MAX4364ESA/V+T Maxim Integrated Products, MAX4364ESA/V+T Datasheet - Page 10

• Manufacturer Part Number: MAX4364ESA/V+T
• Description: IC AMP AUDIO PWR 1.4W MONO 8SOIC
• Manufacturer: Maxim Integrated Products
• Type: Class ABr

Specifications of MAX4364ESA/V+T

• Output Type: 1-Channel (Mono)
• Max Output Power X Channels @ Load: 1.4W x 1 @ 8 Ohm
• Voltage - Supply: 2.7 V ~ 5.5 V
• Features: Depop, Short-Circuit and Thermal Protection, Shutdown
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The increase in power delivered by the BTL configura-
tion directly results in an increase in internal power dis-
sipation over the single-ended configuration. The
maximum power dissipation for a given V
given by the following equation:
If the power dissipation for a given application exceeds
the maximum allowed for a given package, reduce
V
temperature or add heat sinking to the device. Large
output, supply, and ground PC board traces improve
the maximum power dissipation in the package.
Thermal-overload protection limits total power dissipa-
tion in the MAX4364/MAX4365. When the junction tem-
perature exceeds +160°C, the thermal protection
circuitry disables the amplifier output stage. The ampli-
fiers are enabled once the junction temperature cools
by 15°C. This results in a pulsing output under continu-
ous thermal overload conditions as the device heats
and cools.
The MAX4365 TDFN package features an exposed
thermal pad on its underside. This pad lowers the ther-
mal resistance of the package by providing a direct
heat conduction path from the die to the PC board.
Connect the exposed thermal pad to circuit ground by
using a large pad, ground plane, or multiple vias to the
ground plane.
The efficiency of the MAX4364/MAX4365 is calculated
by taking the ratio of the power delivered to the load to
the power consumed from the power supply. Output
power is calculated by the following equations:
where V
BTL amplifiers, the supply current waveform is a full-
wave rectified sinusoid with the magnitude proportional
to the peak output voltage and load. Calculate the sup-
ply current and power drawn from the power supply by
the following:
1.4W and 1W, Ultra-Small, Audio Power
Amplifiers with Shutdown
10
CC
, increase load impedance, decrease the ambient
______________________________________________________________________________________
PEAK
is half the peak-to-peak output voltage. In
P
DISS MAX
P
I
OUT
CC
(
)
2
V
V
PEAK
PEAK
2
2
R
R
V
L
2
CC
L
R
2
L
2
CC
Efficiency
and load is
The efficiency of the MAX4364/MAX4365 is:
The device efficiency values in Table 1 are calculated
based on the previous equation and do include the
effects of quiescent current. Note that efficiency is low
at low output-power levels, but remains relatively con-
stant at normal operating, output-power levels.
External feedback components set the gain of both
devices. Resistors R
Circuit/Functional Diagram) set the gain of the amplifier
as follows:
Optimum output offset is achieved when R
Vary the gain by changing the value of R
the MAX4364/MAX4365 in a high-gain configuration
(greater than 8V/V), a feedback capacitor may be
required to maintain stability (see Figure 2). C
limit the bandwidth of the device, preventing high-fre-
quency oscillations. Ensure that the pole created by C
and R
The input capacitor (C
a highpass filter that removes the DC bias from an
incoming signal. The AC-coupling capacitor allows the
amplifier to bias the signal to an optimum DC level.
Assuming zero source impedance, the -3dB point of
the highpass filter is given by:
Choose R
section. Choose C
lowest frequency of interest. Setting f
affects the low-frequency response of the amplifier. Use
capacitors whose dielectrics have low-voltage coeffi-
F
is not within the frequency band of interest.
IN
according to the Gain-Setting Resistors
P
IN
P
IN
OUT
P
3
A
IN
F
dB
VD
such that f
and R
IN
V
CC
), in conjunction with R
2
2
Component Selection
2
R C
IN
V
P
2
R
IN IN
R
1
PEAK
OUT L
V
IN
R
F
(see Typical Application
Gain-Setting Resistors
CC
L
2
-3dB
R
is well below the
IN
-3dB
. When using
Input Filter
F
F
too high
= 20k .
IN
and R
forms
F
F