Highly integrated television tuner on a single microcircuit

• US 7,746,412 B2
• Filed: 11/14/2008
• Issued: 06/29/2010
• Est. Priority Date: 04/21/1995
• Status: Expired due to Term

• Current Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Original Assignee: Microtune, Inc. (Qualcomm, Inc.)
• Inventors: Rotzoll, Robert Rudolf, Clayton, Kenneth W., Taddiken, Albert H., Birleson, S. Vincent
• Primary Examiner(s): Natnael; Paulos M
• Application Number:
  US12/271,607
• Publication Number:
  US 20090066847A1
• Time in Patent Office: 592 Days
• Field of Search: 348/731, 348/725, 348/726, 348/555, 348/732, 348/552, 348/553, 455/179.1, 455/3.2, 455/315, 375/347
• US Class Current: 348/731
• CPC Class Codes: H03D 7/161 all the frequency changers being connected in cascade
• CPC Class Codes: H03J 1/005 in a loop
• CPC Class Codes: H03J 2200/14 Tunable filter in receiver contributing to image rejection
• CPC Class Codes: H03J 7/065 the counter or frequency divider being used in a phase locked loop
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/4263 involving specific tuning arrangements, e.g. two tuners
• CPC Class Codes: H04N 5/4446 IF amplifier circuits specially adapted for B&W TV RF amplifiers in general H03F3/189
• CPC Class Codes: H04N 5/455 Demodulation-circuits
• CPC Class Codes: H04N 5/50 Tuning indicators; Automatic tuning control
• CPC Class Codes: H04N 5/52 Automatic gain control
• CPC Class Codes: H04N 5/60 for the sound signals

Abstract

A broadband integrated receiver for receiving input signals and outputting composite video and audio signals is disclosed. The receiver employs an up-conversion mixer and a down-conversion mixer in series to produce an intermediate signal. An intermediate filter between the mixers performs coarse channel selection. The down-conversion mixer may be an image rejection mixer to provide additional filtering.

Claims

1. A television receiver comprising:

a receiver input for receiving an RF signal;

a first mixer having a first input coupled to said receiver and a second input coupled to a first local oscillator, said first local oscillator is controlled digitally to generate a first reference signal; and

a second mixer having a first input coupled to an output of said first mixer and a second input coupled to a second local oscillator, said second local oscillator generating a second reference signal, wherein said second mixer comprises;

a phase splitter having an input coupled to said second local oscillator;

a first and a second multiplier, wherein each multiplier has a first input coupled to an output of said phase splitter and a second input coupled to the output of said first mixer; and

a summer to combine the output of each multiplier.