Step-Down DC/DC Converters

The AT8028 is a high-efficiency, DC to DC step-down switching regulators, capable of delivering up to 1.5A of output current. The device operates from an input voltage range of 2.6V to 5.5V and provides an output voltage from 0.6V to VIN. Working at a fixed frequency of 2MHz allows the use of small external components, such as ceramic input and output caps, as well as small inductors, while still providing low output ripples. This low noise output along with its excellent efficiency achieved by the internal synchronous rectifier, making AT8028 an ideal replacement for large power consuming linear regulators. Internal soft-start control circuitry reduces inrush current. Short-circuit and thermal shutdown protection improves design reliability. The AT8028 is available in SOT23-5 package.

The AT3408 is a high-efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. The device is available in an adjustable version. Supply current with no load is 40uA and drops to <1uA in shutdown. The 2.5V to 5.5V input voltage range makes the AT3408 ideally suited for single Li-Ion battery powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems. PWM/PFM mode operation provides very low output ripple voltage for noise sensitive applications.

Switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. Low output voltages are easily supported with the 0.6V feedback reference voltage.

The AT3408 is offered in a low profile (1mm) 5-pin, thin SOT package, and is available in an adjustable version.

AT9342 is a high-frequency (1.8MHz) buck-type switch regulator with internal integration of high-side highvoltage power MOSFET. It offers a maximum efficient output of 0.6A for a single channel, achieving rapid loop response through current mode control. A wide input voltage range (4.2V to 40V) enables various applications for buck-type power conversion. The low quiescent current is suitable for batterypowered scenarios. Under light load conditions, efficiency within a wide load range is achieved by reducing switch frequency to minimize losses in both the switch and gate driver. Frequency folding technology helps prevent uncontrolled inductor current during startup. Thermal shutdown ensures reliable and fault-tolerant operation. The AT9342 is packaged in an SOT23-6L package.

The ATDC1934 is a wide input range, high-efficiency, and high frequency DC-to-DC step-down switching regulator, capable of delivering up to 0.7A of output current. With a fixed switching frequency of 660kHz, this current mode PWM controlled converter allows the use of small external components, such as ceramic input and output caps, as well as small inductors. ATI1934 also employs a proprietary control scheme that switches the device into a power save mode during light load, thereby extending the range of high efficiency operation. An OVP function protects the IC itself and its downstream system against input voltage surges. With this OVP function, the IC can stand off input voltage as high as 42V, making it an ideal solution for industrial applications such as smart meters as well as automotive applications.

Input Voltage Range: 4V to 38V
Output Voltage Adjustable Range: 0.8V ~ 0.9V_IN
Output Current up to 700mA
Efficiency up to 95%
750KHz Switching Frequency

The ATDC1934 is a wide input range, high-efficiency, and high frequency DC-to-DC step-down switching regulator. It is powered by a DC voltage between 4V to 38V and output current can go up to 0.7A, with a fixed switching frequency of 660kHz. This evaluation board, ATDC1934EV1, is designed for evaluating the step-down DC/DC converter ATDC1934 conveniently. It is recommended to read this application note with the converter datasheet which provides more detail information about the specifications and application guidance for the converter.

The ATDC2934 is a current mode PWM step-down DC/DC converter with a 0.9Ω Internal Power MOSFET. With its wide input range of 5V to 42V, the ATDC2934 can regulate a wide variety of power sources. The output voltage of the ATDC2934 can be down to 0.8V, and the output current can be up to 600mA. The current mode control provides fast transient response and cycle-by-cycle over current protection. The shutdown current is 0.6μA typical. Adjustable soft start prevents inrush current at turn on. The ATDC2934 features an over temperature shutdown protection.

Input Voltage Range: 5V to 42V
Output Voltage Adjustable Range: 0.8V ~ 0.9V_IN
Output Current up to 600mA
Efficiency up to 93%
1.2MHz Switching Frequency

This evaluation board, ATDC2934EV1, is designed forevaluating the step-down DC/DC converter ATDC2934conveniently. It is recommended to read this applicationnote with the converter datasheet which provides moredetail information about the specifications andapplication guidance for the converter.

The ATI2202 is a 340 kHz fixed frequency PWM synchronous step-down DC/DC converter. The ATI2202 is operated from 4.75V to 18V, the generated output is adjustable from 0.923V to 0.9V_VPS, and the output current can be up to 2A.

Input Voltage Range: 4.75V ~ 18V
Output Voltage Adjustable Range: 0.923V ~ 0.9V_VPS
Output Current up to 2A
Efficiency up to 93%
Programmable Soft Start
Over Current Protection
Over Temperature Protection
RoHS Compliant and 100% Lead (Pb) Free
Fixed Frequency: 340 kHz

ATI2202 has an evaluation board, ATI2202EV1. It has a wide supply range from 4.75V to 18V and can output up to 2A current continuously. It features a synchronous rectification with integrated high and low side power MOSFETs to achieve high efficiency.

ESD safe
Up to 2A output current with 95% efficiency
Wide Input Voltage Range: 4.75V~18V
Wide Adjustable output: 0.923V~0.9V_VPS
Monolithic synchronous buck
Fixed 340kHz frequency
Programmable soft-start on enable control
Overheat, overcurrent and under-voltage protections
RoHS Compliant and 100% Lead (Pb) Free
User friendly layout design for easy measurements

The ATI2301 is a step-down current-mode, DC-DC converter. At heavy load, it works at the constant frequency PWM mode which has good stability and transient response. To ensure the longest battery life under light load in portable applications, the ATI2301 features a power-saving pulse-skipping modulation (PSM) mode, which reduces quiescent current to save power.

High Efficiency: up to 96%
Internal Synchronous Rectifier
High Switching Frequency: 1.5MHz
Under-Voltage Lockout
Soft Start
Short Circuit Protection

The ATI2305 is a 1.5MHz switching frequency step-down current-mode, DC-DC converter. With excellent stability and transient response, the constant-frequency PWM control works well at heavy load.

Efficiency up to 96%
Only 40μA (TYP.) Quiescent Current
Output Current up to 1A
Internal Synchronous Rectifier
Switching Frequency: 1.5MHz
Under-Voltage Lockout
Soft Start
Short Circuit Protection
Thermal Shutdown
5-pin Small SOT23-5, DFN2X2 6-Pin and QFN3X3 16-Pin Package
Pb-Free Package