General Description
The RT6263A/B is a simple, easy-to-use, 3A
synchronous step-down DC-DC converter with an input
supply voltage range of 4.5V to 17V. The device
possesses an accurate reference voltage and
integrates low RDS(ON) power MOSFETs to achieve
high efficiency.
The RT6263A/B adopts Advanced Constant On-Time
(ACOT® ) control architecture to provide an ultrafast
transient response with few external components and
to operate in nearly constant switching frequency over
the line, load, and output voltage range. The RT6263A
operates in automatic PSM that maintains high
efficiency during light load operation. The RT6263B
operates in Forced PWM that helps meet tight voltage
regulation accuracy requirements.
The RT6263A/B senses both FETs current for a robust
over-current protection (OCP). The device features
cycle-by-cycle current limit protection to prevent the
device from the catastrophic damage in output short
circuit, over-current or inductor saturation conditions.
The RT6263A/B offers programmable start-up by
connecting a capacitor at external SS pin. The device
also includes input under-voltage lockout, output
under-voltage protection, and over-temperature
protection (OTP) to provide safe and smooth operation
in all operating conditions.

Features
 3A Converter Integrated 66m and 36m FETs
 Input Supply Voltage Range : 4.5V to 17V
 Output Voltage Range : 0.765V to 7V
 Advanced Constant On-Time (ACOT® ) Control
 Ultrafast Transient Response
 Optimized for Low-ESR Ceramic Output
Capacitors
 High Accuracy Feedback Reference Voltage : Typ.
 1%
 Optional for Operation Modes :
 RT6263A : Power Saving Mode (PSM)
 RT6263B : Forced PWM Mode
 Fixed Switching Frequency : 650kHz
 Enable Control and Externally Adjustable
Soft-Start
 Input Under-Voltage Lockout (UVLO)
 Protection Function
 Output Under-Voltage Protection (UVP) with
Hiccup Mode
 High- / Low-side MOSFET OCP and OTP
Function
 Power Good Indication
 RoHS Compliant and Halogen Free