Device and method for programming high impedance states upon select input/output pads

An integrated circuit, comprising:

• a high impedance programming unit configured to operatively program a plurality of high impedance states;
• a shift data storage coupled to said high impedance programming unit for storing said plurality of high impedance states;
• and
• a transistor having a source-drain path connected between one of a plurality of input/output pads and a power supply conductor, said transistor having a gate terminal operably connected for receiving a signal representative of one of said plurality of high impedance states and for conveying a respective voltage level upon said one of said plurality of input/output pads, and wherein said plurality of input/output pads are serially coupled for receiving signals representative of said plurality of high impedance states.

A method of programming a plurality of pullup and pulldown devices associated with a plurality of input/output pads, comprising:

• storing received data indicative of a high impedance state for each of said plurality of input/output pads;
• shifting said received data to said input/output pads wherein a respective one of said plurality of input/output pads receives respective ones of said received data representative of a respective one of said high impedance states;
• and
• latching said respective ones of said received data into said plurality of pullup and pulldown devices such that said pullup and pulldown devices are enabled according to said respective ones of said high impedance states.

An apparatus for programming high impedance states, comprising:

• a plurality of registers for storing a plurality of control bits;
• a master register/slave latch coupled to store one of said plurality of control bits during a shift clock transition;
• and
• a transistor having a gate terminal and a source-drain path, said gate terminal is coupled to receive an output of said master register/slave latch, and said source-drain path is coupled between an input/output pad and a power supply.