Semtech Introduces New High Efficiency PWM Controller to Support Multiple System Supply Voltages; Device Simplifies Design and Reduces Total System Cost in Notebook Computers.Business Editors & High-Tech Writers CAMARILLO, Calif.--(BUSINESS WIRE)--Oct. 24, 2002 Semtech Corp. (Nasdaq: SMTC SMTC Southern Maine Technical College SMTC Science/Mathematics/Technology Center (Central Michigan University) SMTC Saluda Mountain Telephone Company (Knoxville, Tennessee) SMTC Short-To-Medium Term Control ), a leading supplier of analog and mixed-signal semiconductors for communications, portable devices, computers, and industrial equipment, today announced availability of the SC1403, a multi-output PWM (Pulse Width Modulation) A modulation technique that generates variable-width pulses to represent the amplitude of an analog input signal. Like its fixed-width pulse density modulation (PDM) cousin, the output switching transistor is on more of the time for a controller employing Semtech's proprietary Virtual Current Sense(TM) technology. This product provides important features that simplify design and reduce total system cost, while also delivering the high efficiency required by today's battery-powered notebook PC applications. The SC1403 is designed to operate from a 6V to 30V input supply, making it ideal for operation from either an AC adapter Same as power adapter. or battery pack. The SC1403 implements two high efficiency, synchronous Refers to events that are synchronized, or coordinated, in time. For example, the interval between transmitting A and B is the same as between B and C, and completing the current operation before the next one is started are considered synchronous operations. Contrast with asynchronous. power supply controllers preset preset Cardiac pacing A parameter of a pacemaker that is programmed permanently when manufactured to generate the 3.3V and 5V supply voltages typically required in a notebook PC. These outputs can also be adjusted between 2.5V and 5.5V. Two key features are incorporated into the SC1403 that help reduce system cost. The switching power supply Switch´ing power supply n. 1. a device used as part of an electronic device, which transforms electrical current from an AC line circuit to DC for use in electronic devices, and which can use either 110 volt or 220 volt AC line curent. controllers operates 180-degrees out-of-phase, providing ripple cancellation at the input supply. This enables designers to employ as little as one-half of the input capacitance capacitance, in electricity, capability of a body, system, circuit, or device for storing electric charge. Capacitance is expressed as the ratio of stored charge in coulombs to the impressed potential difference in volts. required by competitive products that do not offer out-of-phase operation. Also, this device offers external compensation capability for each switcher. Such capability allows a designer to optimize the output filter for voltage ripple and transient response In electrical engineering and Mechanical Engineering, a transient response or natural response is the response of a system to a change from equilibrium. Specifically, transient response in Mechanical Engineering is the portion of the response that approaches zero after a while guaranteeing stable operation. Other products on the market enforce output capacitor-ESR value constraints to provide stability. With external compensation, there are no such restrictions; designers have full flexibility to optimize their designs for performance, cost, or both. A significant benefit of Semtech's Virtual Current Sense technology is its ability to enhance control loop stability. This enables fixed frequency operation over a wide range of output filter components and virtually eliminates the jitter A flicker or fluctuation in a transmission signal or display image. The term is used in several ways, but it always refers to some offset of time and space from the norm. For example, in a network transmission, jitter would be a bit arriving either ahead or behind a standard clock cycle seen in most fixed-frequency PWMs. Virtual Current Sense, combined with external compensation capability, reduces development risk by removing layout sensitivity from the design. "The SC1403 provides system and power-supply designers with an unrivaled combination of options and performance from a PWM controller designed for mobile applications," stated Eddie Yeow, Director of Portable Power Management for Semtech. "We are proud to offer products that not only help customers reduce development risks and system costs but maximize their productivity and time-to-market as well." Several features are offered to maximize battery life in notebook PCs, including: -- Very low quiescent power consumption -- 6mW (typ). In stand-by mode, quiescent current is reduced to 180uA (typ). In shutdown, the total supply current is 4uA (typ). -- Selectable power-save mode. When the load current falls below an externally programmable threshold, the switcher operates as a hysteretic controller in discontinuous mode, eliminating unnecessary switching cycles and therefore improving light-load efficiency. -- Greater than 1A typical gate drive for fast MOSFET switching, reducing switching losses. The drivers also support use of the latest low RDS (on) MOSFETs optimized for mobile applications, helping to reduce conduction losses. Other features include excellent line (0.05%/V) and load (-0.4%) regulation; over-current, over-voltage and over-temperature protection; under-voltage lockout lockout, intentional closing up of a company, factory, or shop by an employer to prevent employees from working during a strike or labor dispute. The term lockout ; and a 5V linear regulator In electronics, a linear regulator is a voltage regulator based on an active device (such as a bipolar junction transistor, field effect transistor or vacuum tube) operating in its "linear region" (in contrast, a switching regulator is based on a transistor forced to act as an capable of delivering up to 50mA in standby mode A sleep mode in a portable computer that provides an almost immediate resumption of operation when turned back on. In standby mode, the hard disk and display are turned off, and the CPU is throttled down to its lowest-power state. . The SC1403 is rated for operation over the industrial temperature range of -40 to +85 degrees Celsius. Pricing and Availability The SC1403 multi-output PWM controller, supplied in TSSOP-28 packaging, is in volume production. Pricing and evaluation samples are available through Semtech's network of direct sales representatives and distributors or by contacting sales@semtech.com. About Semtech Semtech Corporation is a leading supplier of high-quality analog and mixed-signal ICs for power management, over-voltage and transient protection, human interface devices & system management, test & measurement applications, and advanced communications. Publicly traded since 1967, Semtech is listed on the NASDAQ National Market under the symbol SMTC. For more information, contact Semtech Corp. at 200 Flynn Road, Camarillo, CA. 93012; phone (805) 498-2111; email to info@semtech.com; or visit its Web site at www.semtech.com. Note to Editors: Semtech, the Semtech logo, and Virtual Current Sense are either trademarks or registered marks of Semtech Corporation. A "u" represents the micron micron: see micrometer. One micrometer, which is one millionth of a meter or approximately 1/25,000 of an inch. The tiny elements that make up a transistor on a chip are measured in micrometers and nanometers. See process technology. symbol when used as part of "uA" throughout this release... in "(reduced to 180uA (typ))", "(supply current is 4uA (typ))". |
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