Hw-044 - Datasheet

HW-044 Datasheet: Complete Pinout, Specifications, and Application Guide

Introduction

The HW-044 is a highly popular, inexpensive, and versatile breakout board for the MAX98357 audio amplifier IC. If you are searching for the hw-044 datasheet, you are likely working on an embedded audio project involving an Arduino, ESP32, ESP8266, Raspberry Pi, or any other microcontroller that supports I²S (Inter-IC Sound) audio.

Unlike traditional analog amplifiers (like the LM386), the HW-044 uses a digital I²S input, which results in superior audio quality, reduced noise, and simpler wiring. This article serves as a comprehensive datasheet and practical guide, covering everything from electrical characteristics and pinout to schematic integration and troubleshooting.

Electrical characteristics (typical assumptions)

  • Supply voltage (VCC): 1.8–3.6 V; recommended 3.3 V.
  • I/O voltage tolerance: up to VCC (not 5 V tolerant unless specified).
  • Quiescent current (standby): 2–10 µA.
  • Active current (continuous sampling at 100 Hz): 0.8–1.5 mA.
  • Sleep mode wake-up: <1 ms.
  • ADC input range: 0–VREF (VREF = VCC internally or tied to an external 1.2 V ref; specify).
  • Digital logic high threshold: ≥0.7·VCC; low ≤0.3·VCC.
  • ESD: ±2 kV HBM on all pins (recommend external protection for harsh environments).

Status LEDs:

  • PWR LED (Red): Indicates power is applied.
  • SD LED (Optional): Lights when audio data is detected.

Pinout Table (Top View, Label Side Up)

| Pin Label | Function | Description | |-----------|----------|-------------| | VIN | Power Input | 2.7V – 5.5V DC. 5V recommended for maximum output power. | | GND | Ground | Connect to system ground. | | BCLK | Bit Clock | Also known as BCLK or SCK. I²S serial clock. | | LRC | Left/Right Clock | Also known as WS or FS. Frame sync for I²S. | | DIN | Data Input | Serial audio data line (I²S data). | | GAIN | Gain Select | Strapping pin (see gain settings below). | | SD_MODE | Shutdown / Mode | High = normal operation, Low = shutdown. Also used for channel/chip address. | | SPK+ / SPK- | Speaker Output | Connect to 4Ω – 8Ω speaker. Do NOT connect to ground. | hw-044 datasheet

Note: On some HW-044 revisions, the GAIN and SD_MODE pins may be unlabeled or swapped. Always check the silkscreen on your specific board.

Functional description

The HW-044 integrates a precision analogue front-end, A/D converter, microcontroller-based signal processing, and an I2C peripheral for host communication. The front-end conditions the transducer element (e.g., resistive, capacitive or MEMS sensor), applies excitation where needed, filters the signal (anti-aliasing), then digitizes with a high-resolution sigma-delta ADC. On-chip firmware performs temperature compensation, linearization, optional averaging, and error-checking. Data are presented over I2C as signed 16-bit words with a small status register. An interrupt/alert pin signals threshold crossings or data-ready.

How Does the HW-044 Work?

The HW-044 works on the principle of Quadrature Encoding. Inside the knob, a disk with contact patterns rotates past two contact sensors (A and B). Electrical characteristics (typical assumptions)

When you turn the knob, the module outputs two square wave signals (CLK and DT) that are 90 degrees out of phase. By comparing the state of these two pins, the microcontroller can determine the direction of rotation.

  • Clockwise Rotation: The CLK signal leads the DT signal.
  • Counter-Clockwise Rotation: The DT signal leads the CLK signal.

By counting the pulses, you can track exactly how many "steps" the knob has turned.

6. Typical Connections (to Arduino Uno)

| HW-044 | Arduino Uno | |--------|-------------| | VCC | 5V | | GND | GND | | DIN | D11 (MOSI) | | CS | D10 (SS) | | CLK | D13 (SCK) | Supply voltage (VCC): 1

What Exactly is the HW-044?

The HW-044 is a digital touch sensor module based on the TTP223 capacitive touch sensor IC. Unlike a physical push-button that requires mechanical force, the HW-044 detects the change in capacitance when a finger (or conductive object) approaches the pad.

Common Aliases: Keyestudio Touch Sensor, TTP223 Module, Capacitive Touch Switch.