1. General Information

️· Device: Cirrus Logic CS4350 DAC.
️· Purpose of Section: This section details the characteristics of the analog output stage. This is where the digital data is converted into a usable analog signal (voltage).
️· Figures 1 & 2: These figures illustrate the recommended load conditions for the DAC's analog output. Figure 1 suggests an equivalent resistance load (R_L). Figure 2 indicates maximum loading limits.
️· Temperature Dependence: The DAC's performance is affected by temperature. Datasheet presents characteristics at -40°C, 25°C, and 85°C.
️· PDF Dither: One-half LSB (Least Significant Bit) of triangular PDF (Pulse Density Function) dither is applied. This is a technique to reduce quantization noise.
️· Full Scale Output Voltage: The maximum output voltage is dependent on the supply voltage (VA).

2. Electrical Characteristics (VA = 4.75-5.25V) - Standard Operation

️· Full Scale Output Voltage: 2.55 to 3.03 Vpp (peak-to-peak)
️· Quiescent Voltage: 0.5 * VA (where VA is the supply voltage)
️· Maximum DC Current Draw (AOUT pin): 10 μA
️· Maximum Current Draw (VQ pin): 100 μA
️· Output Impedance: 100 Ω
️· Maximum AC Load Resistance (RL): 3 kΩ
️· Maximum Load Capacitance (CL): 100 pF
️· THD+N: Performance data is provided at -40°C, 25°C, and 85°C, with an input signal of 997Hz.
- The THD+N values are provided in Figure 3. Performance degrades with lower VA and higher temperatures.

3. Electrical Characteristics (VA = 3.14-3.46V) - Low Voltage Operation

️· Full Scale Output Voltage: 2.55 to 3.03 Vpp
️· Quiescent Voltage: 0.5 * VA
️· Maximum DC Current Draw (AOUT pin): 10 μA
️· Maximum Current Draw (VQ pin): 100 μA
️· Output Impedance: 100 Ω
️· Maximum AC Load Resistance (RL): 3 kΩ
️· Maximum Load Capacitance (CL): 100 pF
️· THD+N: Performance data is provided at -40°C, 25°C, and 85°C, with an input signal of 997Hz.
- The THD+N values are provided in Figure 5. Performance degrades with lower VA and higher temperatures.

4. Key Graphs & Their Meaning

️· Figure 5 (THD+N vs Output Amplitude for VA = 3.14V): This graph illustrates that THD+N (Total Harmonic Distortion + Noise) increases as the output signal amplitude decreases. It also shows that THD+N generally increases with increasing temperature. The data points for -40°C, 25°C, and 85°C show this trend.
️· General Meaning: The data provided in these graphs emphasizes the sensitivity of the DAC's analog output to supply voltage, temperature, and signal amplitude. Careful design and component selection are crucial to maintain acceptable audio quality.