- Achieves 93% efficiency at 2MHz
- Operates from 3.0V ~ 42V input

October 28, 2014 – Linear Technology Korea (CEO Hong Sa-kwak, www.linear.com) announced the launch of the LT8609, a 2A, 42V input synchronous step-down switching regulator. The proprietary synchronous rectification topology delivers 93% efficiency, and with switching operation at 2MHz, designers can avoid frequencies critically susceptible to noise like AM radio, while providing a highly compact solution footprint. Burst Mode® operation maintains quiescent current below 2.5µA under no-load standby conditions, making it ideal for always-on systems. The LT8609's 3.0V ~ 42V input voltage range is ideal for automotive applications. Automotive applications require regulation at cold crank and start/stop conditions at minimum input voltages as low as 3.0V, and must tolerate load dump transients exceeding 40V. The integrated 3.5A switch can deliver a continuous output current up to 2A with a peak load current of 3A.

The LT8609 maintains a minimum dropout voltage of only 200mV (at 1A) under all conditions. This enables excellent performance in scenarios such as automotive cold crank. Spread spectrum frequency modulation and special design techniques provide low EMI operation and minimize noise concerns in automotive and industrial environments. Furthermore, the fast minimum on-time of only 45ns enables constant frequency switching at 2MHz from 16V input to 1.5V output. The LT8609's thermally enhanced 10-pin MSOP package and high switching frequency keep external inductors and capacitors small, providing a compact and thermally efficient footprint.

The LT8609 integrates the essential boost diode, oscillator, control and logic circuits on a single die, utilizing integrated high-efficiency top and bottom power switches. Low ripple Burst Mode operation maintains output ripple below 10mVPK-PK while maintaining high efficiency at low output currents. Proprietary design techniques and new high-speed processes achieve high efficiency across a wide input voltage range. The LT8609's current mode topology enables fast transient response and excellent loop stability. Additional features include internal compensation, power good flag, output soft start/tracking and thermal shutdown protection.

The LT8609EMSE is supplied in a thermally enhanced MSOP-10 package at $2.50 per unit. The industrial temperature version, LT8609IMSE, is tested and guaranteed to operate at junction temperatures from –40°C to 125°C, priced at $2.75 per unit. All prices are based on quantities of 1,000 units and all versions are available immediately. For more detailed information, visit www.linear.com/product/LT8609参照.

Photo Caption: 42V, 2A, 2.2MHz synchronous step-down DC/DC converter operating from 3.0V ~ 42V

Product Features: LT8609

• Wide input voltage range: 3.0V ~ 42V
• 2A continuous output current with 3A peak capability
• Ultra-low quiescent current Burst Mode® operation: 2.5μA IQ adjustable 12VIN ~ 3.3VOUT, output ripple < 10mVP-P
• High efficiency synchronous operation at fSW = 2MHz: 93% efficiency at 1A, 5VOUT from 12VIN
• Fast minimum switch on-time: 45ns
• Fast spread spectrum frequency modulation for low EMI
• Low dropout under all conditions
• Minimum output voltage of 0.8V
• Small inductor usable
• Adjustable & synchronizable: 200kHz ~ 2.2MHz
• Current mode operation
• Precise 1V enable pin threshold
• Internal compensation
• Output soft start & tracking
• Compact thermally enhanced 10-pin MSOP package

USA list prices presented are approximate for budgeting purposes and may vary depending on regional tariffs, taxes, fees and exchange rates