DESCRIPTION

· The RT9709 is an integrated circuit designed to protect low voltage systems from abnormal high voltage inputs up to 28V.
· It monitors input voltage, battery voltage, and charging current to ensure they operate within normal ranges.
· The IC also monitors its own temperature and disables the MOSFET when the chip temperature exceeds 140°C.
· It supports both AC and USB chargers and can turn off the MOSFET within 1us if the input voltage exceeds the OVP threshold.
· The current limit in the MOSFET can be programmed using an external resistor.
· The IC includes a 4-bit binary counter for OCP events, turning off the MOSFET permanently after 16 counts unless the input power is recycled.
· It monitors battery voltage and turns off the MOSFET if the voltage exceeds 4.4V for more than 180us.

FEATURES

· Fully integrated protection circuit for three protection variables.
· User programmable OCP threshold.
· Input OVP response time less than 1us.
· Battery OVP protection.
· Up to 30V over voltage protection.
· High accuracy protection thresholds.
· High immunity to false triggering under transients.
· Warning indication output.
· Enable input.
· Thermally enhanced WDFN package.
· RoHS compliant and halogen free.

APPLICATIONS

· Cellular phones.
· Digital cameras.
· PDAs and smart phones.
· Portable instruments.