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TPSi1085 User Guide
Rev 11/29
Technical Notes
Protection features
The TPSi1085 has a number of enhanced protection features, such as galvanic isolation, active input
voltage clamping, transient suppression, thermal shutdown, and short circuit prevention.
Active Input Voltage Clamping
If the incoming voltage exceeds the maximum voltage of 33V the TPSi1085 will clamp off and limit the
voltage to 33V. If the voltage remains above 33V for an excessive time period the TPSi1085 will turn
off the outputs to protect the power MOSFET absorbing the transient power surge.
Galvanic Isolation
The TPSi1085 features galvanic isolation up to 2250V. This insulates high voltages and isolates
unwanted high currents between the power solution and the embedded system by providing isolated
grounds. This enhances the system protection when servicing and installing the equipment. This is a
key advantage since most embedded power solutions only have a common ground.
Transient Suppression
There are two 3000W transient suppressors (transorbs) for a total of 6000W, in front of the active
input voltage clamping circuit. These transorbs clamp and suppress the incoming power to 58V thus
protecting the active input voltage clamping circuitry and power MOSFET.
Thermal Shutdown
In the event that the environmental conditions raise the internal temperature above the extended
operating temperature, the TPSi1085 will automatically shutdown until the internal temperature
returns to a safe temperature.
Short Circuit
If a short circuit condition exists, the system will shutdown for a speciic time-out period until the short-
circuit condition is removed. This prevents the internal temperature from rising to excessive levels
while maintaining system integrity for an indeinite short circuit output condition.