Slew rate controlled ramp and its use in liquid crystal displays

A liquid crystal display, comprising:

• a plurality of pixel elements in an array of pixel rows and pixel columns, wherein each pixel element includes a ramp input line;
• a ramp generator producing a ramp during a ramp period and a return during a fly back period;
• an operational transconductance amplifier (OTA) having a non-inverting input connected to said ramp generator, an inverting input, an output connected to said pixel element ramp input lines and to said inverting input, and a tail current line;
• a first current source for sinking a first current from said tail current line;
• a switch having a first terminal that is connected to said tail current line, a second terminal, and a switch control, wherein said first terminal and said second terminal are electrically shorted together when said switch control is closed;
• and
• a second current source connected to said second terminal, said second current source for sinking a second current from said tail current line when said switch control is closed;
• and
• a control for closing said switch control during said fly back period.

An operational transconductance amplifier circuit, comprising:

• an operational transconductance amplifier (OTA) having an inverting input, a non-inverting input, an output, and a tail current line;
• a load connected to said output;
• a first current source for sinking a first current from said tail current line;
• a switch having a first terminal connected to said tail current line, a second terminal, and a switch control, wherein said first terminal and said second terminal are electrically shorted together when said switch control receives a close signal;
• and
• a second current source connected to said second terminal;
• wherein said second current source is for sinking a second current from said tail current line when said switch control receives said close signal.