Datasheet

TPS22980

SLVSB61C –DECEMBER 2011–REVISED SEPTEMBER 2013

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Reverse Current Protection

Reverse current protection for the V3P3 supply to OUT triggers at I

REV3P3

causing the V3P3 supply switch to

open. When the HV_EN signal is not asserted and reverse current protection is triggered, a discharge current

source is turned on to bring the output voltage to 3.3V nominal.

Thermal Shutdown

The device enters thermal shutdown when junction temperature reaches T

. The device will resume the

previous state on power up once the junction temperature has dropped by 10°C. Connect thermal vias to the

exposed GND pad underneath the device package for improved thermal diffusion.

UVLO

When the VHV rail reaches the under-voltage lockout threshold of V

HVUVLO

while HV_EN is high, the device will

switch back to V3P3. Once the UVLO condition has cleared, the device will switch to VHV again. When the V3P3

rail reaches the under-voltage lockout threshold of V

3P3UVLO

, regardless of the states of any digital logic controls,

the device will open all switches and enter a reset condition.

Input Inductive Bounce at Short Circuit

When the TPS22980 is operating at high currents and high input voltage on VHV, a short circuit condition can

cause the input to exceed the maximum safe operating condition for VHV. When a significant inductance is

present at the VHV input, sudden turn off of current through the device may produce a large enough inductive

voltage bounce that exceeds the maximum safe operating condition and may damage the TPS22980. To prevent

this, reduce any inductance at the input. Input capacitors, such as 4.7µF, can reduce the supply bounce and are

recommended.

Single Point Failure Protection

The TPS22980 current limits are set by the RISET resistances. Shorting one of these resistance would result in a

single point failure that removes the current limiter for that particular input and mode. Without current limiting, an

excessive current load may damage the TPS22980 and the system. To prevent a single point failure from

occurring, the RISET resistances can be divided into two series resistances each as shown in Figure 10. Failure

of a single resistance will not result in runaway current and damage.

Figure 10. R

ISET

Division to Prevent Single Point Failure

Product Folder Links :TPS22980