SLVSFT8F February 2023 – December 2023 TPS7H1111-SEP , TPS7H1111-SP
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
When the enable pin is low, the device will enter shutdown mode and not regulate the output voltage. Normally, an external resistor divider from VIN to GND is used to feed EN. The resistors can be appropriately sized in order to turn on the device when a desired preset input voltage is reached as shown in Equation 3.
Similarly, a VIN(falling) voltage can also be calculated using Equation 4. The VIN(rising) and VIN(falling) can be thought of as configurable UVLO (undervoltage-lockout) thresholds.
While the TPS7H1111 will turn-on at a VEN of 0.6 V (typ), it is recommended that the final value of VEN is above 0.8 V. This is to ensure appropriate margin above the enable threshold during normal operation to prevent SEFIs during exposure to heavy ions. This recommendation is achieved by satisfying Equation 5.
Alternatively, the EN pin may be driven directly from a microcontroller or FPGA. The low voltage threshold of the enable pin aids in support of 1.1-, 1.8-, 2.5-, and 3.3 V logic levels. Similarly it is recommended the final value of VEN is above 0.8 V (this is typically easily achieved with standard logic levels).