42V, 3.5A Synchronous Step-DownThe LT8610AC is a compact, high efficiency, high speed synchronous monolithic step-down switching regulator that consumes only 2.5µA of quiescent current. It has a low feedback voltage of 800mV and a low minimum VIN of 3V. Additional features include high maximum output current of 3.5A, fast minimum on time of 30ns, high light load efficiency and there is a SYNC pin for synchronization to an external clock. The 3.0V to 42V input voltage range of this device makes it ideal for automotive applications.
The LT8610AC from Linear Technology is a 3.5A, 42V input capable synchronous step-down switching regulator. Synchronous rectification delivers efficiency as high as 96%, while Burst Mode® operation keeps quiescent current under 2.5µA in no-load standby conditions.
The device’s 3.0V to 42V input voltage range makes it ideal for automotive applications, which must regulate through cold-crank/stopstart scenarios with minimum input voltages as low as 3.0V and load dump transients in excess of 40V. Its internal 5A switches can deliver up to 3.5A of continuous output current to voltages as low as 0.80V.
The LT8610AC’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 LT8610AC’s unique design maintains a minimum dropout voltage of only 200mV at 1A under all conditions, enabling it to excel in conditions such as automotive cold-crank.
Furthermore, a fast minimum on-time of only 30ns enables 2MHz constant frequency switching from a 16V input to a 1.0V output, optimizing efficiency while avoiding critical noise-sensitive frequency bands. The LT8610AC’s 16-lead thermally enhanced MSOP package and high switching frequency keeps external inductors and capacitors small, providing a compact, thermally efficient footprint.
The LT8610AC 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 10mVPK-PK.
Special design techniques and a new high speed process enable high efficiency over a wide input voltage range, and the LT8610AC’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 LT8610AC-1 has internal compensation optimized for high switching frequencies resulting in improved transient response compared to the LT8610AC. The LT8610AC-1 also has a feature which will soft-start the part when exiting dropout or brownout conditions reducing output voltage overshoot.
The LT8610ACEMSE is packaged in thermally enhanced MSOP-16 package and is priced at $3.75 each. An industrial temperature version, the LT8610ACIMSE, is tested and guaranteed to operate from a -40°C to 125°C operating junction temperature and is priced at $4.13.
An automotive temperature version, the LT8610ACHMSE, is tested and guaranteed to operate from a -40°C to 150°C operating junction temperature, priced at $4.38 each. All pricing is for 1,000 piece quantities and all versions are available from stock.
The USA list pricing shown is for budgetary use only. International prices may differ due to local duties, taxes, fees and exchange rates.
For more information, visit www.linear.com/product/LT8610AC .
Summary of Features of the LT8610AC:
- Wide Input Voltage Range: 3.0V to 42V
- Up to 3.5A of Continuous Output Current
- Ultralow Quiescent Current Burst Mode® Operation:
- 2.5µA IQ Regulating 12VIN to 3.3VOUT, Output Ripple < 10mVP-P
-
High Efficiency Synchronous Operation:
- 95% Efficiency at 1A, 5VOUT from 12VIN
- 93% Efficiency at 1A, 3.3VOUT from 12VIN
- Fast Minimum Switch-On Time: 30ns
- Low Dropout Under All Conditions: 200mV at 1A
- Minimum Output Voltage of 0.8V
- Allows Use of Small Inductors
- Adjustable & Synchronizable: 200kHz to 2.2MHz
- Current Mode Operation
- Accurate 1V Enable Pin Threshold
- Internal Compensation
- Output Soft-Start & Tracking
- Small Thermally Enhanced 16-Lead MSOP Package
Typical Application


Applications
- Automotive and Industrial Supplies
- GSM Power Supplies
Linear Technology (UK) Limited
Tel: +44 (0)1628 477066
E-mail: uksales@linear.com
Web site: www.linear.com
Website for product information: http://www.linear.com/product/LT8610ACRegulator with 2.5µA Quiescent Current