42V, 3.5A Synchronous Step-Down Regulator with 2.5μA Quiescent Current

The LT8610AC/LT8610AC-1 is a compact, high efficiency, high speed synchronous monolithic step-down switching regulator that consumes only 2.5μA of quiescent current. Compared to the LT8610AB, the LT8610AC/LT8610AC-1 has a lower feedback voltage of 800mV and a lower minimum VIN of 3V. The LT8610AC/LT8610AC-1 has the same additional features of the LT8610AB as compared to the LT8610: higher maximum output current of 3.5A, faster minimum on time of 30ns, and higher light load efficiency.

The LT8610AC/LT8610AC-1 has a SYNC pin for synchronization to an external clock. A capacitor on the TR/SS pin programs the output voltage ramp rate during startup. The PG flag signals when VOUT is within ±8% of the programmed output voltage as well as fault conditions. 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.

Feedback Voltage

Min VIN

Output Current

Notes

LT8610AC-1

0.80V

3.0V

3.5A

FSW = 1.5MHz to 2.2MHz, Optimized Transient Response

LT8610AC

0.80V

3.0V

3.5A

FSW = 200kHz to 2.2MHz

LT8610AB

0.97V

3.4V

3.5A

Improved Burst Mode Efficiency

LT8610AX

0.97V

3.4V

3.5A

175°C Max Junction Temp

LT8610A

0.97V

3.4V

3.5A

Higher IOUT, 30ns Min On Time

LT8610

0.97V

3.4V

2.5A

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Applications

* Automotive and Industrial Supplies

* GSM Power Supplies

* LT8610 Feature Set, Plus:

* 3V Minimum Input Voltage

* 800mV Feedback Voltage

* 3.5A Maximum Output Current

* Fast 30ns Minimum Switch-On Time

* Improved Burst Mode Efficiency

* Improved EMI

* Wide Input Voltage Range: 3V to 42V

* Ultralow Quiescent Current Burst Mode® Operation:

* 2.5μA IQ Regulating 12VIN to 3.3VOUT

* Low Dropout Under All Conditions: 200mV at 1A