摘要 |
There is described a driver circuit for a single wire protocol slave unit, the driver circuit comprising (a) at least one current mirror comprising a first transistor (MP1, MN3) and a second transistor (MP2, MN4), wherein the gate of both transistors is connected to a bias node (PBIAS, S2BIAS), and wherein the second transistor is adapted to conduct a mirror current (I2, IOUT) equal to a current (I1, I2) conducted by the first transistor multiplied by a predetermined factor, (b) a bias transistor (MP3, MN5) for selectively connecting and disconnecting the bias node to and from a predetermined potential (VDD, GND) in response to a control signal (ABUF, AN), and (c) a current boosting element for providing a boost current (I1P, I2P) to the bias node for a predetermined period of time when the control signal causes the bias transistor to disconnect the bias node from the predetermined potential. There is also described a universal integrated circuit card device comprising a driver circuit. |
主权项 |
1. A driver circuit for a single wire protocol slave unit, the driver circuit comprising:
at least one current mirror comprising a first transistor and a second transistor, wherein the gate of both transistors is connected to a bias node, and wherein the second transistor is adapted to conduct a mirror current equal to a current conducted by the first transistor multiplied by a predetermined factor, a bias transistor for selectively connecting and disconnecting the bias node to and from a predetermined potential in response to a control signal, and a current boosting element for providing a boost current to the bias node for a predetermined period of time when the control signal causes the bias transistor to disconnect the bias node from the predetermined potential. |