MAX1730:50mA, Regulated, Step-Down Charge Pump for 1.8V or 1.9V Logic

The MAX1730 regulated step-down charge pump generates up to 50mA at fixed output voltages of 1.8V or 1.9V from an input voltage in the 2.7V to 5.5V range. Specifically designed to provide high-efficiency logic supplies in applications that demand a compact design, the MAX1730 employs fractional conversion techniques to provide efficiency exceeding that of a linear regulator. The MAX1730 operates at up to 2MHz, permitting the use of small 0.22µF flying capacitors while maintaining low 75µA quiescent supply current. Proprietary soft-start circuitry prevents excessive current from being drawn from the supply during startup, making the MAX1730 compatible with higher impedance sources such as alkaline and lithium-ion cells. The MAX1730 is available in a space-saving 10-pin µMAX® package that is only 1.09mm high and occupies one-half the area of an 8-pin SO.

Key Features
  • > 85% Peak Efficiency
  • 50mA Guaranteed Output Current
  • Dual-Mode 1.8V or 1.9V Output
  • ±3% Output Voltage Accuracy
  • Up to 2MHz Operating Frequency
  • Small 0.22µF Capacitors
  • No Inductor Required
  • 2.7V to 5.5V Input Voltage Range
  • Output Disconnects from Input in Shutdown Mode
  • Small 10-Pin µMAX Package (1.09mm max height)
MAX1730: Typical Operating Circuit
MAX1730: Typical Operating Circuit
Applications/Uses
  • Handheld Instruments (PDAs, Palmtops)
  • Low-Voltage Logic Supplies
  • PC Cards
  • PDAs
  • Wireless Handsets
DataSheet
titleDownload file
MAX1730 Data SheetMAX1730.pdf
Parametrics
Part NumberTopologyVIN
(V)
VIN
(V)
ICC
(mA)
Unadj. VOUT
(V)
IOUT
(A)
Oper. Freq.
(kHz)
Oper. Temp.
(°C)
Package/PinsBudgetary
Price
minmaxmaxtypSee Notes
MAX1730Regulated2.75.50.151.8
1.9
0.052000-40 to +85µMAX/10$1.45 @1k
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX1730EUBNo Longer AvailableµMAX,;10 pin;15.4 mm²-40°C to +85°CNo
MAX1730EUB+ActiveµMAX,;10 pin;15.4 mm²-40°C to +85°CLead Free
MAX1730EUB+TActiveµMAX,;10 pin;15.4 mm²-40°C to +85°CLead Free
MAX1730EUB-TNo Longer AvailableMAX1730EUB+TµMAX,;10 pin;15.4 mm²-40°C to +85°CNo
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