SLVSGX6B February 2023 – December 2023 TPS7H3302-SEP , TPS7H3302-SP
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
VTT current can flow in both source and sink directions. As the TPS7H3302 is a linear regulator, power is dissipated internal to the device. When the device is sourcing current, the voltage difference between VLDOIN and VTT times IO (IIO ) current becomes the power dissipation as shown in Equation 2.
In this case, if VLDOIN is connected to an alternative power supply lower than the VDDQ voltage, overall power loss can be reduced. For the sink phase, VTT voltage is applied across the internal LDO regulator and the power dissipation (PDISS_SNK) can be calculated by Equation 3.
Because the device does not sink and source current at the same time and the IO current may vary rapidly with time, the actual power dissipation should be the time average of the above dissipations over the thermal relaxation duration of the system. Another source of power consumption is the current used for the internal current control circuitry from the VDD supply and the VLDOIN supply. This can be estimated as 5 mW or less during normal operating conditions. This power must be effectively dissipated from the package.
The thermal performance of an LDO depends on the printed circuit board (PCB) layout.
To further improve the thermal performance of this device, using a larger than recommended thermal land as well as increasing the number of vias helps lower the thermal resistance from junction to heat slug.