SLLSEL2C September 2015 – July 2016 SN65DP149 , SN75DP149
PRODUCTION DATA.
TI recommends to use at a minimum a four layer stack up to accomplish a low-EMI PCB design. TI recommends six layers because the SNx5DP149 is a two voltage rail device.
On a high-K board: TI recommends to solder the PowerPAD™ onto the thermal land. A thermal land is the area of solder-tinned-copper underneath the PowerPAD package. On a high-K board, the SNx5DP149 device can operate over the full temperature range by soldering the PowerPAD onto the thermal land without vias.
On a low-K board: For the device to operate across the temperature range on a low-K board, a 1-oz Cu trace connecting the GND pins to the thermal land must be used. A simulation shows RθJA = 100.84°C/W allowing 545-mW power dissipation at 70°C ambient temperature.
A general PCB design guide for PowerPAD packages is provided in PowerPAD Thermally Enhanced Package, SLMA002.