Step-down regulator kan operere med indgangspændinger fra 4V til 150V
Linear Technology lancerer 150V input 'kapabel' 100mA synkron step-down regulator, der opererer med en 'quiescent' strøm på kun 12µA (in english).
Modern automotive, industrial and telecom power management ICs continue to require higher performance. As the power requirements for these applications continues to grow, the available space for power conversion solutions continually shrinks requiring even higher power densities.
If large components, such as transient surge suppressors can be eliminated, it further reduces the design complexity, size and cost of these solutions. Additionally, the required electrical performance criterion of these switching regulators becomes more demanding.
For example, a commercial vehicle (truck) application running from a 24V battery bus requires a well regulated output voltage such as 3.3V, even as the input voltage can swing from under 6V in a cold crank or stop/start scenario up to 100V in a load dump scenario.
Similarly, high efficiency is of paramount importance as it minimizes thermal design considerations while also maximizing battery run time in hybrids and electric vehicles. For applications such as security, navigation, safety and environmental control which are often required to be always on, minimal quiescent current is also critical so as not to drain the battery when the vehicle is parked for long periods of time.
Many battery powered industrial applications share this requirement for minimal quiescent current. Finally very robust short-circuit and high input voltage capability ensures overall system reliability.
A new direction
Linear Technology continues to grow its family of high voltage step-down regulators which specifically address all of the above requirements. The LTC3639 is the first synchronous high voltage step-down regulator that has an input voltage range of 4V to 150V which eliminates the requirement for transient surge suppressors. It can deliver up to 100mA of continuous output current to voltages as low as 0.8V.
Its internal synchronous rectification delivers efficiencies as high as 95% which eliminates any requirements for heat sinks while its BurstMode operation requires only 12uA of quiescent current reducing the battery drain associated with always on systems.
The LTC3639 offers low dropout, 100% duty cycle operation and deliver outputs from 0.8V to VIN. Furthermore, output current can be programmed from 10mA to 100mA as required by the individual applications to minimize the size of external components.
The LTC3639 can be programmed to deliver 1.8V, 3.3V and 5V fixed outputs or can set between 0.8V and VIN with a resistor divider. The combination of a MSOP package and only three external components offers a very compact solution footprint for high voltage applications. The LTC3639 delivers a very robust step-down regulator solution which provides improved performance in all key areas including high input voltage capability, efficiency, low quiescent current, size and ease of design.
