Abstract:
A reset initialization structure and method is described. A power on reset pulse is utilized to force the state of system reset during intervals of Vcc which otherwise would result in indeterminate reset states. Operation is adaptable to include all DC power systems. The reset initialization structure provides operational protection during power up and power down conditions.
Abstract:
A trenching machine having independently driven wheels. Trenching machine comprises digging chain that moves between a raised position and a lowered position, a housing that is carried by a pair of front wheels and a pair of rear casters, a motor that independently drives front wheels to propel housing, and a guide wheel that aligns trenching machine with trench upon a second pass. Trenching machine also has a front plow and a rear plow that collect and deposit the dirt surrounding the trench into the trench. A method of gardening/landscaping wherein a trench is dug by a first pass, soil amendments are added to the trench, and then on the second pass, the excavated dirt is plowed back into the trench and then mixed with the amendments. A method of gardening/landscaping wherein vegetation cover between trenched rows is maintained thus utilizing only the ground area that is needed for planting.
Abstract:
A power-on reset circuit. The power-on reset circuit includes a switch, a current source coupled between a first potential and a switch first contact; a resistive device having a resistive-device first contact coupled to the first potential; a first module coupled between a second potential and a switch second contact; a second module coupled between the second potential and resistive-device second contact; and an inverter having an inverter input coupled to the resistive-device second contact. Current through the second module mirrors current through the first module. If a first mirrored potential of the second potential present on a switch control contact is greater than a preselected value, the switch first contact is coupled to the switch second contact. Otherwise, the switch first contact is decoupled from the switch second contact.
Abstract:
A battery monitor circuit. The circuit includes a control module, a resistive load having a resistive value between a first and a second terminals and a part of that resistive value between the first and an intermediate terminals, a switch configured to couple the full load between circuit input and a common potential in response a pulse signal, a first comparator having inputs separately coupled to a voltage reference and the intermediate terminal, a second comparator having inputs separately coupled to the voltage reference and an input potential, a latch, a detection module having input coupled to second comparator output, and an alarm module. The latch is configured to latch a value at output of first comparator to another input of the detection module in response to the pulse signal; if input potential is less than a preselected magnitude, detection module output is configured to activate the alarm module.
Abstract:
A power-on reset circuit. The power-on reset circuit includes a switch, a current source coupled between a first potential and a switch first contact; a resistive device having a resistive-device first contact coupled to the first potential; a first module coupled between a second potential and a switch second contact; a second module coupled between the second potential and resistive-device second contact; and an inverter having an inverter input coupled to the resistive-device second contact. Current through the second module mirrors current through the first module. If a first mirrored potential of the second potential present on a switch control contact is greater than a preselected value, the switch first contact is coupled to the switch second contact. Otherwise, the switch first contact is decoupled from the switch second contact.
Abstract:
A reset ramp control structure and method is described. A fast ramp down condition of a monitored voltage is detected and used to force the state of system reset. Delay between fast ramp detection and the forcing of system reset is adjustable. Operation is adaptable to include all DC power systems. The reset ramp control structure provides operational protection during fast ramp down conditions when standard reset circuitry may not be operational.
Abstract:
An electronic device incorporates a primary function circuit and a voltage regulator that provides a regulated voltage signal to the primary function circuit. The voltage regulator is responsive to a stress-enable signal indicative of whether or not an external voltage supplied to the voltage detector is within a predetermined range. The output voltage signal is controlled to be at a first voltage level when the external voltage is within the predetermined voltage range and at a second voltage level when the external voltage is outside of the predetermined range. The second voltage level may be an elevated voltage level to facilitate stress testing or burin-in of the electronic device.
Abstract:
A threshold personalization circuit for a reset or supervisor chip includes personalization fuses, which shift a resistor divider to provide a variety of selectable voltage thresholds. The personalization fuses may provide hundreds of millivolts of adjustment. The threshold personalization circuit further includes trim fuses to fine tune the threshold to within a few millivolts of the target threshold voltage. The threshold personalization circuit includes a test mode to cycle through to a particular personalization trim, such that at prelaser testing the personalized value is found (the fuse blow for personalization is emulated) and then the trim fuse amount can be based on the actual final personalized voltage. This results in very accurate threshold voltages for all personalized values.
Abstract:
An integrated circuit temperature sensor includes a sensing circuit operable to determine whether the integrated circuit is currently exposed to one of a relatively low temperature or a relatively high temperature. A selection circuit operates to select a measured voltage across the base-emitter of a bipolar transistor of the integrated circuit if the sensing circuit indicates that the integrated circuit is currently exposed to the relatively low temperature or, alternatively, select a measured delta voltage across the base-emitter of the bipolar transistor of the integrated circuit if the sensing circuit indicates that the integrated circuit is currently exposed to the relatively high temperature. A comparator then compares the selected measured voltage across the base-emitter of the bipolar transistor against a first reference voltage indicative of a too cold temperature condition or compares the selected measured delta voltage across the base-emitter of the bipolar transistor against a second reference voltage indicative of a too hot temperature condition. As a result of the comparison, detection may be made as to whether the integrated circuit is currently exposed to one of either a too cold or too hot temperature.
Abstract:
An integrated circuit temperature sensor includes a sensing circuit operable to determine whether the integrated circuit is currently exposed to one of a relatively low temperature or a relatively high temperature. A selection circuit operates to select a measured voltage across the base-emitter of a bipolar transistor of the integrated circuit if the sensing circuit indicates that the integrated circuit is currently exposed to the relatively low temperature or, alternatively, select a measured delta voltage across the base-emitter of the bipolar transistor of the integrated circuit if the sensing circuit indicates that the integrated circuit is currently exposed to the relatively high temperature. A comparator then compares the selected measured voltage across the base-emitter of the bipolar transistor against a first reference voltage indicative of a too cold temperature condition or compares the selected measured delta voltage across the base-emitter of the bipolar transistor against a second reference voltage indicative of a too hot temperature condition. As a result of the comparison, detection may be made as to whether the integrated circuit is currently exposed to one of either a too cold or too hot temperature. In a test mode, the circuit is exposed to a readily available temperature, such as room temperature, and the measured delta voltage across the base-emitter and/or the measured voltage across the base-emitter are scaled in accordance with that available temperature for application to the comparator. Alternatively, in test mode the reference voltages are scaled to intersect with the measured delta voltage across the base-emitter and/or the measured voltage across the base-emitter at the available temperature.