LT1309 Linear Technology, LT1309 Datasheet
LT1309
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LT1309 Summary of contents
Page 1
... Quiescent current is 650 A decreasing when the part shuts down. The device includes a soft start feature which limits supply current transients during turn-on. The LT1309 contains a VPP VALID comparator with a logic output that goes low when the output voltage is ready to program 12V Flash Memory. This comparator simplifies the interface to external control logic ...
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... ON/OFF V = 0.2V ON/OFF V Rising (High to Low Transition) SENSE I = 100 A SINK I = 2.5 A SOURCE U W ORDER PART TOP VIEW NUMBER 8 ON/OFF LT1309CS8 7 SENSE 6 VPP VALID GND 5 S8 PART MARKING S8 PACKAGE 1309 = 150 C, = 150 C 3V, unless otherwise noted. MIN TYP MAX 650 900 9 15 ...
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... TEMPERATURE ( C) 1309 G02 800 700 600 500 400 300 75 100 –50 1309 G04 –50 75 100 1309 G06 LT1309 Switch Saturation Voltage 250 I = 500mA SW 225 200 175 150 125 100 100 –50 – TEMPERATURE ( C) Supply Current ...
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... A. ON/OFF (Pin 8): Shutdown Control. When pulled below 1.5V, this pin disables the LT1309 and reduces supply current All circuitry is disabled in shutdown. The part is enabled when ON/OFF is greater than 1.5V. Start-Up Waveforms, I ...
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... REF U OPERATIO The LT1309 is a current limited, Burst Mode (gated oscillator) type switching regulator that produces a 12V output from a 3. input. Operation can best be understood by referring to the Block Diagram. When the voltage at the Sense pin (Pin 7) is less than 12V, compara- tor C1 enables the oscillator, turning switches Q1 and Q2 on ...
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... U APPLICATIONS INFORMATION Inductor Selection The low inductance value required with the LT1309 (10 H) allows the use of very small units such as the Murata-Erie LQH3C100. Requirements for the inductor include low DCR, ability to perform efficiently at 500kHz and a satura- tion current rating of 700mA to 900mA. Often inductor manufacturers rate maximum current for a small inductor based on self-heating considerations ...
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... Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) 0.228 – 0.244 (5.791 – 6.197) 0.053 – 0.069 (1.346 – 1.752) 0 – 8 TYP 0.014 – 0.019 (0.355 – 0.483) LT1309 0.189 – 0.197* (4.801 – 5.004 0.150 – 0.157** (3.810 – 3.988) ...
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... LT1309 RELATED PARTS PART NUMBER DESCRIPTION LT1106 Micropower Step-Up DC/DC Converter, 12V at 60mA LT1109-12 Micropower Step-Up DC/DC Converter, 12V at 60mA LT1109A-12 Micropower Step-Up DC/DC Converter, 12V at 120mA ® LTC 1262 Inductorless Flash Memory Programming Supply, 12V at 30mA LT1303 Micropower High Efficiency DC/DC Converter with Low-Battery Detector ...