2.1-channel application using one device

AN4569

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DocID026803 Rev 1

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2.1-channel application using one device

2.1

Schematic

Figure 1. 2.1-channel application with one device

In this configuration only one device has been used. The CONFIG pin must be connected to

GND.

2.1.1

Component selection

The selection of components is a key factor for the cost of the entire application.

The following list includes components grouped according to different sections of the

schematic:

-Decoupling capacitors on VDD_DIG and PLL_VDD pins are 100 nF low voltage;

-Decoupling capacitors on VCC pins (100 nF, 1 uF and 100 uF) must be aligned with the

external power supply used. If 24 V is used, the rate for the capacitors must be 35 V;

-Decoupling capacitors on the internal regulator (C6 and C7 in the schematic) can have a

low voltage rate. This because they are 3.3 V regulators;

-Coil saturation current is compatible with the peak current of the application;

-The size of the resistor divider (R5, R6, R7 and R8) must be selected according to the VCC

selected;

-The rate for the capacitors divider (C19, C20, C21 and C22) must be selected according to

the VCC selected;

-The size of the resistor and capacitor dividers must be selected according to the output

load and desired curve response. In Section 2.1.7: DC cut, there is a detailed explanation.