Datasheet

-In
R
fb
+
-
Inverting
R
IN
C
IN
R
fb
R
fb
+
-
Differential
Input
-In
+In
C
IN
R
IN
R
IN
C
IN
R
IN
C
IN
+In
R
fb
Rx
+
-
Cx
Non
Inverting
DRV602
www.ti.com SLOS572D –DECEMBER 2008–REVISED OCTOBER 2010
Charge Pump Flying Capacitor and PVSS Capacitor
The charge pump flying capacitor, C
PUMP
, serves to transfer charge during the generation of the negative supply
voltage. The PVSS capacitor must be at least equal to the charge pump capacitor in order to allow maximum
charge transfer. Low ESR capacitors are an ideal selection, and a value of 1µF is typical. Capacitor values that
are smaller than 1µF can be used, but the maximum output voltage may be reduced and the device may not
operate to specifications.
Decoupling Capacitors
The DRV602 is a DirectPath Line Driver amplifier that require adequate power supply decoupling to ensure that
the noise and total harmonic distortion (THD) are low. A good low equivalent-series-resistance (ESR) ceramic
capacitor, typically 1µF, placed as close as possible to the device PV
DD
lead works best. Placing this decoupling
capacitor close to the DRV602 is important for the performance of the amplifier. For filtering lower frequency
noise signals, a 10-µF or greater capacitor placed near the audio power amplifier would also help, but it is not
required in most applications because of the high PSRR of this device.
Gain setting resistors ranges
The gain setting resistors, R
IN
and R
fb
, must be chosen so that noise, stability and input capacitor size of the
DRV602 is kept within acceptable limits. Voltage gain is defined as R
fb
divided by R
IN
.
Selecting values that are too low demands a large input ac-coupling capacitor, C
IN
. Selecting values that are too
high increases the noise of the amplifier. Table 1 lists the recommended resistor values for different gain
settings.
Table 1. Recommended Resistor Values
INPUT RESISTOR FEEDBACK RESISTOR DIFFERENTIAL INPUT INVERTING INPUT GAIN NON INVERTING INPUT
VALUE, R
IN
VALUE, R
fb
GAIN GAIN
22 kΩ 22 kΩ 1.0 V/V –1.0 V/V 2.0 V/V
15 kΩ 30 kΩ 1.5 V/V –1.5 V/V 2.5 V/V
33 kΩ 68 kΩ 2.1 V/V –2.1 V/V 3.1 V/V
10 kΩ 100 kΩ 10.0 V/V –10.0 V/V 11.0 V/V
Figure 6. Differential Input Figure 7. Inverting
Figure 8. Non-Inverting
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Product Folder Link(s): DRV602