ZHCS891G April 2012 – December 2017 TPA3116D2 , TPA3118D2 , TPA3130D2
PRODUCTION DATA.
- 1 特性
- 2 應(yīng)用
- 3 說明
- 4 修訂歷史記錄
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 Gain Setting and Master and Slave
- 7.3.2 Input Impedance
- 7.3.3 Startup and Shutdown Operation
- 7.3.4 PLIMIT Operation
- 7.3.5 GVDD Supply
- 7.3.6 BSPx AND BSNx Capacitors
- 7.3.7 Differential Inputs
- 7.3.8 Device Protection System
- 7.3.9 DC Detect Protection
- 7.3.10 Short-Circuit Protection and Automatic Recovery Feature
- 7.3.11 Thermal Protection
- 7.3.12 Device Modulation Scheme
- 7.3.13 Efficiency: LC Filter Required with the Traditional Class-D Modulation Scheme
- 7.3.14 Ferrite Bead Filter Considerations
- 7.3.15 When to Use an Output Filter for EMI Suppression
- 7.3.16 AM Avoidance EMI Reduction
- 7.4 Device Functional Modes
- 8 Application and Implementation
- 9 Power Supply Recommendations
- 10Layout
- 11器件和文檔支持
- 12機械、封裝和可訂購信息
封裝選項
機械數(shù)據(jù) (封裝 | 引腳)
- DAP|32
散熱焊盤機械數(shù)據(jù) (封裝 | 引腳)
- DAP|32
訂購信息
7.3.2 Input Impedance
The TPA31xxD2 family input stage is a fully differential input stage and the input impedance changes with the gain setting from 9 kΩ at 36 dB gain to 60 kΩ at 20 dB gain. Table 1 lists the values from min to max gain. The tolerance of the input resistor value is ±20% so the minimum value will be higher than 7.2 kΩ. The inputs need to be AC-coupled to minimize the output dc-offset and ensure correct ramping of the output voltages during power-ON and power-OFF. The input ac-coupling capacitor together with the input impedance forms a high-pass filter with the following cut-off frequency:
If a flat bass response is required down to 20 Hz the recommended cut-off frequency is a tenth of that, 2 Hz. Table 2 lists the recommended ac-couplings capacitors for each gain step. If a -3 dB is accepted at 20 Hz 10 times lower capacitors can used – for example, a 1 µF can be used.
Table 2. Recommended Input AC-Coupling Capacitors
| GAIN | INPUT IMPEDANCE | INPUT CAPACITANCE | HIGH-PASS FILTER |
|---|---|---|---|
| 20 dB | 60 kΩ | 1.5 µF | 1.8 Hz |
| 26 dB | 30 kΩ | 3.3 µF | 1.6 Hz |
| 32 dB | 15 kΩ | 5.6 µF | 1.9 Hz |
| 36 dB | 9 kΩ | 10 µF | 1.8 Hz |
Figure 28. Input ImpedanceThe input capacitors used should be a type with low leakage, like quality electrolytic, tantalum or ceramic. If a polarized type is used the positive connection should face the input pins which are biased to 3 Vdc.