LTC3809EMSE#PBF - Low EMI, No RSENSE Step-Down DC/DC Controller

The LTC3809EMSE#PBF is a high-performance step-down switching regulator DC/DC controller from Linear Technology that delivers excellent power efficiency and low electromagnetic interference (EMI) emissions. This product is designed to operate over a wide input voltage range from 2.75V to 9.8V, making it suitable for a variety of applications including industrial, automotive, and telecommunications systems.

One of the standout features of the LTC3809EMSE#PBF is its patented controlled on-time, valley current mode control algorithm which allows for fast transient response, excellent loop stability, and very low output voltage ripple. This unique control scheme does not require the use of a sense resistor (RSENSE), which simplifies the design and reduces system cost and power loss.

The device is housed in a compact 10-lead MSOP package with an exposed pad for enhanced thermal performance. Its operating frequency is user-programmable from 300kHz to 4MHz, which allows the use of small surface mount inductors and capacitors, saving space and cost on the PCB. Additionally, the high-frequency capability enables the design of converters with very low output ripple and fast transient response.

The LTC3809EMSE#PBF also features a range of protective measures to ensure the longevity and reliability of the end application. This includes overvoltage protection, undervoltage lockout, and a foldback current limit that reduces the output current to prevent excessive power dissipation during overload conditions. Furthermore, the device offers a power good output signal, which provides a system-ready signal to downstream circuits once the output voltage is within regulation.

In summary, the LTC3809EMSE#PBF is a versatile and efficient solution for those in need of a low EMI, high-performance DC/DC controller. Its no RSENSE design, flexible operating frequency, and comprehensive protection features make it an ideal choice for a wide range of power conversion applications.