LT1944-1EMS#TRPBF Linear Technology, LT1944-1EMS#TRPBF Datasheet
LT1944-1EMS#TRPBF
Specifications of LT1944-1EMS#TRPBF
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LT1944-1EMS#TRPBF Summary of contents
Page 1
... The 1.5 s off-time converter is ideal for generating an output voltage that is close to the input voltage (i.e. a Li- Ion to 5V converter two-cell to 3.3V converter). With an input voltage range of 1.2V to 15V, the LT1944-1 is ideal for a wide variety of applications. Both converters feature a quiescent current of only load, which further reduces to 0 ...
Page 2
... SHDN Input Voltage Low Switch Leakage Current Switch Off, V Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The LT1944-1E is guaranteed to meet performance specifications from Specifications over the – operating 2 U PACKAGE/ORDER I FOR ATIO ...
Page 3
... Input Supply Pin. Bypass this pin with a IN capacitor as close to the device as possible. SW1 (Pin 10): Switch Pin for Switcher 1. This is the collector of the internal NPN power switch. Minimize the metal trace area connected to the pin to minimize EMI. LT1944-1 Quiescent Current 1.23V ...
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... SWITCHER 1 GND 3 U OPERATIO The LT1944-1 uses a constant off-time control scheme to provide high efficiencies over a wide range of output current. Operation can be best understood by referring to the block diagram in Figure 1. Q1 and Q2 along with R3 and R4 form a bandgap reference used to regulate the output voltage. When the voltage at the FB1 pin is slightly above 1 ...
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... Inductor Selection—Boost Regulator The formula below calculates the appropriate inductor value to be used for a boost regulator using the LT1944-1 (or at least provides a good starting point). This value provides a good tradeoff in inductor size and system performance. Pick a standard inductor close to this value. ...
Page 6
... To reduce the output ripple, increase the output capacitor value or add a 4.7pF feed-forward capaci- tor in the feedback network of the LT1944-1 (see the circuits in the Typical Applications section). Adding this small, inexpensive 4.7pF capacitor will greatly reduce the output voltage ripple ...
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... Plastic MSOP (Reference LTC DWG # 05-08-1661) 0.034 0.043 (0.86) (1.10) REF MAX SEATING PLANE 0.007 – 0.011 0.005 0.002 (0.17 – 0.27) (0.13 0.05) 0.0197 (0.50) BSC LT1944-1 24V 1mA 53.6k 324k 40mA 1944-1 TA02 0.118 0.004* (3.00 0.102) 10 ...
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... Burst Mode is a trademark of Linear Technology Corporation Linear Technology Corporation 8 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 Four Output Power Supply ( 5V, 15V 0 4.7pF 1M V SW2 SHDN2 FB2 LT1944 SHDN1 FB1 324k GND PGND PGND SW1 178k 4.7pF 0.1 F COMMENTS 3 ...