US 12,289,084 B2
High tolerance variable gain amplifiers
Masahiro Yoshioka, Allen, TX (US); Gabriel Hernandez De La Cruz, Richardson, TX (US); and Lawrence Cotton, Allen, TX (US)
Assigned to Texas Instruments Incorporated, Dallas, TX (US)
Filed by TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US)
Filed on Jan. 31, 2022, as Appl. No. 17/588,662.
Prior Publication US 2023/0246612 A1, Aug. 3, 2023
Int. Cl. H03F 3/45 (2006.01); H03F 1/30 (2006.01)
CPC H03F 3/45183 (2013.01) [H03F 1/301 (2013.01)] 15 Claims
OG exemplary drawing
 
1. An amplifier comprising:
a first operational transconductance amplification (OTA) circuit including a reference signal input section configured to receive a reference voltage to generate an output current based on the reference voltage and a transconductance value of the first OTA circuit, the first OTA circuit further configured to generate a comparison current;
a second OTA circuit coupled to the first OTA circuit, the second OTA circuit including an input signal input section configured to receive an input voltage and an output at which an output signal is output, the second OTA circuit having substantially the same transconductance value as the first OTA circuit; and
amplifying circuitry comprising:
an input;
an output; and
a resistor having a first terminal and a second terminal;
wherein the input is coupled to the output of the second OTA, and the first terminal of the resistor is coupled to the input and the second terminal of the resistor is coupled to the output.