STR-X6750 Datasheet | Sanken

Product Information STR-X6700 Series Off-Line Quasi-Resonant Switching Regulators Introduction The STR-X6700 series integrates a quasi-resonant control IC and a MOSFET with avalanche guarantee. In normal operation, the device provides high efficiency and low EMI noise with bottom-skip quasi-resonant operation during light output loads. Low power consumption is also achieved by Auto-standby mode (not available in the STR-X6729, STR-X6759N, or STR-X6768N) or manual standby mode (external trigger). The device is supplied in a seven-pin fully-molded TO-3Pstyle package, which is suitable for downsizing and standardizing of an SMPS by reducing external ponent count and simplifying circuit design. Features and benefits include the following: - Auto standby mode (burst oscillation) or manual standby mode (UVLO intermittent oscillation) in the standby mode. - In addition to the standard quasi-resonant operation, a bottom-skip mode is available for increased efficiency from light to medium load. - Soft-start operation at start-up. - Reduced switching noise (pared to conventional PWM hard-switching solution) with a step-drive function. - Built-in avalanche-energy-guaranteed power MOSFET (to simplify surge-absorption circuit; no VDSS derating is required). - Overcurrent protection (OCP), overvoltage protection (OVP), overload protection (OLP), and maximum On-time control circuits are incorporated; OVP and OLP go into a latched mode. The product lineup for the STR-X6700 series provides the options shown in table 1. Contents Introduction Pin functional descriptions Operation description Transformer parameters General considerations Design considerations Package dimensions, TO-3P Worldwide Contacts 1 2 6 10 11 13 14 19 LF1901 LF1902 LF1905 Figure 1. STR-X6700 series packages are fully molded TO-3P package types: LF1901 (STR-X6737 and STR-X6769), LF1902 (STR-X6729 and STR-X6768N), and LF1905 (STR-X6757 and STR-X6759N). Table 1. Product Line-up Type #...