Three state switch detection using current sensing
First Claim
Patent Images
1. A circuit for converting a three state input to a two-bit binary output comprising:
- a first switch connecting a first output to said input when said input is high, said first output connected to a first reference voltage; and
a second switch connecting a second output to said input when said input is low, said second output connected to a second reference voltage.
11 Assignments
0 Petitions
Accused Products
Abstract
A three state switch detection circuit converts a three state input to a two-bit binary output readable by a micro-controller or other digital logic. The circuit utilized complementary NPN and PNP transistors having coupled emitters and coupled bases connected by a resistor. The collector of the PNP transistor is connected by a resistor to ground while a complementary resistor ties the collector of the NPN transistor to VBATT. Additional circuitry preferably converts the voltage output from the collectors to a suitable voltage level readable by the micro-controller or other digital logic device.
-
Citations
15 Claims
-
1. A circuit for converting a three state input to a two-bit binary output comprising:
-
a first switch connecting a first output to said input when said input is high, said first output connected to a first reference voltage; and a second switch connecting a second output to said input when said input is low, said second output connected to a second reference voltage. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A circuit for controlling a motor-driven feature in a vehicle comprising:
-
a first motor for operating a motor-driven feature, said first motor having a first input line and a second input line; a user switch for operating said first motor, said user switch having a low state, a high state and an open state; a tri-state detection circuit receiving a tri-state signal from said user switch and converting said tri-state signal into a two-bit binary signal, said two-bit binary signal comprising a first bit and a second bit indicating the state of said user switch, said tri-state detection circuit including a first switch and a second switch, said first switch connecting said first bit to said user switch when said user switch is in said high state, said second switch connecting said second bit to said user switch when said user switch is in said low state; and a controller receiving said two-bit binary signal from said tri-state detection circuit, said controller operating said first motor to a stored setting for said motor-driven feature only when said two-bit binary signal indicates that said user switch is in said open state. - View Dependent Claims (10, 11, 12, 13)
-
-
14. A method for converting a three state input to a two-bit binary output including the steps of:
-
connecting said input to a first output when said input is high; connecting said input to a second output when said input is low; connecting said first output to a first reference voltage when said input is low; connecting said first output to said first reference voltage when said input is open; connecting said second output to a second reference voltage when said output is high; and connecting said second output to said second reference voltage when said output is open. - View Dependent Claims (15)
-
Specification