IC-Hersteller Analog Devices

IC-Hersteller (103)

Analog Devices LT8640

42V, 5A Synchronous Step-Down Silent Switcher with 2.5μA Quiescent Current

Details

TopologieAbwärtswandler
Eingangsspannung3.4-42 V
Schaltfrequenz1000-3000 kHz
Ausgang 15 V / 5 A
IC-RevisionE

Beschreibung

The LT8640/LT8640-1 step-down regulator features Silent Switcher architecture designed to minimize EMI emissions while delivering high efficiency at frequencies up to 3MHz. An ultralow 2.5µA quiescent current—with the output in full regulation—enables applications requiring highest efficiency at very small load currents.The LT8640/LT8640-1 allows high VIN to low VOUT conversion at high frequency with a fast minimum top switch on-time of 30ns. The SYNC/MODE pin selects between Burst Mode operation, spread spectrum mode, synchronization to an external clock, and either pulse-skipping (LT8640) or forced continuous mode (LT8640-1).

Eigenschaften

  • Silent Switcher® Architecture
  • Ultralow EMI Emissions
  • Spread Spectrum Frequency Modulation
  • High Efficiency at High Frequency
  • Up to 96% Efficiency at 1MHz, 12VIN to 5VOUT
  • Up to 95% Efficiency at 2MHz, 12VIN to 5VOUT
  • Wide Input Voltage Range: 3.4V to 42V
  • 5A Maximum Continuous Output, 7A Peak Transient Output
  • Ultralow Quiescent Current Burst Mode® Operation
  • 2.5µA IQ Regulating 12VIN to 3.3VOUT
  • Output Ripple < 10mVP-P
  • Fast Minimum Switch On-Time: 30ns
  • Low Dropout Under All Conditions: 100mV at 1A
  • Forced Continuous Mode (LT8640-1 Only)
  • Safely Tolerates Inductor Saturation in Overload
  • Adjustable and Synchrnizable: 200kHz to 3MHz
  • Peak Current Mode Operation
  • Output Soft-Start and Tracking
  • Small 18-Lead 3mm × 4mm QFN and Side Wettable QFN
  • AEC-Q100 Qualified for Automotive Applications

Typische Anwendungen

  • Automotive and Industrial Supplies, GSM Power Supplies

Weiterführende Informationen

Artikeldaten

Artikel Nr.
Daten­blatt
Simu­lation
Downloads
Status
Produktserie
L(µH)
IRP,40K(A)
ISAT,10%(A)
ISAT,30%(A)
RDC max.(mΩ)
fres(MHz)
Montageart
Z @ 100 MHz(Ω)
Zmax(Ω)
Testbedingung Zmax
IR(mA)
Z @ 1 GHz(Ω)
H(mm)
Typ
Muster
WE-LHMI SMT Speicherdrossel, 1.5 µH, 9.1 A
Simu­lation
Status Aktivi| Produktion ist aktiv. Erwartete Lebenszeit: >10 Jahre.
Induktivität1.5 µH
Performance Nennstrom9.1 A
Sättigungsstrom 111.2 A
Sättigungsstrom @ 30%27.6 A
Gleichstromwiderstand15 mΩ
Eigenresonanzfrequenz45 MHz
MontageartSMT 
Höhe2.8 mm
WE-MPSB EMI Multilayer Power Suppression Bead, –, –
Simu­lation
Status Aktivi| Produktion ist aktiv. Erwartete Lebenszeit: >10 Jahre.
Gleichstromwiderstand6 mΩ
MontageartSMT 
Impedanz @ 100 MHz100 Ω
Maximale Impedanz160 Ω
Maximale Impedanz1100 MHz 
Nennstrom8000 mA
Impedanz @ 1 GHz150 Ω
Höhe2.3 mm
TypHochstrom