Step-Down Switching Regulator: LT8612
Linear Technology Corp. announces the LT8612, a 6 A, 42 V input capable synchronous step-down switching regulator. Synchronous rectification delivers efficiency as high as 95% while Burst Mode® operation keeps quiescent current under 3µA in no-load standby conditions. Its 3.4 to 42 V input voltage range makes it ideal for automotive and industrial applications. Its internal high efficiency switches deliver up to 6 A of continuous output current to voltages as low as 0.97 V. The LT8612’s Burst Mode operation offers ultralow quiescent current, making it well suited for applications such as automotive “always-on” systems, which need to extend operating battery life. The LT8612’s unique design maintains a minimum dropout voltage of only 250 mV at 3 A under all conditions, enabling it to excel in scenarios such as automotive cold-crank. Furthermore, a fast minimum on-time of only 40ns enables 2 MHz constant frequency switching from a 16 V input to a 1.5V output. This enables designers to optimize efficiency while avoiding critical noise-sensitive frequency bands. The LT8612’s 28-lead 3 x 6 mm QFN package and high switching frequency keep external inductors and capacitors small, providing a compact, thermally efficient footprint.
The LT8612 utilizes internal top and bottom high efficiency power switches with the necessary boost diode, oscillator, control and logic circuitry integrated into a single die. Low ripple Burst Mode operation maintains high efficiency at low output currents while keeping output ripple below 10 mVPK-PK. Special design techniques and a new high speed process enable high efficiency over a wide input voltage range, and the LT8612’s current-mode topology enables fast transient response and excellent loop stability. Other features include internal compensation, a power good flag, output soft start/tracking and thermal protection.
The LT8612EUDE is packaged in a 3 x 6 mm QFN package and is priced starting at $4.95 each. An industrial temperature version, the LT8612IUDE, is tested and guaranteed to operate from a -40° to 125°C operating junction temperature and is priced at starting $5.45 each. All pricing is for 1,000 piece quantities and all versions are available from stock. For more information, visit www.linear.com/product/LT8612.
Summary of Features: LT8612
- Wide Input Voltage Range: 3.4V to 42V
- Ultralow Quiescent Current Burst Mode® Operation: 3µA IQ Regulating 12VIN to 3.3VOUT
- Output Ripple < 10mVP-P
High Efficiency Synchronous Operation:
- o 95% Efficiency at 3A, 5VOUT from 12VIN
- o 94% Efficiency at 3A, 3.3VOUT from 12VIN
- Fast Minimum Switch-On Time: 40ns
- Low Dropout Under All Conditions: 250mV at 3A
- Allows Use Of Small Inductors
- Safely Tolerates Inductor Saturation in Overload Conditions
- Adjustable & Synchronizable: 200kHz to 2.2MHz
- Current Mode Operation
- Accurate 1V Enable Pin Threshold
- Internal Compensation
- Output Soft-Start & Tracking
- Small Thermally Enhanced 3mm x 6mm 28-Lead QFN Package