LT8631, 100 V, 1 A, Synchronous, Micropower, Step-Down Regulator

Analog Devices' LT8631 synchronous rectification delivers efficiency as high as 90% while Burst Mode® operation keeps quiescent current under 7 μA in no-load standby conditions

Image of Analog Devices' LT8631 Step-Down Regulator Analog Devices' LT8631 is a current-mode, PWM, step-down DC/DC converter with internal synchronous switches that provide current for output loads up to 1 A. The wide input range of 3 V to 100 V makes the LT8631 suitable for regulating power from a wide variety of sources including automotive and industrial systems and 36 V to 72 V telecom supplies. Low ripple Burst Mode operation enables high-efficiency operation down to very-low output currents while keeping the output ripple below 10 mVP-P. Resistor programmable 100 kHz to 1 MHz frequency range and synchronization capability enable optimization between efficiency and external component size. The soft-start feature controls the ramp rate of the output voltage, eliminating input current surge during start-up while also providing output tracking. A power good flag signals when the output voltage is within ±7.5% of the regulated output. Under-voltage lockout can be programmed using the EN / UV pin. Shutdown mode reduces the total quiescent current to less than 5 µA. The LT8631 is available in a 20-lead TSSOP package with exposed pad for low thermal resistance and high-voltage lead spacing.

Features
  • Ultrawide input voltage range: 3 V to 100 V
  • Output voltage range: 0.8 V to 60 V
  • Low ripple Burst Mode operation:
    • 16 µA IQ at 12 VIN to 5 VOUT output ripple <10 mVP-P
    • 7 µA IQ at 48 VIN to 5 VOUT output ripple <10 mVP-P
  • Low dropout: 99% maximum duty cycle
  • Thermally enhanced, 20-lead TSSOP with high voltage lead spacing
  • Fixed frequency operation: 100 kHz to 1 MHz
  • Synchronization input
  • Programmable under-voltage lockout
  • Power good flag
  • Flexible output voltage tracking
  • Short-circuit protection
  • Low shutdown current: 5 µA
  • Tolerates pin open and short faults
  • Peak current-mode control
  • Internal synchronous switches
Efficiency vs Load Current Graph

Image of Analog Devices' LT8631 Step-Down Regulator

Applications
  • Automotive supplies
  • Telecom supplies
  • Distributed supply regulation

LT8631 Step-Down Regulator

ImageManufacturer Part NumberDescriptionAvailable QuantityPriceView Details
IC REG BUCK ADJ 1A 20TSSOPLT8631EFE#PBFIC REG BUCK ADJ 1A 20TSSOP197 - Immediate$8.32View Details
IC REG BUCK ADJ 1A 20TSSOPLT8631HFE#PBFIC REG BUCK ADJ 1A 20TSSOP278 - Immediate$9.56View Details
IC REG BUCK ADJ 1A 20TSSOPLT8631IFE#PBFIC REG BUCK ADJ 1A 20TSSOP665 - Immediate$9.05View Details
Published: 2016-09-13