Abstract: A method of adaptively controlling a charge pump including coupling the charge pump to a control node, toggling a clock input between supply voltage levels to charge an a charge pump output, monitoring the charge pump output, maintaining the control node at a supply voltage level when a supply voltage magnitude does not exceed a threshold level, and adjusting the control node to maintain the charge pump output at a limit level when the supply voltage magnitude exceeds the threshold level. A positive charge pump embodiment charges the output to twice the positive supply voltage up to no more than a limit level. A negative charge pump embodiment charges the output to the same magnitude with opposite polarity as the positive supply voltage, and decreases the output magnitude if the positive supply voltage is above the threshold level. A Zener diode and controlled current mirror may be used for control.

Abstract: A body control apparatus for an analog switch for minimizing leakage current and keeping PN junctions reverse-biased. The analog switch has first and second switch device clusters coupled between input and output nodes and controlled by a control input, each having a corresponding body junction. The body control apparatus includes body control devices each controlled by one of the input and output nodes for coupling a body junction to the opposite one of the input and output nodes. Each switch device cluster may include a main switch and body devices which keep the body junction of the main switch at a voltage level between the input and output nodes when the analog switch is on. When the analog switch is off, the body control apparatus activates when voltage across the input and output nodes rises to keep the body junctions at desired voltage levels.

Abstract: A method of adaptively controlling a charge pump including coupling the charge pump to a control node, toggling a clock input between supply voltage levels to charge an a charge pump output, monitoring the charge pump output, maintaining the control node at a supply voltage level when a supply voltage magnitude does not exceed a threshold level, and adjusting the control node to maintain the charge pump output at a limit level when the supply voltage magnitude exceeds the threshold level. A positive charge pump embodiment charges the output to twice the positive supply voltage up to no more than a limit level. A negative charge pump embodiment charges the output to the same magnitude with opposite polarity as the positive supply voltage, and decreases the output magnitude if the positive supply voltage is above the threshold level. A Zener diode and controlled current mirror may be used for control.

Abstract: A body control apparatus for an analog switch for minimizing leakage current and keeping PN junctions reverse-biased. The analog switch has first and second switch device clusters coupled between input and output nodes and controlled by a control input, each having a corresponding body junction. The body control apparatus includes body control devices each controlled by one of the input and output nodes for coupling a body junction to the opposite one of the input and output nodes. Each switch device cluster may include a main switch and body devices which keep the body junction of the main switch at a voltage level between the input and output nodes when the analog switch is on. When the analog switch is off, the body control apparatus activates when voltage across the input and output nodes rises to keep the body junctions at desired voltage levels.

Abstract: A switch circuit including a first switch, a reference device, a current generating device and a comparator. The first switch has a first resistance and develops a first voltage when a first current is provided through it. The reference device has a second resistance which is a known multiple of the first resistance. The current generating device provides a reference current through the reference device which develops a second voltage having a level indicative of a maximum current level of the first current. The comparator compares the first and second voltages and provides a maximum current indication. An amplifier may be used to force one side of the first switch and the reference device to the same voltage, where the reference device is coupled between an input and an output of the amplifier. The switch circuit may include a calibration mode.

Abstract: An integrated analog switch including first and second semiconductor devices and a current mirror. The first device is a switching device having first and second current terminals coupled between first and second switch terminals. When turned off, the body of the first device is pulled to a bias voltage, and a first leakage current flows between its body and the first switch terminal. The second device is a reduced-size replica of the first device having one current terminal coupled to the first switch terminal and having its body pulled to about the bias voltage when turned off. The second device provides a second leakage current which is proportional to the leakage current of the first device. The current mirror circuit mirrors and amplifies the second leakage current to provide a cancellation current which is applied to the first switch terminal to cancel leakage current.

Abstract: A switch circuit, which selectively couples first and second switch nodes together and which enables the first and second switch nodes to operate in an extended voltage range, includes a secondary voltage rail, a switch device, a body driver, a rail control switch, and a switch control circuit. The rail control switch clamps the secondary voltage rail to a primary voltage rail during normal voltage range operation, but otherwise releases the secondary voltage rail to float. The body driver clamps the body of the switch to the secondary voltage rail when turned on, and when turned off, forward biases to allow voltage of said secondary voltage rail to follow voltage of the switch nodes into the extended voltage range through the switch. The switch control circuit includes a latch circuit which ensures that the switch remains either turned on or turned off during extended voltage operation.

Abstract: A series of compounds of Formula I which have anti-tumor activity, and are useful in treating viral infections, their compositions and use. ##STR1## In Formula I B is a purine or pyrimidine base; alk.sub.1 alk.sub.2 and alk.sub.3 are chemical bonds or alkylene groups; Q is hydrogen or hydroxyl; and R.sub.1 -R.sub.4 are hydrogen or alkyl.

Abstract: A series of compounds of Formula I which have anti-tumor activity, and are useful in treating viral infections, their compositions and use. ##STR1## In Formula I B is a purine or pyrimidine base; alk.sub.1 alk.sub.2 and alk.sub.3 are chemical bonds or alkylene groups; Q is hydrogen or hydroxyl; and R.sub.1 -R.sub.4 are hydrogen or alkyl.

Abstract: A current mode (NOR) logic circuit includes a first, fixed reference current source transistor stage coupled in circuit between a first voltage supply terminal and an input current node. A second, variable current source transistor stage is coupled in circuit between the first voltage supply terminal and the input current node. The second, variable current source supplies a variable quantity of auxiliary current to the input current node in dependence upon whether the input node sees a high logical level current or a low logic level current. The magnitude of the auxiliary current is such that the total of the auxiliary current and the prescribed reference current balances the input current being supplied to the input current node. A current switch transistor has its collector-emitter current flow path coupled in circuit between the first current source and one or more output current transistors.

Abstract: An electrical winch mounted to a drawbar having at one end a receptacle and at the other end a stub. The winch drawbar can be connected between a vehicle hitch and a ball-type hitch member which is then adapted for supporting pulling and downward loads. A trailer can be connected to the ball so that the winch can be utilized to pull loads onto the trailer. Because the winch is load bearing, the loaded trailer can be repositioned or towed at low speeds, via the winch, by the vehicle. Front and rear-mounted hitches allow the winch to be releasably attached thereto for self recovery of the vehicle from either direction.

Abstract: An input circuit for an operational amplifier which incorporates a bias control transistor for effectively minimizing the input current to a Darlington-connected transistor pair into the same semiconductor region in which the Darlington-connected transistor pair is formed. All portions of the surface of the dielectrically isolated island are effectively boot-strapped with the (common mode) input signal, whereby the parasitic capacitance to ground is effectively eliminated. This enables the collector current of the input transistor to be reduced significantly relative to the collector current flowing through the output transistor of the Darlington pair. To accommodate for device characteristic variations among separate wafer processing runs, a self-balanced bias circuit, containing a transistor pair matched to the bias and Darlington output transistors, is employed as the current source of the operational amplifier.