AMS1072 Datasheet, PDF (1/6 Pages) Advanced Monolithic Systems Ltd – 2.5V to 8V Input Voltage Range

DESCRIPTION
The AMS1072 is a step-up converter designed for
driving up to 39 white LEDs (13 strings of 3 LEDs
each) from a 5V system rail. The AMS1072 uses a
current mode, fixed frequency architecture to
regulate the LED current, which is measured
through an external current sense resistor. Its low
104mV feedback voltage reduces power loss and
improves efficiency. The OV pin monitors the
output voltage and turns off the converter if an
over-voltage condition is present due to an open
circuit condition.
The AMS1072 includes under-voltage lockout,
current limiting and thermal overload protection
preventing damage in the event of an output
overload.
The AMS1072 is available in small 6-pin SOT23-6
packages.
AMS1072
FEATURES
• 2.5V to 8V Input Voltage Range
• On Board Power MOSFET
• Drives up to 39 White LEDs at 5V Input
• Up to 92% Efficiency
• 1.3MHz Fixed Switching Frequency
• Open Load Shutdown
• Low 104mV Feedback Voltage
• Soft-Start/PWM Dimming
• UVLO, Thermal Shutdown
• Internal 1.3A Current Limit
• Available in SOT23-6 Packages
APPLICATIONS
• Cell Phones
• Handheld Computers and PDAs
• Digital Still Cameras
• Small LCD Displays
TYPICAL APPLICATION
V_IN
4V - 6V
IN
SW
EN
EN _AMS1072 OV
GND
FB
13 Strings
1
Advanced Monolithic Systems http://www.ams-semitech.com