TPA2001D2
1-W FILTERLESS STEREO CLASS-D AUDIO POWER AMPLIFIER
SLOS292A – MARCH 2000 – REVISED APRIL 2000
APPLICATION INFORMATION
differential input
The differential input stage of the amplifier cancels any noise that appears on both input lines of a channel. To
use the TPA2001D2 EVM with a differential source, connect the positive lead of the audio source to the RINP
(LINP) input and the negative lead from the audio source to the RINN (LINN) input. To use the TPA2001D2 with
a single-ended source, ac ground the RINN and LINN inputs through a capacitor and apply the audio single to
the RINP and LINP inputs. In a single-ended input application, the RINN and LINN inputs should be ac grounded
at the audio source instead of at the device inputs for best noise performance.
shutdown modes
The TPA2001D2 employs a shutdown mode of operation designed to reduce supply current, I
DD
, to the absolute
minimum level during periods of nonuse for battery-power conservation. The SHUTDOWN input terminal
should be held high during normal operation when the amplifier is in use. Pulling SHUTDOWN low causes the
outputs to mute and the amplifier to enter a low-current state, I
DD(SD)
= 1
µA.
SHUTDOWN should never be left
unconnected because amplifier operation would be unpredictable.
using low-ESR capacitors
Low-ESR capacitors are recommended throughout this application section. A real (as opposed to ideal)
capacitor can be modeled simply as a resistor in series with an ideal capacitor. The voltage drop across this
resistor minimizes the beneficial effects of the capacitor in the circuit. The lower the equivalent value of this
resistance the more the real capacitor behaves like an ideal capacitor.
evaluation circuit
LOUT–
GAIN0
GND
C1
0.1
µF
LIN+
U1
TPA2001D2
PGND
LOUTN
GAIN0
PGND
LOUTP
BYPASS
LPVDD
C21
LINN
AGND
LINP
VDD
ROSC
RINP
RPVDD
GAIN1
ROUTP
PGND
C19
0.1
µF
C8
10 uF
C20
0.1
µF
R2
120k
R4
120 k
GAIN1
0.1
µF
C5
C6
1
µF
10
µF
GND
LOUT+
C2
0.1
µF
LIN–
120 k
R1
C17
0.1
µF
LPVDD
VDD
VDD
0.1
µF
RIN–
C4
RIN+
0.1
µF
GND
R3
120 k
C18
0.1
µF
C3
C7
220 pF
COSC
RINN
RPVDD
SHUTDOWN
ROUTN
PGND
ROUT+
GND
GND
GND
SHUTDOWN
S1
ROUT–
NOTE: R1, R3, and R4 are used in the EVM but are not required for normal applications.
10
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
ETC [ ETC ]
