National Semiconductor Manuals

LP38691/3-ADJ is a low dropout CMOS linear regulator with adjustable output and stable performance with ceramic output capacitors. It provides a 2.0% precision reference voltage, extremely low dropout voltage (250mV @ 500mA load current, VOUT = 5V), and excellent AC performance. It is suitable for applications such as hard disk drives, notebook computers, battery-powered devices, and portable instrumentation.

The LP38691/3 low dropout CMOS linear regulators provide tight output tolerance, extremely low dropout voltage, and excellent AC performance utilizing ultra low ESR ceramic output capacitors. The low thermal resistance of the LLP, SOT-223 and T0-252 packages allow the full operating current to be used even in high ambient temperature environments. The use of a PMOS power transistor means that no DC base drive current is required to bias it allowing ground pin current to remain below 100 µA regardless of load current, input voltage, or operating temperature.

This document introduces the features and characteristics of the LP38690/LP38692 1A low dropout CMOS linear regulators. The product has a typical output tolerance of 2.5%, an extremely low dropout voltage of 450mV at 1A load current, VOUT = 5V, and excellent AC performance using ultra low ESR ceramic output capacitors. The low thermal resistance of the LLP, SOT-223 and T0-252 packages allows the full operating current to be used even in high ambient temperature environments. The use of a PMOS power transistor means that no DC base drive current is required to bias it, allowing ground pin current to remain below 100µA regardless of load current, input voltage, or operating temperature.

LP3856-ADJ 3A Fast Response Ultra Low Dropout Linear Regulators is a ultra low dropout linear regulator from Linear Technology. It features ultra low dropout, fast response, low quiescent current, etc. It is suitable for various low voltage microprocessor applications.

The LP3853/LP3856 series of fast ultra low-dropout linear regulators are developed on a CMOS process which allows low quies- cent current operation independent of output load current. This CMOS process also allows the LP3853/LP3856 to op- erate under extremely low dropout conditions.

LP3852/LP3855 1.5A Fast Response Ultra Low Dropout Linear Regulators. These linear regulators operate from a +2.5V to +7.0V input supply and have a wide range of preset output voltage options. They respond very quickly to step changes in load, which makes them suitable for low voltage microprocessor applications.

LP265-LP365 Micropower Programmable Quad Comparator

The LP3470 is a micropower CMOS voltage supervisory circuit designed to monitor power supplies in microprocessor (µP) and other digital systems. It provides maximum adjustability for power-on-reset (POR) and supervisory functions. It is available in the following six standard reset threshold voltage (VRTH) options: 2.63V, 2.93V, 3.08V, 4.00V, 4.38V, and 4.63V. If other voltage options between 2.4V and 5.0V are desired, please contact your National Semiconductor representative. The LP3470 asserts a reset signal whenever the VCC supply voltage falls below a reset threshold. The reset time-out period is adjustable using an external capacitor. Reset remains asserted for an interval (programmed by an external capacitor) after VCC has risen above the threshold voltage. The device is available in the tiny SOT23-5 package.

The LMX2335L/LMX2336L are monolithic, integrated dual frequency synthesizers, including two high frequency prescalers, and are designed for applications requiring two RF phase-lock loops.

The LMX2306/16/26 are three low power frequency synthesizers. They are used to generate a very stable low noise signal for controlling the local oscillator of an RF transceiver. The three products use different pre-dividers, which are 8/9 and 32/33. The working voltage range of the three products is 2.3V to 5.5V, and they have ultra-low current consumption. At 3V, the typical current consumption of LMX2306 is 1.7mA, LMX2316 is 2.5mA, and LMX2326 is 4.0mA.

LMX2324 PLLatinum 2.0 GHz frequency synthesizer for RF personal communications

The LM221 series is a precision preamplifier designed to operate with general purpose operational amplifiers to drastically decrease dc errors, drift, bias current, common mode, and supply rejection are more than a factor of 50 better than standard op amps alone. Furthermore, the added dc gain of the LM221 decreases the closed loop gain error. The LM221 series operates with supply voltages from 3V to 20V and has sufficient supply rejection to operate from unregulated supplies. The operating current is programmable from 5 mA to 200 mA so bias current, offset current, gain, and noise can be optimized for the particular application while still realizing very low drift. Super-gain transistors are used for the input stage so input error currents are lower than conventional amplifiers at the same operating current. Furthermore, the initial offset voltage is easily nulled to zero. The extremely low drift of the LM221 will improve accuracy on almost any precision dc circuit. For example, instrumentation amplifier, strain gauge amplifiers, and thermocouple amplifiers now using chopper amplifiers can be made with the LM221. The full differential input and high common-mode rejection are another advantage over choppers. For applications where low bias current is more important than drift, the operating current can be reduced to low values. High operating currents can be used.

LM2202 is a very high frequency video amplifier system intended for use in high resolution monochrome or RGB color monitor applications. In addition to the wideband video amplifier, the LM2202 contains a gated differential input black level clamp comparator for brightness control, a DC controlled attenuator for contrast control and a DC controlled sub contrast attenuator for drive control. The DC control for the contrast attenuator is pinned out separately to provide a more accurate control system for RGB color monitor applications. All DC controls offer a high input impedance and operate over a 0V to 4V range for easy interface to bus controlled alignment systems. The LM2202 operates from a nominal 12V supply but can be operated with supply voltages down to 8V for applications that require reduced IC package power dissipation characteristics.

The LM119/LM219/LM319 High Speed Dual Comparator is a single monolithic chip that has high precision, high speed, and low input current.