Charge pump circuits for clock and data recovery

A clock data recover (CDR) device configured to generate a clock signal based on an input data stream, the device comprising:

• a data sampler for sampling the input data stream;
• a phase detector configured to generate an early signal and a late signal based on the input data stream;
• a charge pump comprising a first switch and a second switch and a third switch, the first switch being coupled to a first differential voltage based on the late signal, the second switch being coupled to a second differential voltage based on the early signal, the charge pump being configured to generate an offset signal for adjusting the clock signal using a charge pump current based on the first differential voltage and the second differential voltage, the third switch being configured to provide equalization between the first switch and the second switch;
• a loop filter;
• and
• a voltage-controlled oscillator (VCO).

A charge pump circuit device comprising:

• a first transistor configured to generate a first differential voltage based on an input signal, the first transistor comprising a first gate terminal and a first output terminal;
• a first resistor and a second resistor coupled to a first output terminal;
• an operational amplifier comprising a first input terminal and a second output terminal, the second output terminal being coupled to the first output terminal;
• a first switch coupled to the first output terminal, the first switch being turned on by a late signal;
• a second transistor comprising a second gate terminal and a third output terminal, the second gate terminal being coupled to the second output terminal;
• a third resistor coupled to the third output terminal;
• a second switch coupled to the third output terminal, the second switch being turned on by an early signal;
• and
• a fourth resistor coupled to the first switch and the second switch, the fourth resistor being associated with a charge pump current, the charge pump current being at a high voltage when the first switch is on.