POWER DISSIPATION

The LMH6572 is optimized for maximum speed and perfor-

mance in the small form factor of the standard SSOP pack-

age. To achieve its high level of performance, the LMH6572

consumes 23 mA of quiescent current, which cannot be

neglected when considering the total package power dissi-

pation limit. To ensure maximum output drive and highest

performance, thermal shutdown is not provided. Therefore, it

is of utmost importance to make sure that the T

exceeded due to the overall power dissipation.

Follow these steps to determine the Maximum power dissi-

pation for the LMH6572:

1.

Calculate the quiescent (no-load) power: P

(V

2.

Calculate the RMS power dissipated in the output stage:

P

I

external load and V

3.

Calculate the total RMS power: P

The maximum power that the LMH6572, package can dissi-

pate at a given temperature can be derived with the following

equation:

P

θ

ture (˚C) and

θ

ambient, for a given package (˚C/W). For the SSOP package

θ

ESD PROTECTION

The LMH6572 is protected against electrostatic discharge

(ESD) on all pins. The LMH6572 will survive 2000V Human

Body model and 200V Machine model events. Under normal

operation the ESD diodes have no effect on circuit perfor-

mance. There are occasions, however, when the ESD di-

odes will be evident. If the LMH6572 is driven by a large

signal while the device is powered down the ESD diodes will

conduct. The current that flows through the ESD diodes will

either exit the chip through the supply pins or will flow

through the device, hence it is possible to power up a chip

with a large signal applied to the input pins. Shorting the

power pins to each other will prevent the chip from being

powered up through the input.

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