L6726A
Device description
4
Device description
L6726A is a single-phase PWM controller with embedded high-current drivers that provides
complete control logic and protections to realize in an easy and simple way a general DC-
DC step-down converter. Designed to drive N-channel MOSFETs in a synchronous buck
topology, with its high level of integration this 8-pin device allows reducing cost and size of
the power supply solution.
L6726A is designed to operate from a 5 V or 12 V supply bus. Thanks to the high precision
0.8V internal reference, the output voltage can be precisely regulated to as low as 0.8 V with
±1% accuracy over line and temperature variations (between 0 °C and +70 °C). The
switching frequency is internally set to 270 kHz.
This device provides a simple control loop with externally compensated transconductance
error-amplifier and programmable soft start. Low-side-less feature allows the device to
perform soft-start over pre-charged output avoiding negative spikes at the load side.
In order to avoid load damages, L6726A provides programmable threshold over current
protection. Output current is monitored across low-side MOSFET R
dsON
, saving the use of
expensive and space-consuming sense resistor. L6726A also features FB disconnection
protection, preventing dangerous uncontrolled output voltages in case of floating FB pin.
Doc ID 12754 Rev 4
9/35
STMICROELECTRONICS [ STMICROELECTRONICS ]
