lm48557tlx National Semiconductor Corporation, lm48557tlx Datasheet - Page 17

• Manufacturer Part Number: lm48557tlx
• Description: Mono, Bridge-tied Load, Ceramic Speaker Driver With I2c Volume Control And Reset
• Manufacturer: National Semiconductor Corporation

PCB Layout Guidelines
Minimize trace impedance of the power, ground and all output
traces for optimum performance. Voltage loss due to trace
resistance between the LM48557 and the load results in de-
creased output power and efficiency. Trace resistance be-
tween the power supply and ground has the same effect as a
poorly regulated supply, increased ripple and reduced peak
output power. Use wide traces for power supply inputs and
amplifier outputs to minimize losses due to trace resistance,
as well as route heat away from the device. Proper grounding
LM48557TL Demoboard Bill of Materials
C1, C2, C5, C6, C7
JU1, JU2, JU3, JU4,
VCM, VDD, GND,
I
OUT+, OUT-
JU1_SH, JU2_SH,
JU3_SH, JU5_SH
2
CV
DD
Designator
, IN+, IN-,
C3, C4
R1, R2
JU5
U1
C8
R3
J2
Quantity
12
1
5
2
1
1
1
2
1
4
LM48557TL Differential, Mono, Ceramic Speaker Driver with I
CAP CERAMIC 2.2µF 10V X5R 10% 0603
CAP .1µF 16V CERAMIC X7R 10% 1206
CAP TANT LOESR 10µF 16V 10% SMD
CONN SOCKET PCB VERT 16POS .1"
CONN HEADER VERT .100 2POS 30Au
CONN HEADER VERT .100 3POS 30Au
RES 5.1K OHM 1/10W 5% 0603 SMD
RES 20K OHM 1/10W 5% 0603 SMD
Jumper Shunt w/handle, 30uin gold plated, 0.100" pitch
17
improves audio performance, minimizes crosstalk between
channels and prevents switching noise from interfering with
the audio signal. Use of power and ground planes is recom-
mended.
Place all digital components and route digital signal traces as
far as possible from analog components and traces. Do not
run digital and analog traces in parallel on the same PCB lay-
er. If digital and analog signal lines must cross either over or
under each other, ensure that they cross in a perpendicular
fashion.
Description
2
C Volume Control, and Reset
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