The LT®8642S synchronous step-down regulator features second generation Silent Switcher architecture designed to minimize EMI emissions while delivering high efficiency at high switching frequencies. This includes the integration of bypass capacitors to optimize all the fast current loops inside and make it easy to achieve advertised EMI performance by eliminating layout sensitivity. This performance makes the LT8642S ideal for noise sensitive applications and environments.
The fast, clean, low-overshoot switching edges enable high efficiency operation even at high switching frequencies, leading to a small overall solution size. Peak currentmode control with a 25ns minimum on-time allows high step down ratios even at high switching frequencies. External compensation via the VC pin allows for fast transient response at high switching frequencies. The VC pin also enables current sharing and a CLKOUT pin enables synchronizing other regulators to the LT8642S.
Burst Mode operation enables low standby current consumption, forced continuous mode can control frequency harmonics across the entire output load range, or spreadspectrum operation can further reduce EMI emissions. Soft-start and tracking functionality is accessed via the SS pin, and an accurate input voltage UVLO threshold can be set using the EN/UV pin.
Feature
- Ultralow EMI Emissions On Any PCB
- Eliminates PCB Layout Sensitivity
- Internal Bypass Capacitors Reduce Radiated EMI
- Optional Spread Spectrum Modulation
- Up to 96% Efficiency at 1MHz, 12VIN to 3.3VOUT
- Up to 95% Efficiency at 2MHz, 12VIN to 3.3VOUT
- n 240µA IQ Regulating 12VIN to 1.2VOUT
- Output Ripple < 10mVP-P
Applications
- General Purpose Step-Down
