Abstract: A low-voltage, low-power DC voltage generator system is provided having two negative voltage pump circuits for generating voltages for operating negative wordline and substrate bias charge pump circuits, a reference generator for generating a reference voltage, and a two-stage cascaded positive pump system having a first stage pump circuit and a second stage pump circuit. The first stage converts a supply voltage to a higher voltage level, e.g., one volt to 1.5 volts, to be used for I/O drivers, and the second stage converts the output voltage from the first stage to a higher voltage level, e.g., from 1.5 volts to about 2.5 volts, for operating a boost wordline charge pump circuit. The DC voltage generator system further includes a micro pump circuit for providing a voltage level which is greater than one-volt to be used as reference voltages, even when an operating voltage of the DC voltage generator system is at or near one-volt.

Abstract: A low-voltage, low-power DC voltage generator system is provided having two negative voltage pump circuits for generating voltages for operating negative wordline and substrate bias charge pump circuits, a reference generator for generating a reference voltage, and a two-stage cascaded positive pump system having a first stage pump circuit and a second stage pump circuit. The first stage converts a supply voltage to a higher voltage level, e.g., one volt to 1.5 volts, to be used for I/O drivers, and the second stage converts the output voltage from the first stage to a higher voltage level, e.g., from 1.5 volts to about 2.5 volts, for operating a boost wordline charge pump circuit. The DC voltage generator system further includes a micro pump circuit for providing a voltage level which is greater than one-volt to be used as reference voltages, even when an operating voltage of the DC voltage generator system is at or near one-volt.

Abstract: Wafer test and burn-in is accomplished with state machine or programmable test engines located on the wafer being tested. Each test engine requires less than 10 connections and each test engine can be connected to a plurality of chips, such as a row or a column of chips on the wafer. Thus, the number of pads of the wafer that must be connected for test is substantially reduced while a large degree of parallel testing is still provided. The test engines also permit on-wafer allocation of redundancy in parallel so that failing chips can be repaired after burn-in is complete. In addition, the programmable test engines can have their code altered so test programs can be modified to account for new information after the wafer has been fabricated. The test engines are used during burn-in to provide high frequency write signals to DRAM arrays that provide a higher effective voltage to the arrays, lowering the time required for burn-in.

Abstract: Wafer test and burn-in is accomplished with state machine or programmable test engines located on the wafer being tested. Each test engine requires less than 10 connections and each test engine can be connected to a plurality of chips, such as a row or a column of chips on the wafer. Thus, the number of pads of the wafer that must be connected for test is substantially reduced while a large degree of parallel testing is still provided. The test engines also permit on-wafer allocation of redundancy in parallel so that failing chips can be repaired after burn-in is complete. In addition, the programmable test engines can have their code altered so test programs can be modified to account for new information after the wafer has been fabricated. The test engines are used during burn-in to provide high frequency write signals to DRAM arrays that provide a higher effective voltage to the arrays, lowering the time required for burn-in.

Abstract: An embedded memory macro device includes a memory system and a logic circuit constructed on a common semiconductor substrate. The memory system and logic circuit communicate through a handshake procedure via a system data interlock signal. During read cycles the memory system uses the system data interlock signal to tell the logic circuit when data at memory system data outputs is valid. In the preferred embodiment, during write cycles the memory system uses the system data interlock signal to tell the logic circuit when data has been successfully written. The logic circuit needs to wait only until the system data interlock signal permits it to proceed. It then signals the memory system to reset the system data interlock signal and can immediately initiate a new read or write cycle.

Abstract: A power up detection circuit is provided which includes a power supply terminal, an output terminal, an impedance device coupling the output terminal to the power supply terminal and a latch including a first inverter having a first device connected between the output terminal and a point of reference potential and a second device connected between the output terminal and the power supply terminal, the devices are designed so that subthreshold current passing through the first device is greater than the effective subthreshold current passing through the impedance device and the second device, and a second inverter including third and fourth devices which are designed so that a smaller subthreshold current passes through the third device than the subthreshold current passing through the fourth device. The power up circuit may further include a capacitor connected between the power supply terminal and gate electrodes of the first and second devices.

Abstract: A built-in, i.e., on-chip, self-test system for a VLSI logic or memory module. A deterministic data pattern generator is provided on the VLSI chip, and operates to test a chip module and provide a fail/no-fail result, along with data identifying where the fail occurred. This location data is captured and made available for subsequent utilization. The built-in test circuitry is programmable, and is provided with a looping capability to provide enhanced burn-in testing, for example.

Abstract: A test selection system is provided which includes a semiconductor substrate having a pin connected thereto and an integrated circuit disposed on the substrate and connected to the pin having an operating voltage within a given voltage range. A latch conditioning circuit having an input responsive to a voltage of a given magnitude has an output connected to a latch, and a voltage control circuit operable at a voltage without the given voltage range selectively applies a control voltage of the given magnitude to the input of the latch conditioning circuit. A voltage without the given voltage range is applied to the pin during a first interval of time to produce the control voltage for establishing a test mode and a voltage within the given voltage range is applied to the pin during a second interval of time to establish a normal operating mode for the integrated circuit.

Abstract: A power supply adapter system is provided which includes a voltage supply source terminal, an output terminal, first and second switches, the first switch being disposed between the voltage supply source terminal and the output terminal, voltage conversion means serially connected with the second switch and disposed between the voltage supply source terminal and a point of reference potential and having an output coupled to the output terminal, and means for detecting first and second ranges of voltages at the power supply source terminal and for producing first and second control voltages, respectively, to control the first and second switches.

Abstract: An off-chip driver circuit is provided which includes a pull-up device disposed between an output terminal and a first voltage dropping diode which is connected to a first voltage supply source and a first voltage limiting circuit connected to the common point between the pull-up device and the voltage dropping diode. The off-chip driver circuit further includes an input inverter circuit having an output connected to the control element of the pull-up device. The inverter circuit has a P-channel field effect transistor and an N-channel field effect transistor serially connected with a second voltage dropping diode which is connected to the first voltage supply source and a second voltage limiting circuit connected to the common point between the second voltage dropping diode and the P-channel field effect transistor of the input inverter.