lt1944-1ems-trpbf Linear Technology Corporation, lt1944-1ems-trpbf Datasheet
lt1944-1ems-trpbf
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lt1944-1ems-trpbf Summary of contents
Page 1
... DC/DC con- verter in a 10-pin MSOP package. Each converter is designed with a 350mA current limit and an input voltage range of 1.2V to 15V, making the LT1944 ideal for a wide variety of applications. Both converters feature a quies- cent current of only load, which further reduces to 0 ...
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... 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 is guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... 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 Quiescent Current 1.23V ...
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... GND 3 U OPERATIO The LT1944 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 (or at least provides a good starting point). This value pro- vides a good tradeoff in inductor size and system perfor- mance. Pick a standard inductor close to this value. A ...
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... 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 (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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... TA02a U MS10 Package 10-Lead Plastic MSOP (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 5V 40mA 324k 604k 3.3V 80mA 1944 TA02 2-Cell to 3.3V Efficiency ...
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... Four Output Power Supply for Color LCD Displays C6 2.2 F D3A D3B SW1 SHDN1 FB1 LT1944 4 5 SHDN2 FB2 140k GND PGND PGND SW2 WHITE LEDs C1: TAIYO YUDEN JMK212BJ475 (408) 573-4150 ...