An LED driver that drives two LEDs for a camera flash in a portable multimedia device. The LM3553 driver is part of National's PowerWise family of energy-efficient chips that drive one or two LEDs in series, such as mobile phones, PDAs, smart phones, portable scanners, and medical strobes.
National's LM3553 flash LED driver is a fixed-frequency step-up DC/DC converter with two stable current sinks that can deliver up to 1.2A of load current from a single lithium battery. With adjustable overvoltage protection, the chip can drive two serial high current LEDs to further increase the brightness/power ratio of the device. The LM3553 chip features a high-power flash mode to ensure that the camera has enough light to shoot stills, and a low-power flashlight mode to allow enough light when shooting video clips. In addition, the chip also has 128 flash current levels and 16 flash timing periods. System designers can set the appropriate current level and timing for individual applications through an I2C-compatible interface. The LM3553 also has a built-in timeout protection circuit to protect the flash LED from damage during faulty operation.
National's LM3553 flash LED driver can increase the output light brightness of low-power systems to more than 90%, so it is classified as National Semiconductor's PowerWise energy-efficient chip series.
National Semiconductor LM3553 LED Driver Specifications and Features National Semiconductor's LM3553 chip's switching current limit can be flexibly adjusted as needed to facilitate the system to use small inductors with low saturation current. The chip can provide 5V power for LED backlights and audio amplifiers in voltage mode. The chip is set to either high power flash mode or low power flash mode via internal registers or FEN and TX pins to drive one or more high current LEDs. The TX input forces the flash pulse mode to a low current flashlight mode, allowing the flash pulses to be synchronized with RF power amplifier applications or other high current operating modes. Built-in general purpose input/output pins provide hardware support for the system. In the event of a system failure, the hardware reset pin will fully control the chip. In addition, the chip's internal soft-start feature prevents large inrush currents during startup and fast switching frequencies, allowing the product to be designed with smaller external components.
The LM3553 is available in a 12-pin LLP package.
Price and availability
The LM3553 is priced at $1.20 in 1,000-unit quantities and is available in volume.
National's LM3553 flash LED driver is a fixed-frequency step-up DC/DC converter with two stable current sinks that can deliver up to 1.2A of load current from a single lithium battery. With adjustable overvoltage protection, the chip can drive two serial high current LEDs to further increase the brightness/power ratio of the device. The LM3553 chip features a high-power flash mode to ensure that the camera has enough light to shoot stills, and a low-power flashlight mode to allow enough light when shooting video clips. In addition, the chip also has 128 flash current levels and 16 flash timing periods. System designers can set the appropriate current level and timing for individual applications through an I2C-compatible interface. The LM3553 also has a built-in timeout protection circuit to protect the flash LED from damage during faulty operation.
National's LM3553 flash LED driver can increase the output light brightness of low-power systems to more than 90%, so it is classified as National Semiconductor's PowerWise energy-efficient chip series.
National Semiconductor LM3553 LED Driver Specifications and Features National Semiconductor's LM3553 chip's switching current limit can be flexibly adjusted as needed to facilitate the system to use small inductors with low saturation current. The chip can provide 5V power for LED backlights and audio amplifiers in voltage mode. The chip is set to either high power flash mode or low power flash mode via internal registers or FEN and TX pins to drive one or more high current LEDs. The TX input forces the flash pulse mode to a low current flashlight mode, allowing the flash pulses to be synchronized with RF power amplifier applications or other high current operating modes. Built-in general purpose input/output pins provide hardware support for the system. In the event of a system failure, the hardware reset pin will fully control the chip. In addition, the chip's internal soft-start feature prevents large inrush currents during startup and fast switching frequencies, allowing the product to be designed with smaller external components.
The LM3553 is available in a 12-pin LLP package.
Price and availability
The LM3553 is priced at $1.20 in 1,000-unit quantities and is available in volume.
Car Wireless Charger,Wireless Car Charger,Magesafe Car Charger,Usb Car Charger
Comcn Electronics Limited , https://www.comcnspeaker.com