When the cathode/output voltage or current of TLVH431 is not being fed back to the reference/input pin in any form, this device is operating in open loop. With proper cathode current (I_ka) applied to this device, TLVH431 has the characteristics shown in GUID-205FC173-8D8B-4ABC-B7D7-7A8E2D0DA261.html#SLVS5556023. With such high gain in this configuration, the TLVH431 device is typically used as a comparator. With the reference integrated makes TLVH431 the preferred choice when users are trying to monitor a certain level of a single signal.