LTC3890-2 - 60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller

The LTC®3890-2 is a high performance dual step-down switching regulator DC/DC controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phaselockable frequency of up to 850kHz. Power loss and noise due to the ESR of the input capacitor are minimized by operating the two controller output stages out-of-phase.

The 50μA no-load quiescent current extends operating run time in battery-powered systems. OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. A wide 4V to 60V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.

Independent TRACK/SS pins for each controller ramp the output voltages during start-up. Current mode control limits the inductor current during short-circuit conditions. The PLLIN/MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous conduction mode at light loads. For versions with different and/or additional features, see the LTC3890 family summary, Table 1, in the Pin Functions section of this data sheet.

Features
  • Wide VIN Range: 4V to 60V (65V Abs Max)
  • Low Operating IQ: 50μA (One Channel On)
  • Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 24V
  • RSENSE or DCR Current Sensing
  • Out-of-Phase Controllers Reduce Input Capacitance and Power Supply Induced Noise
  • Phase-Lockable Frequency (75kHz to 850kHz)
  • Programmable Fixed Frequency (50kHz to 900kHz)
  • Selectable Continuous, Pulse-Skipping or Low Ripple Burst Mode® Operation at Light Loads
  • Selectable Current Limit
  • Very Low Dropout Operation: 99% Duty Cycle
  • Adjustable Output Voltage Soft-Start or Tracking
  • Power Good Output Voltage Monitors
  • Low Shutdown IQ : < 14μA
  • Internal LDO Powers Gate Drive from VIN or EXTVCC
  • Small Low Profile (0.75mm) 5mm × 5mm QFN Package
Typical Application
LTC3890-2 Typical Application
LTC3890-2 Typical Application
Applications
  • Automotive Always-On Systems
  • Battery Operated Digital Devices
  • Distributed DC Power Systems
Packaging
LTC3890-2 Package Drawing
Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
LTC3890EUH-2#PBF5x5 QFN-32E$6.56$4.59
LTC3890EUH-2#TRPBF5x5 QFN-32E$4.65
LTC3890HUH-2#PBF5x5 QFN-32H$7.99$5.59
LTC3890HUH-2#TRPBF5x5 QFN-32H$5.65
LTC3890IUH-2#PBF5x5 QFN-32I$7.56$5.29
LTC3890IUH-2#TRPBF5x5 QFN-32I$5.35
LTC3890MPUH-2#PBF5x5 QFN-32MP$22.51$15.76
LTC3890MPUH-2#TRPBF5x5 QFN-32MP$15.82
Demo Boards
Part NumberDescriptionPrice
DC2236A-ALTC3890EUH-2 Demo Board | 16V ≤ VIN ≤ 60V; VOUT = 12V @ 25A$200.00
Datasheet
Reliability Data
CAD Symbol
LTspice
LTpowerCAD
Related Products
LTC3890-2 - 60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller
R526 - Reliability Data
LTC3890-2 Footprints and Symbols
LTC3890-2 Demo Circuit - Automotive 12V SEPIC and 3.3V Step-Down Converter (5-35V to 12V @ 2A and 3.3V @ 10A)
LTC3890 Project - Low Iq, 2-Phase Synchronous Step-Down DC/DC Supply with Inductor DCR Current Sensing (16-55V to 12 @ 25A)
LTC3890 Project - Low Iq, 2-Phase Synchronous Step-Down DC/DC Supply with Rsense Current Sensing (16-55V to 12 @ 25A)