lm4838mtx National Semiconductor Corporation, lm4838mtx Datasheet - Page 7

• Manufacturer Part Number: lm4838mtx
• Description: Stereo 2w Audio Power Amplifiers With Dc Volume Control And Selectable Gain
• Manufacturer: National Semiconductor Corporation

Electrical Characteristics for Bridged Mode Operation
Note 16: All bumps have the same thermal resistance and contribute equally when used to lower thermal resistance. The LM4838ITL demo board (views featured
in the Application Information section) is a four layer board with two inner layers. The second inner layer is a V
The planes measure 1,900mils x 1,750mils (48.26mm x 44.45mm) and aid in spreading heat due to power dissipation within the IC.
Note 17: All bumps have the same thermal resistance and contribute equally when used to lower thermal resistance. The LM4838GR Demo Board is a four layer
PC Board with 2 inner layers. The second inner layer and bottom outside layers are both grounded. The planes measure 3200 x 3700 mills and aid in spreading
heat due to power dissipation within the IC.
Typical Application
Truth Table for Logic Inputs
Note 18: If system beep is detected on the Beep In pin, the system beep will be passed through the bridged amplifier regardless of the logic of the Mute and HP
sense pins.
Gain
Sel
X
X
0
0
0
0
1
1
1
1
Mode
X
X
0
0
1
1
0
0
1
1
Headphone
Sense
0
1
0
1
0
1
0
1
X
X
FIGURE 2. Typical Application Circuit ( LQ Package Pinout )
Mute
0
0
0
0
0
0
0
0
1
X
Shutdown Output Stage Set To
(Note 18)
0
0
0
0
0
0
0
0
0
1
External Gain
External Gain
External Gain
External Gain
Internal Gain
Internal Gain
Internal Gain
Internal Gain
Shutdown
7
Muted
DC Volume
Adjustable
Adjustable
Adjustable
Adjustable
DD
Fixed
Fixed
Fixed
Fixed
plane with the bottom outside layer a GND plane.
X
X
(Notes 7, 10) (Continued)
Configuration
Output Stage
20013303
Muted
BTL
BTL
BTL
BTL
SE
SE
SE
SE
X
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