June 6, 2001 - Following the introduction of the industry's smallest full-function supervisory IC family, National Semiconductor (NYSE:NSM) today introduced three new supply voltage supervisory circuits with factory-programmability for easy configurations and system integrity. The EEPROM technology used in the three new circuits allows National to deliver low-power, custom silicon quickly to designers for space-constrained portable and battery-powered applications such as personal digital assistants (PDAs), cellular phones and information appliances. These devices are available in both extended temperature range -40 to 125?C and industrial temperature range -40 to 85?C, enabling applications to go anywhere.
"Using EEPROM technology to customize the threshold voltage, National is giving designers all the flexibility they need in choosing optimal supervisory functions," said Maria Laughlin, marketing manager of National Semiconductor's Power Management group. "The three new devices meet market requirements for low power and small footprint, offering our customers complete supervisory IC solutions in their portable designs."
As part of the LM37xx supervisory IC family, National's LM3722, LM3723 and LM3724 are all in the SOT23-5 packaging. With low supply current of only 6uA and a guaranteed reset output valid down to 1V, these new supervisory circuits are used to monitor the supply voltage. Asserting a reset signal whenever the voltage supply drops below the predetermined set point, the reset remains active for at least 100 ms after supply voltage rises above the threshold voltage. This reset comparator avoids problems due to transients on the supply voltage line.
The LM3722 has totem pole output (push-pull) with active-low reset output, the LM3723 has a totem pole output with active-high reset output, while the LM3724 has an open-drain with active-low reset bar output. The standard voltages for these circuits are 4.63V, 3.08V and 2.32V. Additional threshold voltages between 2.2 and 5.0V in steps of 10mV are also available.
Pricing and Availability
The three new supervisory circuits, the LM3722, the LM3723 and the LM3724 in industrial temperature range, are available now in the SOT23-5 packaging and are priced at $0.80 each in 1,000 units. For more information on National's family of supply voltage supervisory ICs, visit National's World Wide Web site at http://www.national.com/pf/LM/LM3722.html, http://www.national.com/pf/LM/LM3723.html and http://www.national.com/pf/LM/LM3724.html.
About National Semiconductor
National Semiconductor is the premier analog company driving the information age. Combining real-world analog and state-of-the-art digital technology, the company is focused on the fast growing markets for wireless handsets; information appliances; information infrastructure; and display, imaging and human interface technologies. With headquarters in Santa Clara, California, National reported sales of $2.1 billion for its last fiscal year and has about 10,000 employees worldwide. Additional company and product information is available on the World Wide Web at www.national.com.
