4A 30V 500kHz synchronous step-down DC/DC converter

ELM613xDC is a fully integrated high efficiency synchronous step-down converter which requires minimum number of external components. It offers very compact solution with up to 4A continuous output current over a wide input range. ELM613xDC employs proprietary Constant On-Time (COT) control scheme providing superior transient response and maintaining constant switching frequency under the continuous conduction mode operation. The internal ramp compensation network allows stable operation with ultra-low equivalent series resistance (ESR) output ceramic capacitors without using external compensation network. An error amplifier in the control loop provides excellent line and load regulation. ELM613xDC integrates extensive protection functions include: UVLO, OCP and thermal shutdown. Input under- voltage lockout is internally set as 3.8V.
The unique ultrasonic pulse-skipping mode (ELM613UDC) maintains the switching frequency above 25kHz, which eliminates noise in audio applications. Other features include pulse skipping mode (ELM613NDC), which maximizes efficiency in light-load applications, and forced PWM mode(ELM613ADC) which operates in constant frequency PWM mode regardless of load current.

Stable operation with output low ESR ceramic capacitors
Externally adjustable built-in soft start (Typ.2ms)
Fast PWM Constant On Time (COT) control scheme
with superior transient performance
Accurate EN threshold for the external programmable Vin UVLO
Low quiescent current
Thermal shutdown with auto recovery
Hiccup mode 8 times then latch-off over current protection
Input voltage range4.0V to 30.0V
Feedback voltage accuracy0.8V±2%
Continuous output current Max.4A(5A Peak)
Duty cycle
(low dropout operation)
Switching frequencyTyp.500kHz
2 Types of light load mode and a forced PWM mode control schemesELM613UDC:
Ultrasonic pulse skip mode (25kHz min)
Pulse skip mode
Forced PWM mode
Integrated high side and low side switches40mΩ/40mΩ
(with Exposed Pad)
Show datasheet
Laptop computer
Tablet PC
Networking systems
Personal video recorders
Flat panel television and monitors
Distributed power systems

Recommend Operating Conditions

Supply voltageVin+4.0 to +30.0V
Output voltageVout0.8 to VinV
Operating temperatureTop-40 to +125°C

Absolute Maximum Ratings

VIN supply voltageVin+36V
EN to GNDVen+36V
SW to GNDVsw-0.3 to Vin+0.3V
PGND to GNDVpgnd-0.3 to +0.3V
BST to SWVbst-0.3 to +6.0V
All other pins to GNDVall-0.3 to +6.0V
Junction temperatureTj+150°C
Thermal resistanceθja51°C/W
Power dissipationPd2.45W
Storage temperature rangeTstg-65 to +150°C

Block diagram