Datasheet

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BYPASSING THE BOOST CONVERTER
Toko
1098AS-4R7M
ToshibaCRS06
SchottkyDiode
V
DD
SW
IN–
IN+
AGND
PGND
VOUT+
VOUT–
V OUT
CC
V IN
CC
22 Fm
22 Fm
1 Fm
ToBattery
Left
Channel
Input
C
IN
C
IN
V FB
CC
SDb
SDd
GAIN
4.7 Hm
GND=Bypass
V =BoostMode
DD
1 Fm
R1
50kΩ
R2
500kΩ
TPA2013D1
GPIO
EFFICIENCY AND THERMAL INFORMATION
JA
1 1
= = = 80.64 C/W
Derating Factor 0.0124
q °
(8)
TPA2013D1
SLOS520 – AUGUST 2007
Bypass the boost converter to drive the Class-D amplifier directly from the battery. Place a Shottky diode
between the SW pin and the V
CC
IN pin. Select a diode that has an average forward current rating of at least 1A,
reverse breakdown voltage of 10 V or greater, and a forward voltage as small as possible. See Figure 34 for an
example of a circuit designed to bypass the boost converter.
Do not configure the circuit to bypass the boost converter if V
DD
is higher than V
CC
when the boost converter is
enabled ( SDb ≥ 1.3 V); V
DD
must be lower than V
CC
for proper operation. V
DD
may be set to any voltage within
the recommended operating range when the boost converter is disabled ( SDb ≤ 0.3V).
Place a logic high on SDb to place the TPA2013D1 in boost mode. Place a logic low on SDb to place the
TPA2013D1 in bypass mode.
Figure 34. Bypass Circuit
The maximum ambient temperature depends on the heat-sinking ability of the PCB system. The derating factors
for the YZH and RGP packages are shown in the dissipation rating table. Apply the same principles to both
packages. Using the YZH package, and converting this to θ
JA
:
Given θ
JA
of 80.64 ° C/W, the maximum allowable junction temperature of 150 ° C, and the maximum internal
dissipation of 0.317 W (V
DD
= 3.6 V, P
O
= 1.7 W), the maximum ambient temperature is calculated with the
following equation:
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Product Folder Link(s): TPA2013D1