MIC4574

The MIC4574 is a series of easy to use fixed and adjustable BiCMOS step-down (buck) switch-mode voltage regulators. The 200kHz MIC4574 duplicates the pinout and function of the 52kHz LM2574. The higher switching frequency may allow up to a 2:1 reduction in output filter inductor size.

The MIC4574 is available in 3.3V, and 5V fixed output versions or a 1.23V to 20V adjustable output version. Both versions are capable of driving a 0.5A load with excellent line and load regulation.

The feedback voltage is guaranteed to±2% tolerance for adjustable versions, and the output voltage is guaranteed to ±3% for fixed versions, within specified voltages and load conditions. The oscillator frequency is guaranteed to ±10%.

In shutdown mode, the regulator draws less than 200µA standby current. The regulator performs cycle-by-cycle current limiting and thermal shutdown for protection under fault conditions.

This series of simple switch-mode regulators requires a minimum number of external components and can operate using a standard series of inductors. Frequency compensation is provided internally.

The MIC4574 is available in DIP (N) packages for the industrial temperature range.

Features
  • Fixed 200kHz operation
  • 3.3V, 5V, and adjustable output versions
  • Voltage over specified line and load conditions:
  • Fixed version: ±3% max. output voltage
  • Adjustable version: ±2% max. feedback voltage
  • Guaranteed 0.5A switch current
  • Wide input voltage range: 4V to 24V
  • Wide output voltage range: 1.23V to 20V
  • Requires minimum external components
  • < 200µA typical shutdown mode
  • 75% efficiency (adjustable version > 75% typ.)
  • Standard inductors and capacitors are
  • 25% of typical LM2574 values
  • Thermal shutdown
  • Overcurrent protection
  • 100% electrical thermal limit burn-in
Parameter
Parameter Name Value Value
Regulator Type Step Down (Buck) Step Down (Buck)
# of Outputs 1 1
Input Voltage Range Min (V) 4 4
Input Voltage Range Max (V) 24 24
Output Voltage Range Min (V) 1.23 1.23
Quiescent Current (mA) typ 5 5
Switching Frequency (kHz) 200 200
Operating Temp Range -40 to 85 -40 to 85
Vfb (V) 1.23 1.23
Duty Cycle Max (%) 0.95 0.95
SHUTDOWN Current (µA) (Typ) 50 50
Documents
MIC4574 Data SheetData Sheets11/05/2015456KB
Micrel AN 2 - 200kHz MIC4574/5/6 Family Design GuideAppNote09/29/201536KB
Micrel AN 83 - Practical Switching Regulator CircuitsAppNote10/02/2015442KB
MIC4574 Evaluation BoardUser Guides11/11/201542KB
RoHS Information
PartNumberDeviceWeightShippingWeightLeadCountPackageTypePackageWidthSolderCompositionJEDECIndicatorRoHSChinaEFUP
MIC4574-3.3YN0.4867000.9000008PDIP.300inMatte Tine3
MIC4574-5.0YN0.4867000.9000008PDIP.300inMatte Tine3
MIC4574YN0.4867000.9000008PDIP.300inMatte Tine3
MIC4574 Data Sheet MIC4574
Micrel AN 2 MIC4575
Micrel AN 83 MIC4575
MIC4574 Evaluation Board MIC4574