LM3224MM-ADJ/NOPB

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 615kHz and 1.25MHz allowing for easy filtering and low noise. An external compensation pin gives the user flexibility in setting frequency compensation, 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. The LM3224 utilizes a PWM control scheme to regulate the output voltage over all load conditions. The LM3224 has dedicated protection circuitry running during normal operation to protect the IC. The Thermal Shutdown circuitry turns off the NMOS power device when the die temperature reaches excessive levels. The UVP comparator protects the NMOS power device during supply power startup and shutdown to prevent operation at voltages less than the minimum input voltage. The OVP comparator is used to prevent the output voltage from rising at no loads allowing full PWM operation over all load conditions. The LM3224 also features a shutdown mode decreasing the supply current to 0.1μA (typ.).

Applications

• TFT Bias Supplies
• Handheld Devices
• Portable Applications
• GSM/CDMA Phones
• Digital Cameras
• White LED Flash/Torch Applications

Key features

• Operating voltage range of 2.7V to 7V
• 615kHz/1.25MHz pin selectable frequency operation
• Over temperature protection
• Optional soft-start function
• 8-Lead MSOP package