Diptendu Ghosh

8421510, Apr 16, 2013

May 4, 2011

13/100819

Diptendu Ghosh - Dallas TX, US
Rajarshi Mukhopadhyay - Allen TX, US
Reza Sharifi - Plano TX, US

Texas Instruments Incorporated - Dallas TX

H03K 3/017
H03K 5/04
H03K 7/08

327172, 327173

Within hard disk drives (HDDs), for example, a preamplifier or preamp is generally used to perform read and write operations with a magnetic head. Typically, for write operations, the preamplifier generates a current waveform that uses a DC current to polarize magnetic elements within the disk and overshoot components to compensate for frequency dependent attenuation in the interconnect between the head and preamp. Conventional pulse-shaping circuitry used for this application uses high voltage to accomplish this task. Here, however, pulse-shaping circuitry is provided which can generate a similar waveform using lower voltage (i. e. , about 5V) for this application and others.

20110057732, Mar 10, 2011

Sep 10, 2009

12/557369

Stewart S. Taylor - Beaverton OR, US
Diptendu Ghosh - Austin TX, US

H03K 3/03
H04B 1/16

331 46, 455341

Embodiments of the present invention include a low phase noise oscillator circuit using a current-reuse technique to reduce power consumption and improve phase noise, where the oscillator circuit comprises a first VCO coupled to a second VCO, and the outputs of the first and second VCOs are coupled with passive elements, such as capacitors. The overall power consumption of both the first and second VCOs is about the same as a single VCO. Furthermore, the phase noise is lowered by around 3 dB. Thus, the phase noise performance is improved without increasing the power consumption of the oscillator circuit