April 23, 2012 – Linear Technology Korea (CEO Hong Sa-gwak) announced the launch of the LT3988, a 60VIN step-down switching regulator that provides dual 1A outputs. The LT3988 operates within an input voltage range of 4V to 60V and provides overvoltage lockout protection under high transient voltages of approximately 80V, making it ideal for load dump and cold-crank conditions commonly encountered in automotive applications. The LT3988 is driven by two independent input rails or a single input, maximizing design flexibility. The internal 1.3A switch provides continuous output current up to 1A. The switching frequency is user-programmable from 250kHz to 2.5MHz, allowing designers to maximize efficiency while avoiding noise-sensitive frequency bands. With the enhanced thermal performance of the MSOP-16E package and high switching frequency characteristics, this product enables the use of small inductors and capacitors, providing a compact and thermally efficient footprint.
The LT3988 utilizes dual high-efficiency 1.3A switches with integrated boost diode, oscillator, control and logic circuits on a single chip. The catch diode current sense (DA) pin protects the circuit when input voltage becomes excessive (even at high switching frequencies) and additionally provides robust short-circuit protection. Anti-phase switching minimizes both input and output ripple. Special design techniques are employed in the LT3988 to achieve high efficiency across a wide input voltage range, and the current-mode topology provides fast transient response and excellent loop stability. Other features include external synchronization (250kHz to 2.5MHz), internal loop compensation, thermal shutdown and tracking functions.
The LT3988EMSE starts at $2.65 per unit. The industrial temperature grade version, LT3988IMSE, is tested and guaranteed to operate at a junction temperature of -40°C to 125°C. The high-temperature version, LT3988HMSE, is tested and guaranteed to operate at temperatures from -40°C to 150°C, with a price of $4.45 per unit. The stated prices are all based on quantities of 1,000 units, and all versions are currently available for immediate purchase. For detailed product information, refer to www.linear.com/product/LT3988.
Photo caption: Dual 60V Step-Down Converter

Product Features: LT3988

• Wide input range: operates at 4V to 60V, circuit protection at 80V transient voltage with overvoltage lockout function
• Two 1A output switching regulators with integrated internal power switch
• Short-circuit protection
• Adjustable 0.25MHz to 2.5MHz switching frequency, synchronizable across the full range
• Integrated boost diode
• Integrated loop compensation function
• Ripple reduction with anti-phase switching
• Low shutdown IQ (<2μA)
• Small inductor and ceramic capacitor compatible
• Enhanced thermal performance 16-pin MSOP package