MIC2111 DC/DC multi-mode controller
Micrel, an industry leader in high performance analog and high-speed mixed signal, LAN, and timing and communications solutions, released the MIC2111 DC/DC multi-mode controller, capable of operating in a valley current mode or a voltage mode configuration. This controller provides the necessary PWM signal to interface with industry standard DrMOS. It also interfaces with fully discrete power stages to deliver a high current, low voltage solution to high performance power demanding core rails in the server, communication, and networking markets.
"The MIC2111 is Micrel's first multi-mode controller capable of operating in either a valley current or voltage mode configuration. This device offers design flexibility to optimize for a specific power requirement while minimizing the need to use different controllers, thus eliminating the component qualification process and simplifying inventory management," noted Brian Hedayati, vice president of marketing for high performance linear and power solutions at Micrel. "Moreover, the MIC2111 addresses the design challenge of delivering high power to low voltage core power rails in a constrained space."
In a valley current mode configuration, the MIC2111 allows high frequency operation (up to 2MHz) even under low duty cycle conditions. This resolves a common challenge often present when powering high current, low-voltage core power rails associated with FPGAs, ASICs, and processors from a 12V bus supply. The higher frequency enables a wider operating bandwidth, thereby improving the load transient response while reducing the amount of output capacitance and the size of the inductor. As a benefit, board space and cost are minimized. The same device can also be configured in a voltage mode operation, providing for even better immunity in noise sensitive applications.
To improve performance, the MIC2111 uses a differential DCR current sense for an accurate current limit as well as remote sensing that improves output voltage accuracy; a critical requirement for low voltage core rails in high current applications.
This device offers a host of additional features to provide unique flexibility and protection. The MIC2111 offers overcurrent, over and under voltage protection and is designed to safely start up into a pre-biased output. For additional robustness, this solution includes Micrel's proprietary bi-directional single wire fault pin to ensure that the controller and power stage are operating properly. The switching frequency, output voltage, thermal limit, and soft-start time can all be adjusted externally to meet design requirements. Other factory trimmed optional features include a power on delay and soft-stop operation. The MIC2111 in available in a small 3mm x 3mm TQFN package and operates from -40 ºC to +125 ºC.
The MIC2111 will be available in production and volume quantities starting in the second quarter of 2014 with 1,000 quantities pricing starting at $0.95.
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