### Overview of DAC8564ICPW The **DAC8564ICPW** is a low-power, voltage-output, four-channel, 16-bit digital-to-analog converter (DAC). It is designed by Texas Instruments and is widely used in industrial process control, instrumentation, and optical networking. --- ### Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Resolution** | 16-Bit | | **Number of Channels** | 4 (Quad) | | **Interface** | SPI (Serial Peripheral Interface) | | **Settling Time** | 10 $\mu$s | | **Internal Reference** | 2.5V (2ppm/°C drift) | | **Supply Voltage (AVDD)** | 2.7V to 5.5V | | **Package** | TSSOP-16 | | **Power Consumption** | 0.7mA at 5V | --- ### Core Electronic Features #### 1. Precision Internal Reference The device includes a built-in 2.5V reference with very low temperature drift. This eliminates the need for an external reference component in many applications, saving board space and cost. #### 2. Monotonicity and Linearity The DAC8564 is guaranteed monotonic over the specified temperature range. It features low **Differential Non-Linearity (DNL)** and **Integral Non-Linearity (INL)**, ensuring high precision in control loops. #### 3. Power-On-Reset (POR) The "ICPW" variant specifically includes a Power-On-Reset circuit that ensures the DAC outputs power up to **zero-scale**. This is critical for safety in industrial applications where a sudden mid-scale or full-scale voltage during boot-up could damage connected hardware. #### 4. SPI Interface It uses a 3-wire serial interface that operates at clock rates up to 50MHz. It is compatible with standard SPI, QSPI, Microwire, and DSP interface standards. --- ### Pin Configuration (TSSOP-16) | Pin | Name | Description | | :--- | :--- | :--- | | 1 | $V_{REF}H$ | Reference voltage input/output | | 2-5 | $V_{OUT}A-D$ | Analog output voltages for Channels A, B, C, and D | | 11 | $SCLK$ | Serial clock input | | 12 | $DIN$ | Serial data input | | 13 | $\overline{SYNC}$ | Level-triggered control input (Active Low) | | 16 | $AV_{DD}$ | Analog power supply | --- ### Example SPI Command Structure To write data to the DAC, a 24-bit shift register is used: * **8 Bits:** Control and Address bits (determines which channel to update). * **16 Bits:** Data bits (the digital value to be converted). ```c // Example pseudo-code for a 16-bit write void write_DAC8564(uint8_t address, uint16_t data) { digitalWrite(SYNC_PIN, LOW); // Select the DAC SPI.transfer(address); // Send control/address (e.g., 0x00 for Channel A) SPI.transfer(data >> 8); // Send high byte SPI.transfer(data & 0xFF); // Send low byte digitalWrite(SYNC_PIN, HIGH); // Load data to DAC registers } ``` ---