SLAS997B March 2014 – January 2015 TPA6166A2
PRODUCTION DATA.
The ground terminal must be connected to the ground plane as close as possible to the TPA6166A2, to minimize any inductance in the path. Place the decoupling capacitor as close as possible to the supply terminal, minimizing trace length (and thus the inductance) on the decoupling capacitor connection to ground.
Because INL and INR are single-ended inputs, take care to minimize noise on INL and INR with respect to TPA6166A2 ground. This is best achieved by using then same ground plane for the signal source and the TPA6166A2 with a minimum inductance between them.
The accessory-detection algorithm requires trace capacitance to be minimized between TPA6166A2 and the jack. Depending upon headphone impedance, trace resistance between TPA6166A2 and the jack impacts power delivered to load. If trace resistance is much smaller than headphone impedance, power loss is given by Equation 4. Trace resistance should be minimized based on acceptable power loss.
To minimize crosstalk, trace resistance on RING2 (terminal 3) and SLEEVE (terminal 4) should be minimized. This can be achieved by placing TPA6166A2 close to the jack. For cases where trace resistance is not small, crosstalk is given by Equation 5. In such scenarios, best balance can be achieved by increasing trace width of SLEEVE. RING2 has no constraint on maximum capacitance, and its trace width can be maximized to achieve desired crosstalk performance.
When determining the pad size for the WCSP terminals, use nonsolder mask defined (NSMD) land. With this method, the solder mask opening is made larger than the desired land area, and the opening size is defined by the copper pad width. Figure 35 and Table 8 show the appropriate diameters for a WCSP layout.
SOLDER PAD DEFINITION | COPPER PAD | SOLDER MASK(5) OPENING | COPPER THICKNESS | STENCIL(6)(7)
OPENING |
STENCIL THICKNESS |
---|---|---|---|---|---|
Nonsolder mask defined (NSMD) | 230 μm | 310 μm | 1 oz. max. (32 μm) | 275 μm × 275 μm sq. (rounded corners) | 100 μm thick |
D | E |
---|---|
Max. = 2470 µm | Max. = 2470 µm |
Typ. = 2440 µm | Typ. = 2440 µm |
Min. = 2410 µm | Min. = 2410 µm |