EL4390 datasheet(7/12 Pages) INTERSIL

7 / 12 page

Typical Performance Curves (Continued)

Applications Information

Circuit Operation

Each channel of the EL4390 contains a current feedback

amplifier and a TTL/CMOS compatible clamp circuit. The

current that the clamp can source or sink into the non-

inverting input is approximately:

I = (VCLAMP - VIN+) / 120

So, when the non-inverting input is at the same voltage as

the clamp reference, no current will flow, and hence no

charge is added to the capacitor. When there is a difference

in voltage, current will flow, in an attempt to cancel the error

AT THE NON-INVERTING input. The amplifier’s offset

voltage and (IB- × RF) DC errors are not cancelled with this

loop. It is purely a method of adding a controlled DC offset to

the signal.

As well as the offset voltage error, which goes up with gain,

and the IB- × RF error which drops with gain, there is also the

IB+ error term. Since the amplifier is capacitively coupled,

this small current is slowly integrated and shows up as a

very slow ramp voltage. Table below shows the output

Maximum Power Dissipation

vs Ambient Temperature—

16-Pin PDIP

Maximum Power Dissipation

vs Ambient Temperature—

16-Pin PDIP

Simplified Schematic of One Channel of EL4390

EL4390

EL4390 Scheda tecnica(PDF) 7 Page - Intersil Corporation