Linear Technology’s new LT8608 is a 1.5-A, 42-V input synchronous step-down switching regulator that delivers 93% efficiency while switching at 2 MHz. It is well suited for avoiding critical noise-sensitive frequency bands (e.g., AM radio) while using a compact footprint. Burst Mode operation keeps quiescent current under 2.5 µA in no-load standby conditions. Its 3-to-42-V input voltage range makes it ideal for automotive applications that must regulate through cold-crank and stop-start scenarios with minimum input voltages as low as 3 V and load dump transients in excess of 40 V. Its internal 2-A switches can deliver up to 1.5 A of continuous output current.
The LT8608 maintains a minimum dropout voltage of only 200 mV (at 500 mA) under all conditions. Spread-spectrum frequency modulation and special design techniques offer low EMI operation. In addition, a fast minimum on-time of only 45 ns enables 2-MHz constant frequency switching from a 16-V input to a 1.5-V output. The LT8608’s 10-lead thermally enhanced MSOP package and high switching frequency keeps external inductors and capacitors small for a thermally efficient footprint.
The LT8608’s features and specifications include:
- Wide input voltage range: 3 to 42 V
- Ultralow Quiescent Current Burst Mode operation:
- Less 2.5-µA IQ Regulating 12 VIN to 3.3 VOUT
- Output Ripple less than 10 mVPP
- High Efficiency 2-MHz Synchronous Operation:
- 93% Efficiency at 0.5 A, 5 VOUT from 12 VIN
- 1.5-A Maximum Continuous Output Current
- Fast Minimum Switch-On Time: 45 ns
- Adjustable and Synchronizable: 200 kHz to 2.2 MHz
- Spread-Spectrum Frequency Modulation for Low EMI
- Allows Use of Small Inductors
- Low Dropout
- Peak Current Mode Operation
- Accurate 1-V Enable Pin Threshold
- Internal Compensation
- Output Soft-Start and Tracking
- Small 10-Lead MSOP Package
Source: Linear Technology
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