Abstract: An electric motor control with integral battery charger includes battery terminals (201) for connection to a battery (203). A boost converter circuit (111) is coupled to an armature winding (209) of the electric motor (117), and has an input (131) coupled to a power source (211). A buck converter circuit (105) is coupled to a field winding (207) of the electric motor (117), and an input (133) coupled to the power source (211). A controller (205), is coupled to the battery terminals (201) and the power source (211). The controller (205) couples a boost output (107) of the boost converter circuit (111 ) to the battery terminals (201) while a terminal voltage of the power source (211) is lower than a terminal voltage of the battery (203) measured at the battery terminals (201), and couples a buck output (107) of the buck converter circuit (105) to the battery terminals (201 ) while the terminal voltage of the power source (211) is higher than the terminal voltage of the battery (203).

Abstract: A DC power switch (10) for a capacitive load (11) has a main transistor (Q1) in series with the load between positive and negative DC bus terminals (B.sup.+, B.sup.-). A secondary transistor (Q2) and a resistor (R.sub.1) are connected in series and this series connection is connected in parallel to the main transistor (Q1). A control circuit (20; 50) is connected to the main and secondary transistors (Q1, Q2) and controls them. In response to an enable signal (26), the secondary transistor (Q2) is initially turned on such that it and the resistor provide the initial charging current for the capacitor load (11) and subsequently the secondary transistor is turned off and the main transistor is turned on such that it provides the subsequent current required by the load. This configuration minimizes the power dissipation ratings required for the transistors while balancing this requirement with the relative rapid providing of charging current for the capacitive load.

Abstract: Disclosed is an ignition signal control apparatus and method for a distributorless ignition system of the type having a sensing circuit which generates at least one reference signal which may be used to periodically indicate when ignition spark plugs should be fired, and at least one identifier signal determinative of the engine's crank angle position to identify the spark plug firing sequence. One aspect of the invention includes detecting that a transition in the identifier signal has not occurred, and generating a replacement signal independent of the crank angle position, to select one or more of the spark plugs to fire.

Abstract: An invention for detecting loss of input signals to a distributorless ignition system (17) and for providing appropriate responses upon detecting fault conditions. If a SPOUT signal (31) faults low, the invention will control ignition sequence through use of a CID signal (14), and the CID signal (14) and a PIP signal (13) will be operably substituted for the missing SPOUT signal (31) to assure timely ignition. If the SPOUT signal (31) faults high, the CID signal (14) will again be utilized to sequence the firing sequence and the PIP signal (13) will be substituted for the SPOUT signal (31). If the CID signal (14) faults, firing sequence will continue to be incremented in response to receipt of the SPOUT signal (31). In addition, the invention provides for recovery of normal operation should any of the above fault conditions prove to be transient.

Abstract: An overcurrent protection circuit for inductive loads such as motors is provided. A source voltage is input to a divider circuit including semiconductor switching devices. The inductive load is also connected to the voltage source through the divider circuit. A voltage output from the divider circuit which is proportional to the current through the inductive load is input to a comparator circuit. Another input to the comparator circuit comprises a reference voltage selected to correspond to the maximum desired current through the inductive load. If the comparator circuit senses that the current through the inductive load is greater than the predetermined maximum current, it provides an output to a pulse generator device. The output from the pulse generator device is input to a switching circuit which can cut off the voltage source supply to the inductive load.