Application Information

TS4985

18/29

4

Application Information

The TS4985 integrates two monolithic power amplifiers with a BTL (Bridge Tied Load) output

type (explained in more detail in

Section 4.1). For this discussion, only the left-channel amplifier

will be referred to.

Referring to the schematic in

Figure 61, we assign the following variables and values:

4.1

BTL configuration principle

BTL (Bridge Tied Load) means that each end of the load is connected to two single-ended

output amplifiers. Thus, we have:

Single-ended output 1 =

Single-ended output 2 =

The output power is:

For the same power supply voltage, the output power in a BTL configuration is four times higher

than the output power in a single-ended configuration.

Figure 61. Typical application schematic - left channel

Rin = Rin-L

Cin = Cin-L

Input L

GND

Rfeed = Rfeed-L

VCC

Cs

1u

RL

Cfeed = Cfeed-L

Cb

1u

AV = -1

Vin-

Vin+

Vout 1

Vout 2

+

-

+

-

VO-L

VO+L

IN-L

IN+L

=

=

=

=

Bias

Bypass

TS4985

P

out

2V

outRMS

()

2

R

L

------------------------------------

=