DESCRIPTION

· The RT9709 is an integrated circuit designed to protect low voltage systems from 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, turning off the MOSFET when it exceeds 140°C.
· It supports both AC and USB chargers, turning off the MOSFET within 1us if the input voltage exceeds the OVP threshold.
· The current limit in the MOSFET is programmable via an external resistor, and the IC includes a 4-bit binary counter for OCP events.
· The MOSFET is permanently turned off after 16 OCP events unless the input power is recycled.
· The IC monitors battery voltage, turning off the MOSFET if it exceeds 4.4V for more than 180us, and latches off after 16 over-voltage events.

FEATURES

· Fully integrated protection circuit for three protection variables.
· User programmable OCP threshold.
· Input OVP response in less than 1us.
· Battery OVP with protection up to 30V.
· 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.