Abstract: A high speed test circuit receives a tester clock from a tester and it conducts a test on a circuit under test. The high speed test circuit generates a high frequency clock according to the tester clock, so it is capable of operating in two frequencies. The high speed test circuit tests the circuit under test according to the high frequency clock, and it performs a low speed operation according to a low frequency clock, which is for example the tester clock.

Abstract: A high speed test circuit receives a tester clock from a tester and it conducts a test on a circuit under test. The high speed test circuit generates a high frequency clock according to the tester clock, so it is capable of operating in two frequencies. The high speed test circuit tests the circuit under test according to the high frequency clock, and it performs a low speed operation according to a low frequency clock, which is for example the tester clock.

Abstract: A method for a deep power down mode is described for a memory chip in which voltage regulators and charge pumps are turned off, memory cell voltages are floated, and support circuit internal power supply voltages are replaced by voltages that are derived from the external chip voltage. Prior to being placed into a deep power down mode, all memory cells are placed into a precharge state from which the memory cell voltages are floated upon entering the deep power down mode. Pass through circuits connect externally derived voltages to the support circuit power supply voltage lines, controlled by a deep power down signal. Maintaining a voltage bias on the support circuits prevents latch up problems when the memory chip is brought out of the deep power down mode.

Abstract: A method and apparatus are provided for improving the efficiency in charge pump systems for low power applications. This first embodiment provides a method and apparatus which defines a charge pump output voltage high target which turns off a charge pump enable signal and a charge pump outlet voltage low target which turns on a charge pump enable signal. A second embodiment defines a protection time where the charge pumping continues until a predefined phase is completed and the leakage paths are disabled. A third embodiment defines a phase memory block, which continues or remembers the phase until the next request for charge pumping. This prevents the circuitry from entering a window where charge leakage, which diminishes charge pumping efficiency, could occur.

Abstract: A method for a deep power down mode is described for a memory chip in which voltage regulators and charge pumps are turned off, memory cell voltages are floated, and support circuit internal power supply voltages are replaced by voltages that are derived from the external chip voltage. Prior to being placed into a deep power down mode, all memory cells are placed into a precharge state from which the memory cell voltages are floated upon entering the deep power down mode. Pass through circuits connect externally derived voltages to the support circuit power supply voltage lines, controlled by a deep power down signal. Maintaining a voltage bias on the support circuits prevents latch up problems when the memory chip is brought out of the deep power down mode.