发明名称 |
Low swing voltage mode driver |
摘要 |
An output driver includes control logic configured to switch on a pull-up circuit and a pull-down circuit to provide an output impedance for a logic low on a transmission line. The output driver includes a variable pull-up resistor. The control logic is configured to switch on the pull-up circuit to a first value of impedance to drive a logic high on the transmission line. The control logic is configured to switch on the pull-up circuit to a second value of impedance and to switch on the pull-down circuit to provide the output impedance to drive a logic low on the transmission line. The system could alternatively be configured for the inverse to switch on a combination of pull-up and pull-down circuits for a logic high, where the pull-down circuit is switched on for a logic low. |
申请公布号 |
US9152257(B2) |
申请公布日期 |
2015.10.06 |
申请号 |
US201213730642 |
申请日期 |
2012.12.28 |
申请人 |
Intel Corporation |
发明人 |
McCall James A.;Bains Kuljit S.;Conrow Derek M.;Martin Aaron |
分类号 |
H03K3/012;G06F3/041;H03K19/00;H03K19/0175 |
主分类号 |
H03K3/012 |
代理机构 |
Blakely, Sokoloff, Taylor & Zafman LLP |
代理人 |
Blakely, Sokoloff, Taylor & Zafman LLP |
主权项 |
1. An output driver comprising:
a pull-up circuit including a variable pull-up resistor to pull up a transmission line driven by the output driver; a pull-down circuit including a pull-down resistor to pull down the transmission line; and driver control logic coupled to the pull-up circuit and the pull-down circuit, the driver control logic to establish a first value of impedance of the pull-up circuit to drive a logic high on the transmission line, the driver control logic to establish a second value of impedance of the pull-up circuit and to switch on the pull-down circuit to drive a logic low on the transmission line, where the second value of impedance of the pull-up circuit in parallel with an impedance of the pull-down circuit provides an effective output impedance for the output driver when driving the logic low; and, reference voltage logic to adjust a center reference voltage (Vref) to reduce a voltage swing on the transmission line. |
地址 |
Santa Clara CA US |