Date: 14/10/2011

High temp grade sync step-down switching regulator LT3690

Linear Technology has announced the high temperature (H-grade) and High Reliability (MP-grade) versions of its synchronous step-down switching regulator LT3690 with efficiency up to 93%, which is suitable for, load dump and cold-crank conditions found in automotive applications. The LT3690's Burst Mode operation requires 70µA of quiescent current, ideal for applications such as automotive or telecom systems, which demand always-on operation and optimum battery life.

Key features of LT3690HUFE & LT3690MPUFE include:

Versions of 36V, 4A Synchronous Monolithic Step-Down Regulators
Wide Input Range: Operation from
3.9V to 36V, Overvoltage Lockout
Protects Circuits Through 60V Transients
4A Continuous Maximum Output Current
Integrated 30mOhm N-Channel Synchronous Switch
70µA IQ at 12VIN to 3.3VOUT
Low Ripple Burst Mode Operation Allows Output Ripple <15mVP-P
Programmable Input Undervoltage Lockout
0.8V Feedback Reference Voltage
Output Voltage 0.8V to 20V
Programmable & Synchronizable Oscillator (170kHz to 1.5MHz)
Soft-Start-up & Output Voltage Tracking
Short-Circuit Robust
Power Good Flag
-55°C to 150°C Temperature Range-MP Grade
-40°C to 150°C Temperature Range-H Grade

Electrical specifications for the H-grade and the MP-grade are identical to the E and I grades. They are ideal for automotive, industrial and military applications, which are subject to high ambient temperatures.

Availability, package and price: Both the LT3690HUFE and the LT3690MPUFE are available in 26-lead 4mm x 6mm QFN packages. Pricing starts at $5.70 and $14.70 each, respectively, for 1,000-piece quantities and are available from stock.

For more information, visit www.linear.com/product/LT3690.