GND (Pin 1): Signal Ground. Tie to PGND under the package.
LBO (Pin 2): Open-Collector Output of Low-Battery Comparator.Can sink 100mA. Disabled when device is in shutdown.
SHDN (Pin 3): Shutdown. Pull high to shut down the device. Ground for normal operation.FB/Sense (Pin 4): On 1303 (adjustable) this pin connects to the main comparator C1 input. On LT1303-5 this pin connects to the resistor string that sets output voltage at 5V.
LBI (Pin 5): Low-Battery Comparator Input. When voltage on this pin below 1.24V, LBO is low.VIN (Pin 6): Supply Pin. Must be bypassed with a large value electrolytic to ground. Keep bypass within 0.2" of the device.
SW (Pin 7): Switch Pin. Connect inductor and diode here.Keep layout short and direct to minimize radio frequency
interference.
PGND (Pin 8): Power ground. Tie to signal ground (pin1) under the package. Bypass capacitor from VIN should be tied directly to PGND within 0.2" of the device.
Electroluminescent (EL) panels offer a viable alternative to LED, incandescent, or CCFL backlighting systems in many portable devices. EL panels are thin, rugged, lightweight, and low power; require no diffuser, and emit aesthetically pleasing blue-green light. Capacitive in nature, they typically exhibit about 3000 pF/in2 of panel area and require a low-frequency (50 Hz to 1 kHz) 120-V rms ac drive. These problems can be solved by using a setup that includes an LT1303 micropower switching-regulator IC along with a small surface-mount transformer in a flyback topology. The 400-Hz drive signal can be supplied externally or derived from a simple CMOS 555 circuit. When the drive signal is low, flyback transformer T1 charges the panel until the voltage at point A reaches 240 Vdc. C1 removes the dc component from the panel drive, resulting in +120 Vdc at the panel. When the input drive signal goes high, the LT1303's feedback (FB) pin is pulled high as well, idling the IC and turning on Q1. Q1's collector pulls point A to ground and the panel to -120 Vdc. C2 can be added to limit voltage if the panel is disconnected or open. R1 provides intensity control by varying the output voltage. Intensity also can be modulated by varying the drive-signal frequency.
The LT®1303/LT1303-5 are micropower step-up high efficiency DC/DC converters using Burst ModeTM operation.They are ideal for use in small, low-voltage batteryoperated systems. The LT1303-5 accepts an input voltage between 1.8V and 5V and converts it to a regulated 5V. The LT1303 is an adjustable version that can supply an output voltage up to 25V. Quiescent current is only 120mA from the battery and the shutdown pin further reduces current to 10mA. The low-battery detector provides an opencollector output that goes low when the input voltage drops below a preset level. The on-chip NPN power switch has a low 170mV saturation voltage at a switch current of 1A. The LT1303/LT1303-5 are available in 8-lead PDIP or SO packages, easing board space requirements.
For higher output current, please see the LT1305 or LT1302.
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EL Panel Drivers 2-Cell and 3-Cell to 5V Conversion Palmtop Computers Portable Instruments Bar-Code Scanners PDAs Wireless Systems
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5V at 200mA from a 2V Input Supply Voltage As Low As 1.8V Up to 88% Efficiency 120mA Quiescent Current Low-Battery Detector Low VCESAT Switch: 170mV at 1A Typ Uses Inexpensive Surface Mount Inductors 8-Lead PDIP or SO Package
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VIN Voltage .............................................................. 10V
SW1 Voltage ............................................................ 25V
Sense Voltage (LT1303-5) ....................................... 20V
FB Voltage (LT1303) ................................................ 10V
Shutdown Voltage ................................................... 10V
LBO Voltage ............................................................. 10V
LBI Voltage .............................................................. 10V
Maximum Power Dissipation .............................. 500mW
Operating Temperature Range ................. 0°C to 70°C
Storage Temperature Range ............ 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
Post a Buying Lead
Required Field 
