SA58635 NXP Semiconductors, SA58635 Datasheet - Page 23

• Manufacturer Part Number: SA58635
• Manufacturer: NXP Semiconductors

NXP Semiconductors
SA58635_1
Product data sheet
13.3 PCB layout considerations
13.4 Thermal information
For a required 3 dB cut-off frequency,
For C
4 dB, the SA58635 input resistance, R
C
Component location is very important for performance of the SA58635. Place all external
components very close to the device. Placing decoupling capacitors directly at the power
supply pins increases efficiency because the resistance and inductance in the trace
between the device power supply pins and the decoupling capacitor causes a loss in
power efficiency.
The trace width and routing are also very important for power output and noise
considerations.
For the input pins (INLP, INLN, INRP, INRN), the traces must be symmetrical and run
side-by-side to maximize common-mode cancellation.
The SA58635 16-bump WLCSP package ground bumps are soldered directly to the PCB
heat spreader. The heat spreader is the PCB ground plane or special heat sinking layer
designed into the PCB. The thickness and area of the heat spreader may be maximized to
optimize heat transfer and achieve lower package thermal resistance.
C
i
i
in
=
Equation 1
i
----------------------------------- -
2π
= 1 μF, the 3 dB cut-off frequency will vary with gain settings. For gain setting of
×
R
1
i
×
f
–
yields f
3dB
Rev. 01 — 26 March 2010
−3dB
= 14.4 Hz.
Equation 2
i
is 11.06 kΩ (refer to
2 × 25 mW class-G stereo headphone driver
is used to determine C
Table
14). Substituting R
SA58635
© NXP B.V. 2010. All rights reserved.
i
:
23 of 30
i
and
(2)