LM3224 Datasheet | National Semiconductor

Description The LM3224 is a step-up DC/DC converter with a 0.15Ω (typ.), 2.45A (typ.) internal switch and pin selectable operating frequency. With the ability to convert 3.3V to multiple outputs of 8V, -8V, and 23V, the LM3224 is an ideal part for biasing TFT displays. With the high current switch it is also ideal for driving high current white LEDs for flash applications. The LM3224 can be operated at switching frequencies of 615k Hz and 1.25MHz allowing for easy filtering and low noise. An external pensation pin gives the user flexibility in setting frequency pensation, which makes possible the use of small, low ESR ceramic capacitors at the output. An external soft-start pin allows the user to control the amount of inrush current during start up. The LM3224 is available in a low profile 8-lead MSOP package. Features n n n n n Operating voltage range of 2.7V to 7V 615k Hz/1.25MHz pin selectable frequency operation Over temperature protection Optional soft-start function 8-Lead MSOP package Applications n n n n n n TFT Bias Supplies Handheld Devices Portable Applications GSM/CDMA Phones Digital Cameras White LED Flash/Torch Applications Typical Application Circuit .. © 2004 National Semiconductor Corporation DS200976 .national. . .. 4U. .. Connection Diagram Top View 8-Lead Plastic MSOP NS Package Number MUA08A Ordering Information Order Number LM3224MM-ADJ LM3224MMX-ADJ LM3224MM-ADJ LM3224MMX-ADJ NOPB NOPB Spec. Package Type MSOP-8 MSOP-8 MSOP-8 MSOP-8 NSC Package Drawing MUA08A MUA08A MUA08A MUA08A Supplied As 1000 Units, Tape and Reel 3500 Units, Tape and Reel 1000 Units, Tape and Reel 3500 Units, Tape and Reel Package Top Mark SEKB SEKB SEKB SEKB Pin Description Pin 1 2 3 4 5 6 7 8 .. Name VC FB SHDN GND SW VIN FSLCT SS Output voltage feedback input. Shutdown control input, active low. This pin has an internal pulldown resistor so the default condition is off. The pin must be pulled high to turn on the device. Analog and...