Microchip's Bluetooth SIG and Wi-Fi Alliance certifications-and requires no host software coordination, unlike software-based coexistence schemes used in other dual-radio ICs.

Is the ATWINC3400A-MU-Y pin-compatible with earlier ATWINC1500 or ATWINC3400 variants?

No, the ATWINC3400A-MU-Y is not pin-compatible with ATWINC1500 or earlier ATWINC3400 revisions. It uses a 48-pin QFN package with different pin assignments-including relocated RFIO pins, added GPIOs, and revised power domains-requiring PCB layout changes. Migration from ATWINC1500 demands full schematic and layout revision, though software API compatibility is maintained via Microchip's WINC driver suite for the ATWINC3400A-MU-Y.