SNOSB30Q October 2008 – March 2026 LMH6554
PRODUCTION DATA
The LMH6554 is equipped with an enable pin (VEN) to reduce power consumption when not in use. The VEN pin, when not driven, floats high (on). When the VEN pin is pulled low, the amplifier is disabled and the amplifier output stage goes into a high impedance state so the feedback and gain set resistors determine the output impedance of the circuit. For this reason input to output isolation is poor in the disabled state and the part is not recommended in multiplexed applications where outputs are all tied together.
With a 5V difference between V+ and V-, the VEN threshold is ½ way between the supplies (for example 2.5V with 5V single supply) as shown in Figure 7-2. R2 maintains active (enable) mode with VEN floating, and R1 provides input current limiting. VEN also has ESD diodes to either supply.
Figure 7-2 Enable Block Diagram