摘要:
The present invention includes a MOS device (100) that has a P-type substrate (102) and an N-type drain region (104) formed within the substrate (102). An annular N-type source region (106) generally surrounds the drain region (104). The source region (106) serves as both the source for the MOS device (100) and a sacrificial collector guard ring for an electrostatic discharge protection circuit. An annular gate region (110) generally surrounds the drain region (104) and is electrically insulated from the drain region (104) and electrically connected to the source region (106). An annular P-type bulk region (108) generally surrounds the source region (106) and is electrically connected to the source region (106).
摘要:
A method evaluating threshold of a data cell in a memory device including a programming locus coupled with the data cell for receiving a programming signal setting a stored signal level in the data cell and responding to a read signal to indicate the stored signal at a read locus; includes the steps of: (a) in no particular order: (1) selecting a test threshold signal; and (2) setting a read signal at a non-read level; (b) applying the test threshold signal to the programming locus; (c) cycling the read signal between a read level and a non-read level while applying the test threshold signal to the programming locus to present at least two test signals at the read locus when the read signal is at the read level; and (d) while cycling, observing whether the at least two test signals manifest a difference greater than a predetermined amount.
摘要:
A method evaluating threshold of a data cell in a memory device including a programming locus coupled with the data cell for receiving a programming signal setting a stored signal level in the data cell and responding to a read signal to indicate the stored signal at a read locus; includes the steps of: (a) in no particular order: (1) selecting a test threshold signal; and (2) setting a read signal at a non-read level; (b) applying the test threshold signal to the programming locus; (c) cycling the read signal between a read level and a non-read level while applying the test threshold signal to the programming locus to present at least two test signals at the read locus when the read signal is at the read level; and (d) while cycling, observing whether the at least two test signals manifest a difference greater than a predetermined amount.
摘要:
A method evaluating threshold of a data cell in a memory device including a programming locus coupled with the data cell for receiving a programming signal setting a stored signal level in the data cell and responding to a read signal to indicate the stored signal at a read locus; includes the steps of: (a) in no particular order; (1) selecting a test threshold signal; and (2) setting a read signal at a non-read level; (b) applying the test threshold signal to the programming locus; (c) cycling the read signal between a read level and a non-read level while applying the test threshold signal to the programming locus to present at least two test signals at the read locus when the read signal is at the read level; and (d) while cycling, observing whether the at least two test signals manifest a difference greater than a predetermined amount.
摘要:
A switch-mode power regulator includes a turn-on controller 52 to limit, during a fixed period of time, the initial current passing through the regulator following turn-on. During this time period the storage elements of the regulator must achieve an acceptable level of stability without excessive current flow. Turn-on controller 52 comprises a divider 72 which clocks zeroes along the length of a shift register 74 which is initially preset to all ones. The outputs of the shift register are coupled to a decoder 76, whose input signals are sequentially steered to its output under the control of a counter 70. The output signal from decoder 76 functions as the power regulator switching signal from turn-on controller 52. Counter 70 cycles many times for each data shift of shift register 74. Thus, turn-on controller 52 generates a train of negative pulses which increase in length monotonically for the duration of the sequence. In one embodiment, the first two data inputs of decoder 76 are grounded, thereby providing a fixed minimum pulse width at the onset of the sequence. In another embodiment, the last two data inputs of decoder 76 are tied to logic supply voltage, thereby preventing cycle skipping.
摘要:
A method evaluating threshold of a data cell in a memory device including a programming locus coupled with the data cell for receiving a programming signal setting a stored signal level in the data cell and responding to a read signal to indicate the stored signal at a read locus; includes the steps of: (a) in no particular order: (1) selecting a test threshold signal; and (2) setting a read signal at a non-read level; (b) applying the test threshold signal to the programming locus; (c) cycling the read signal between a read level and a non-read level while applying the test threshold signal to the programming locus to present at least two test signals at the read locus when the read signal is at the read level; and (d) while cycling, observing whether the at least two test signals manifest a difference greater than a predetermined amount.
摘要:
Systems, methods and circuits for regulator minimum load control. In one particular case, a system is provided that includes a load control circuit and a switched load. The load control circuit includes a reference current, and a sense current representative of a load current. In addition, the load control circuit includes a comparator circuit that drives a control signal in response to a comparison between the reference current and the sense current. The switched load is electrically coupled to a load voltage signal to provide loading to the load voltage signal. The switched load is operable to switch between a first loading factor and a second loading factor in response to the control signal.
摘要:
System and method for controlling current across a load. A preferred embodiment comprises a current varying circuit (such as current varying circuit 525) that can create a sequence of voltage drops in a driver circuit (such as the driver circuit 505) coupled to an inductive load (such as the inductive load 535). By initially producing a large voltage drop and then stepping the voltage drop down gradually, the current in the inductive load can be rapidly removed without producing a current undershoot, which, in certain applications, can result in unwanted noise and vibration.
摘要:
System and method for controlling current across a load. A preferred embodiment comprises a current varying circuit (such as current varying circuit 525) that can create a sequence of voltage drops in a driver circuit (such as the driver circuit 505) coupled to an inductive load (such as the inductive load 535). By initially producing a large voltage drop and then stepping the voltage drop down gradually, the current in the inductive load can be rapidly removed without producing a current undershoot, which, in certain applications, can result in unwanted noise and vibration.
摘要:
A circuit for programming an EEPROM 42 which is used to provide trim adjustment for an integrated circuit (IC). The programming circuit provides the capability of programming the EEPROM 42 indefinitely, employing interfaces which are available even after the IC is packaged and encapsulated. Furthermore, it provides the manufacturer or enduser the capability of disabling the programming function permanently, to thereby prevent any inadvertent modifications of the EEPROM 42 data. The programming circuit includes a one-bit EEPROM 32, a nonvolatile memory element which retains its programmed logic state whether or not it is powered up. EEPROM 32 is set during final probe test by the application of a voltage to a probe pad 30 coupled to its set input terminal. Probe pad 30 is exposed such that it may be contacted by a probe prior to IC encapsulation, but is inaccessible after encapsulation. So long as EEPROM 32 is set, EEPROM 42 may be modified upon receipt of a unique address from the system data bus followed by programming data for EEPROM 42. When EEPROM 32 is reset, the programming function of EEPROM 42 is permanently disabled. In a first embodiment, EEPROM 32 is reset by setting a predetermined one of the EEPROM 42 bits to a specified logic state. In a second embodiment, EEPROM 32 is reset by the receipt of another unique address decode from the system data bus.