Bootstrapped line-protector cmos switch
AssigneeAnalog Devices International Unlimited Company
InventorsSharad Vijaykumar, Patrick C. Kirby
Life of this patent
Estimating the term…
Abstract
A line protector circuit comprises an external side switch circuit coupled to an external circuit node of the line protector circuit, an internal side switch circuit coupled in series to the external side switch circuit and an internal circuit node of the line protector circuit, a high supply circuit node and a low supply circuit node, and switch control circuitry configured to deactivate the internal side switch circuit and divert a bias current from the external side switch to the low supply circuit node when the external voltage exceeds a high supply voltage of the high supply circuit node.
Claims20
A line protector circuit comprising:
- an external side switch circuit coupled to an external circuit node of the line protector circuit;
- an internal side switch circuit coupled in series to the external side switch circuit and an internal circuit node of the line protector circuit;
- a high supply circuit node and a low supply circuit node;
- and
- switch control circuitry configured to deactivate the internal side switch circuit and divert a bias current from the external side switch to the low supply circuit node when the external voltage exceeds a high supply voltage of the high supply circuit node.
A method of operating a line protector circuit, the method comprising:
- monitoring an external voltage connected to an external side switch circuit of the line protector circuit, wherein the line protector circuit includes the external switch circuit connected in series with an internal side switch circuit and the internal side switch circuit is connected to internal circuitry;
- and
- deactivating the internal side switch circuit and diverting a bias current from the external side switch to a low supply circuit node when the external voltage exceeds a high supply voltage of the line protector circuit.
An electronic system comprising:
- a line protector circuit including:
- an analog switch circuit coupled to an external circuit node of the line protector circuit and an internal circuit node of the line protector circuit;
- a high supply circuit node and a low supply circuit node;
- switch control circuitry configured to deactivate the internal circuit node connection of the analog switch and divert a bias current from the external circuit node to the low supply circuit node when the external voltage exceeds a high supply voltage of the high supply circuit node;
- a bypass switch circuit connected to the internal circuit node;
- and
- bypass switch logic circuitry configured to maintain a connection to the internal circuit node when the external voltage exceeds the high supply voltage.
Dependencies are inferred from the claim text.