Sipex introduces high efficiency, four-channel charge pump LED driver

Dec. 6, 2004
Date Announced: 06 Dec 2004 Sipex Corporation has further expanded its family of LED drivers with the SP7683. This high efficiency charge pump independently regulates up to four white LEDs and is ideal for backlighting color displays in portable applications such as cell phones, digital cameras and PDAs. The SP7683 can generate regulated output current using two distinct operating modes. At high input voltages, it functions as a linear regulator. At low input voltages, it functions as a 1.5X charge pump, boosting input voltage to maintain desired LED forward current. This dual-mode architecture in addition to low shutdown current enables greater efficiency, constant brightness and longer battery life. The SP7683 provides a matched current source of up to 160mA total (40mA per LED) for all channels. The LED current is user programmable by using a single external current set resistor, which sets the current for all LEDs. Brightness can be adjusted either by varying the value of the set resistor or by employing a PWM dimming scheme. Since the part is designed with integrated current sense circuitry, there is no external current sensing resistor required. SP7683 Key Features (typical):-- 2.7V to 5.5V input voltage range -- Independently regulates up to 4 LEDs -- 1X and 1.5X mode charge pump -- High efficiency operation -- 1.2MHz switching frequency -- PWM dimming control -- Low 0.5uA shutdown current -- Built in soft-start -- Thermal shutdown protection -- QFN (4mm x 4mm) package Pricing and Availability The SP7683 samples are available now. The part is rated over the industrial temperature range of -40 degrees C to +85 degrees C and is housed in a 4mm x 4mm QFN package. Pricing for the SP7683 begins at $1.55 in 1,000 piece quantities. Datasheets and additional information on this family and other Sipex product offerings may be found on the company web site at

Sharon Guerrand Phone: 408-934-7500 Fax: 408-935-7600


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