US 6,982,601 B2
High isolation/high speed buffer amplifier
Andreas Sibrai, Krottendorf (Austria)
Assigned to Dialog Semiconductor GmbH, Kirchheim/Teck-Nabern (Germany)
Filed on Oct. 20, 2004, as Appl. No. 10/969,519.
Application 10/969519 is a continuation of application No. 10/304785, filed on Nov. 26, 2002, granted, now 6,819,182.
Claims priority of application No. 02392018 (EP), filed on Nov. 07, 2002.
Prior Publication US 2005/0052240 A1, Mar. 10, 2005
This patent is subject to a terminal disclaimer.
Int. Cl. H03F 3/04 (2006.01)
U.S. Cl. 330—288 9 Claims
OG exemplary drawing
 
1. A method to achieve a high isolation and high-speed buffer amplifier comprises:
provide a means to split and to amplify the input signals in several parallel signal paths, a means to mirror the amplified signal to reduce the output load required and to increase the reverse isolation, a means to stabilize the operation, and a capacitor and an additional capacitor parallel to a resistor being hooked up to the node where several signal paths are combined, wherein said capacitors and said resistor are being used to set a frequency dependent gain and to define a frequency bandwidth;
set a frequency dependent gain;
set a frequency bandwidth;
split an input signal in several paths;
amplify the split signal in each signal path in several stages using source follower transistors;
combine again the split and amplified signals; and
mirror the amplified output current applying a multiplication factor.