Abstract: A system and methods for controlling power flow between a first and a second power supplies and an appliance. A first switch is coupled to the first power supply for switching power flow between the first power supply and the appliance. A second switch is coupled to the second power supply for switching power flow between the second power supply and the appliance. A first controller circuit is coupled to the first switch and the first power supply for monitoring at least one parameter of the first power supply and actuating the first switch to cease power flow if the at least one monitored parameter exceeds a given value, or deviates from a range of values. A second controller circuit is coupled to the first controller circuit, the second switch, and the second power supply for monitoring at least one parameter of the second power supply and actuating the second switch to cease power flow if the at least one monitored parameter exceeds a give value, or deviates from a given range.

Abstract: A reconfigurable integrated circuit chip includes an output terminal (42) which is connected to the output of an inverting amplifier (44). The integrated circuit chip (10) includes an output terminal (46) which is connected to one input of a comparator (22). The other end of comparator (22) is connected to an internal voltage reference device (48). The output of comparator (22) is connected to the input of the inverting amplifier (44). The integrated circuit chip (10) may be configured as a linear regulator when a transconductance device (14) is connected between a DC power supply (12) and a load and an integrator (24) is connected between terminal (42) and the control input of the transconductance device (14). The integrated circuit chip (10) is configured as a switching regulator when a gated switch (14) is connected between a DC power supply (12) and a switching node (65) wherein the gated switch (14) is gated by the signal output by the output terminal (42).

Abstract: A battery monitoring/control device includes a monitor/control device (35) that is operable to be integrated with a microprocessor system. The system includes a CPU (12) that interfaces with a data bus (14) and an address bus (16). The CPU (12) interfaces through a data line (40) with the control/monitor device (35) and control lines (28) and (34). Commands and data can be input to the control/monitor circuit (35) and data received therefrom. The control/monitor device (35) includes a controller/data register block (36) and a battery charge control/monitor block (44). The device (35) is operable to monitor the battery voltage of a secondary battery (46) during charging thereof and to control the rate of charge through a transistor (66). The battery monitor (90) determines when the voltage on the battery (46) reaches a predetermined level indicating full-charge.

Abstract: The low power voltage comparator with hysteresis includes a comparator (10) that is operable to receive the output from a battery (14) on the positive input thereof and the output of a battery (16) on the negative input thereof. An offset circuit (22) is provided in series with the voltage of the battery (14) and the comparator (10), and an offset circuit (24) is provided between the battery (16) and the comparator (10). The offset circuits (22) and (24) are adjustable by a hysteresis control circuit (26) to offset the voltage thereof for the non-selected battery to be higher than that for the selected battery such that the voltage drop across the offset for the non-selected battery is greater than that for the selected battery. When the voltage on the selected battery falls below the offset voltage of the non-selected battery, the hysteresis control then decreases the offset upon selecting the other battery and increases the offset or the battery that is deselected.

Abstract: A fuse state sense circuit includes a fusible link (40) that is disposed between a node (38) and ground. A programming/sense pad (42) is provided to allow voltage to be applied to the node (38) external to the fuse state sense circuit. Current is provided to the node (38) through a current source (30) and a transistor (36). The transistor (36) is controlled by a bias current. An output node (32) is disposed between the current source (30) and the transistor (36). This is connected to the output through an inverter (34). In operation, the voltage on node (38) is raised to a first level to turn off transistor (36) to allow the output to be exercised and to change the state thereof to emulate the fusible link (40) being open. In a second and programming mode, the voltage on the node (38) is raised to a much higher level to allow sufficient current to flow through fusible link (40) to open it.

Abstract: A power resource management system includes a battery charging system (20) that is connected between a positive voltage terminal and a voltage sense terminal (15). An operating system (10), that in one mode operates off of the battery and in a second and charging mode operates off the power source (24), is connected between the positive terminal (12) and the voltage sense node (15). A sense resistor (16) is connected between the voltage sense node (15) and a ground terminal (18). The power source (24) is operable to deliver voltage across the positive terminal (12) and the negative terminal (18). The battery charger (20) includes a charge modulator (24) and a buck regulator which has a switch (26) that is controlled by the controller (34).

Abstract: A differential comparator is provided for controlling two switches (40) and (42) to switch two supplies (10) and (12), respectively, to a common output node (22). The decision/control circuit (44) outputs two control signals (46) and (48), the logic state thereof being a function of whether supply (10) is higher than supply (12) or supply (12) is higher than supply (10). The operating power for the decision/control circuit (44) is derived from the supplies (10) and (12), and not from the common output node (22), such that when the switches (40) and (42) are closed and no power is being supplied by either of the supplies (10) and (12), the decision/control circuit (44) has sufficient power to make a decision.