Dual Channel 4A, 42V, Synchronous Step-Down Silent Switcher 2 with 6.2µA Quiescent Current

The LT8650S is a dual step-down regulator that delivers up to 4A of continuous current from both channels and supports loads up to 6A from each channel. The LT8650S features the second generation Silent Switcher architecture to minimize EMI emissions while delivering high efficiency at high switching frequencies. This includes integration of bypass capacitors to optimize high frequency current loops and make it easy to achieve advertised EMI performance by eliminating layout sensitivity.

The fast, clean, low-overshoot switching edges enable high efficiency operation even at high switching frequencies, leading to a small overall solution size. Peak current mode control with a 40ns minimum on-time allows high step down ratios at high switching frequencies.

Burst Mode operation features a 6.2μA quiescent current resulting in high efficiency at low output currents, forced continuous mode allows fixed switching frequency operation over the entire output load range, and spread spectrum operation can further reduce EMI emissions. External VC pins allow optimal loop compensation for fast transient response. The VC pins can also be used for current sharing and the CLKOUT pin enables synchronizing two LT8650S chips to generate a 4-phase, 16A supply.

Applications

* General Purpose Step-Down

* Automotive and Industrial Supplies

* Silent Switcher®2 Architecture:

* Ultralow EMI on Any PCB

* Eliminates PCB Layout Sensitivity

* Internal Bypass Capacitors Reduce Radiated EMI

* Optional Spread Spectrum Modulation

* 4A DC from Each Channel Simultaneously

* Up to 6A on Either Channel

* Ultralow Quiescent Current Burst Mode® Operation:

* 6.2μA IQ Regulating 12VIN to 5VOUT1 and 3.3VOUT2

* Output Ripple <10mVP-P