Microchip Technology ATA5824C-PLQW-1

Overview

ATA5824C-PLQW-1 from Microchip Technology (formerly Atmel) is a highly integrated UHF ASK/FSK half-duplex transceiver in a 7mm × 7mm QFN48 package, operating at 433.92MHz with –105.5dBm FSK sensitivity at 20Kbit/s and 10.5mA supply current in RX/TX mode at 3V. It integrates fractional-N synthesizer, low-IF receiver (226kHz IF), RSSI, SPI interface (500kBit/s), and supports automotive keyless entry and tire pressure monitoring systems.

For engineers reviewing the ATA5824C-PLQW-1 datasheet, ATA5824C-PLQW-1 pinout, ATA5824C-PLQW-1 application, or ATA5824C-PLQW-1 equivalent, key selection considerations include its 433.92MHz band support, dual ASK/FSK modulation, programmable output power (0–10dBm), ultra-low power-down current (<10nA), and integrated crystal capacitors enabling minimal external components in RKE/TPM designs.

Technical Context

The ATA5824C-PLQW-1 implements a fully integrated low-IF receiver architecture with 226kHz intermediate frequency, 30dB image rejection, and 220kHz system bandwidth-optimized for compatibility with ATA5756/ATA5757 TPM transmitters. Its fractional-N synthesizer provides 800Hz RF resolution and compensates XTAL tolerances, enabling stable multi-channel operation without external VCO/PLL components.

Transmit functionality uses closed-loop FSK modulation with high PLL bandwidth and >60dB isolation between PLL and PA. The device supports Manchester-encoded data rates from 1–20Kbit/s (FSK) and 1–10Kbit/s (ASK), with configurable self-polling, FIFO-RAM buffering, and protocol handling to offload microcontroller tasks in fast challenge-response systems.

Key Specifications

Pinout & Package

Package: 7mm × 7mm QFN48 with exposed die pad (GND). Pinout validated per Atmel/Microchip datasheet 4829G–RKE–01/15.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar UHF ASK/FSK transceiver applications.

Compared with SI4432-B1B-FMR and AX5043-DQ48, the ATA5824C-PLQW-1 delivers superior integration for automotive RKE/TPM-embedding crystal capacitors, XTO start-up, and ASK/FSK dual-mode demodulation-while achieving lowest system-level component count and longest battery life in compact form factor.

Availability

ATA5824C-PLQW-1 is available at Aetrix Electronics and suitable for automotive keyless entry, tire pressure monitoring systems, and remote control applications requiring stable component supply across extended temperature ranges (–40°C to +105°C) and long product lifecycles.

Supply support for ATA5824C-PLQW-1 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 acquired Atmel in 2016 and maintains full support for the ATA5824 product line, delivering high-reliability mixed-signal ICs for automotive, industrial, and IoT markets.

The ATA5824C-PLQW-1 belongs to Microchip's UHF transceiver family designed specifically for secure, low-power wireless access control and telemetry in automotive and industrial environments-emphasizing RF integration, protocol offload, and AEC-Q100 compliance.

FAQ

What is the operating frequency range supported by the ATA5824C-PLQW-1?

The ATA5824C-PLQW-1 operates in the 433.92MHz ISM band and is configured for this frequency via the 433_N868 pin. It does not support 868MHz operation in this variant. The device achieves stable performance across this band using its integrated fractional-N synthesizer, which compensates for crystal tolerances and eliminates need for external VCO or PLL components-enabling direct use with standard 13.25311MHz crystals in automotive RKE and TPM systems.

How does the ATA5824C-PLQW-1 achieve ultra-low power consumption in battery-powered applications?

The ATA5824C-PLQW-1 achieves <10nA power-down current through dedicated low-leakage circuit design and dual wake-up inputs (PWR_ON and N_PWR_ON), allowing immediate exit from deep sleep on button press or external event. In active RX/TX mode, it draws only 10.5mA at 3V-optimized via efficient PA (38% efficiency at 433.92MHz/10dBm) and low-IF architecture that avoids power-hungry SAW filters. This enables multi-year operation on CR2032 coin cells in key fobs and TPMS sensors.

Can the ATA5824C-PLQW-1 interface directly with an 8-bit microcontroller without external level-shifting?

Yes, the ATA5824C-PLQW-1 supports direct SPI interfacing with 8-bit microcontrollers via its VSINT pin, which supplies the digital I/O voltage (1.8V–3.6V) to match MCU logic levels. Its SPI interface operates up to 500kBit/s and includes dedicated CS, SCK, SDI_TMDI, and SDO_TMDO pins-eliminating need for level shifters. Additionally, the integrated CLK output (~4.5MHz) can drive the MCU's external clock input, removing requirement for separate oscillator circuitry in cost-sensitive RKE/TPM designs.

What is the role of the CDEM capacitor on the ATA5824C-PLQW-1?

The CDEM capacitor (connected to pin 37) sets the lower cut-off frequency of the internal data filter, directly influencing ASK/FSK demodulation robustness against low-frequency noise and baseline wander. A typical value of 15nF establishes a high-pass characteristic optimized for Manchester-encoded signals at 1–20Kbit/s. Adjusting CDEM allows fine-tuning of filter response to match specific modulation schemes or channel impairments-critical for maintaining BER <10⁻³ in electrically noisy automotive environments where the ATA5824C-PLQW-1 is deployed.

Does the ATA5824C-PLQW-1 require external crystal load capacitors?

No, the ATA5824C-PLQW-1 integrates 9pF load capacitors internally on XTAL1 and XTAL2 pins, eliminating need for external crystal load capacitors. This reduces BOM count and layout complexity-especially valuable in space-constrained key fob designs. The device is specified for use with a 13.25311MHz fundamental-mode crystal, and its XTO start-up circuit ensures reliable oscillation even with worst-case crystal impedance (>–1.5kΩ), supporting robust operation across temperature and voltage extremes.