60V, synchronous buck-boost controller regulates up to 250W
Its output voltage can be set from 0V to 60V, for use as a voltage regulator or battery/supercapacitor charger. The LT3790’s internal 4-switch buck-boost controller operates from input voltages above, below or equal to the output voltage, for applications such as automotive, where the input voltage can vary dramatically during stop/start, cold crank and load dump scenarios. Transitions between buck, pass-through and boost operating modes are seamless, offering a well regulated output in spite of wide variations of supply voltage. The LT3790’s design has three control loops to monitor input current, output current and output voltage.
The LT3790 uses four external switching MOSFETs and can deliver up to 250W of continuous output power with efficiencies up to 98.5%. Output current accuracy of ±6% ensures precise current regulation while ±2% output voltage accuracy offers a precise output voltage, making it suitable for charging applications. Multiple LT3790s can be paralleled for higher power requirements. Its switching frequency can be programmed between 200 kHz and 700 kHz or synchronised to an external clock. Additional features include output disconnect, input and output current monitors, a C/10 charge termination and integrated fault protection.
The LT3790EFE is available in a 38-lead thermally enhanced TSSOP package, priced starting at $4.75 (1,000); there are extended temperature and high temperature versions.
Linear Technology; www.linear.com/product/LT3790
next page; full feature list
Summary of Features: LT3790
4-switch single inductor architecture allows VIN above, below or equal to VOUT
Synchronous switching: Up to 98.5% Efficiency
Wide VIN range: 4.7V to 60V
±2% output voltage accuracy:
1.2V ≤ VOUT < 60V
±6% output current accuracy:
0V ≤ VOUT < 60V
Input & output current regulation with current monitor outputs
No top FET refresh in buck or boost
VOUT disconnected from VIN during shutdown
C/10 charge termination & output shorted flags
Capable of up to 250W per IC
Easy parallel capability to extend output power
38-Lead TSSOP with Exposed Pad