LT1505CG-1 Linear Technology, LT1505CG-1 Datasheet
LT1505CG-1
Specifications of LT1505CG-1
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LT1505CG-1 Summary of contents
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... A sleep mode when the wall adapter is un- plugged. A logic output indicates Li-Ion full charge when current drops to 20% of the programmed value. The LT1505 is available in a 28-pin SSOP package. , LTC and LT are registered trademarks of Linear Technology Corporation. *US Patent No. 5,723,970 V BOOST BOOSTC ...
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... BGATE GBIAS LT1505CG BOOSTC BAT SPIN 22 21 SENSE BAT2 20 19 PROG 3CELL 16 15 4.2V G PACKAGE NOTE: LT1505CG-1 DOES NOT HAVE INPUT CURRENT = 125 C, = 100 LIMITING FUNCTION (LT1505), no load on any CLN CC MIN TYP MAX 100 105 92 108 2.453 2.465 2.477 A 2.441 2 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T outputs unless otherwise noted. PARAMETER Preset Battery Voltage (12.3V, 16.4V, 12.6V, 16.8V) All Preset Battery Voltages Preset Battery Voltage Tolerance BAT2 Pin Input Current Voltage Setting Resistors Tolerance (R4, R5, R6, ...
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LT1505 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T outputs unless otherwise noted. PARAMETER Voltage Amplifier VA Transconductance (Note 3) Output Source Current V Input Bias Current FB Current Limit Amplifier CL1 Turn-On Threshold Transconductance CLP Input Current CLN ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Efficiency of Figure 1 Circuit 105 V = 19V 12.6V BAT 100 (A) BAT 1505 G01 (Voltage Amplifier) FB ...
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LT1505 PIN FUNCTIONS BOOST (Pin 1): This pin is used to bootstrap and supply power for the topside power switch gate drive and control circuity. In normal operation, V BOOST internally generated 8.6V regulator V + 9.1V ...
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PIN FUNCTIONS the noninverting input to the amplifier the Block Diagram, that controls the charging current when the device operates in constant voltage mode. The amplifier VA controls the charging current to maintain the voltage ...
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LT1505 W BLOCK DIAGRAM (LT1505 – 6. 6. BAT 0.2V E1 – SHUTDOWN – GBIAS SHDN – ...
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TEST CIRCUITS V C 75k 0.047 0.65V CAP 0.047 F + FLAG 2V 1k – + 0.033 F LT1013 20k Test Circuit 1 LT1505 – CA1 CA2 REF PROG 300 PROG ...
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LT1505 U OPERATION The LT1505 is a synchronous current mode PWM step- down (buck) switcher. The battery DC charge current is pro- grammed by a resistor R (or a DAC output current) at PROG the PROG pin and the ratio ...
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U U APPLICATIONS INFORMATION EMI considerations usually make it desirable to minimize ripple current in the battery leads. Beads or inductors may be added to increase battery impedance at the 200kHz switching frequency. Switching ripple current splits be- tween the ...
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LT1505 U U APPLICATIONS INFORMATION This is accomplished by sensing total adapter output current and adjusting charge current downward if a preset adapter current limit is exceeded. True analog control is used, with closed loop feedback ensuring that adapter load ...
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U U APPLICATIONS INFORMATION Preset Battery Voltage Settings The LT1505 provides four preset battery voltages: 12.3V, 12.6V, 16.4V and 16.8V. See the Pin Functions section for pin setting voltage selection. An internal switch connects the resistor dividers to the battery ...
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LT1505 U U APPLICATIONS INFORMATION amplifier CA1. They are not needed if V higher than V . The PFET M3 is optional and can be BAT replaced with a diode least 3V higher than V IN ...
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... Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Fast Charge, Longer Battery Life, Crisis Management CHARGE www.linear.com 7.65 – 7.90 (.301 – .311 1.73 – 1.99 (.068 – .078) .05 – .21 (.002 – .008) G28 SSOP 0501 1505fc LT/TP 1101 1.5K REV C • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1999 ...