Wide VIN Range Flyback Controllers Feature 150°C Maximum Junction Temperature
Linear Technology Corporation announces the H-Grade version of the LTC3805/-5 current mode programmable frequency flyback controllers. These devices contain all the features necessary to design high efficiency single-ended isolated and non-isolated flyback converters for telecom, datacom, Power-over-Ethernet (PoE), automotive and general housekeeping power supplies. With its ultralow 40µA start-up current, the LTC3805/-5 allows the use of a high-value input resistor and a low-value capacitor for low power dissipation and quick power supply start-up. The LTC3805H-5 differs from the LTC3805H with its lower turn-on voltage of 4.5V instead of 8.4V.
These parts are ideal for wide input voltage range applications, enabling users to have one power supply for both 48V (36V-75V) and 24V (18V-36V) nominal input systems. The operating frequency is selectable from 70kHz to 700kHz by one external resistor or for noise-sensitive requirements the device can be synchronized to an external clock over the same range. With a standby quiescent current of only 360uA, the LTC3805/-5 is an excellent choice for automotive applications.
The H-Grade products are tested and guaranteed to a junction temperature of +150°C, compared to the E and I Grade versions, which are specified for +85°C and +125°C maximum operating temperatures, respectively. The LTC3805 H-Grade version is ideal for automotive and industrial applications, which are subjected to high ambient temperatures.
Both the LTC3805H and LTC3805H-5 are available from stock in the thermally enhanced MSOP-10 package. Pricing starts at $1.76 each for 1,000 piece quantities. For more information, visit www.linear.com.
Summary of Features: LTC3805H/-5
- Start up Current of 40µA
- VIN and VOUT Limited Only by External Components
- Programmable Turn-On Voltage
- Adjustable Slope Compensation
- Programmable Soft-Start
- Current Mode Control
- 70kHz to 700kHz Programmable Constant Frequency Operation
- Synchronizable up to 700kHz
- Thermally Enhanced MSOP-10 Package
150°C Operating Temperature Flyback
Editor's Contact Information
- Doug Dickinson