For example, the circuit in Figure 1 has a package

power dissipation of 196mW:

where:

ponent of the output voltage.

ponent of the output current.

Therefore:

θ

= 196mW

Adding a coupling capacitor improves the package

power dissipation because there is no DC current to

the load, as shown in Figure 2:

Therefore:

θ

= 15.6mW

If the configuration in Figure 1 were used with all four of

the MAX4234 amplifiers, the absolute maximum power-

dissipation rating of this package would be exceeded

(see the Absolute Maximum Ratings section).

60mW Single-Supply Stereo

Headphone Driver

Two MAX4230/MAX4231s can be used as a single-sup-

ply, stereo headphone driver. The circuit shown in

Figure 2 can deliver 60mW per channel with 1% distor-

tion from a single 5V supply.

a highpass filter that removes the DC bias from the

incoming signal. The -3dB point of the highpass filter is

given by:

f

RC

dB

IN IN

−

=

3

1

2

π

V

I

+

I

2

RMS

RMS

PEAK

≅

==

≅=

+

=

.

.

./

.

V

V

V

IA

V

mA

PEAK

RMS

DC

RMS

2

10

2

0 707

0

10

32

2

22 1

Ω

RMS

DD

DC

RMS

PEAK

V

V

I

+

I

2

≅−

=−

+

=

≅=

+

=

.

.

.

.

.

./

.

V

VV

V

V

I

VV

mA

PEAK

RMS

DC

RMS

2

36

18

10

2

2 507

18

32

10

32

2

78 4

Ω

Ω

High-Output-Drive, 10MHz, 10V/µs,

Rail-to-Rail I/O Op Amps with Shutdown in SC70

_______________________________________________________________________________________

9

RIGHT

AUDIO INPUT

LEFT

AUDIO INPUT

HEADPHONE JACK

TO 32

Ω STEREO

HEADSET

MAX4230

Figure 2. Circuit Example: Adding a Coupling Capacitor

Greatly Reduces Power Dissipation of its Package

3.6V

R

C

32

Ω

R

MAX4230

MAX4231

Figure 1. MAX4230/MAX4231 Used in Single-Supply Operation

Circuit Example