LTC1983-5 Linear Technology, LTC1983-5 Datasheet
LTC1983-5
Related parts for LTC1983-5
LTC1983-5 Summary of contents
Page 1
... Fixed Output Voltages: –3V, –5V or Low Noise V to –V Inverted Output IN 4% Output Voltage Accuracy Low Quiesient Current 100mA Output Current Capability 3V to 5.5V Operating Voltage Range (LTC1983-3) 2.3V to 5.5V Operating Voltage Range (LTC1983-5) Internal 900kHz Oscillator “Zero Current” Shutdown Short-Circuit and Over-Temperature Protected TM Low Profile (1mm) ThinSOT Package U APPLICATIO S – ...
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... V to GND ................................................... –0. SHDN Voltage .............................................. –0. GND (LTC1983-3) .................. 0. OUT V to GND (LTC1983-5) .................. 0. OUT I Max ............................................................. 125mA OUT Output Short-Circuit Duration .......................... Indefinite Operating Temperature Range (Note 2) ...– Storage Temperature Range ................. – 125 C Lead Temperature (Soldering, 10 sec).................. 300 C ...
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... OUT 1983 G01 Efficiency vs I OUT 100 V = –3V OUT 3. 0.01 0 100 I (mA) OUT 1983 GO4 Open-Loop Current vs Temperature (LTC1983-5) 4 4.7 4.5 4.3 4.1 3.9 3.7 3.5 – 110 TEMPERATURE ( C) 1983 G07 LTC1983-3/LTC1983-5 Output Impedance vs Input Voltage 12 25mA OUT 12 11.5 11.0 10 ...
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... LTC1983-3/LTC1983 TYPICAL PERFOR A CE CHARACTERISTICS www.DataSheet4U.com Burst Mode Input Current vs V (LTC1983- 30.5 30.0 29.5 29.0 28.5 28.0 27.5 27.0 26.5 3.1 3.6 4.1 4.6 5.1 5.5 V (V) IN 1983 G10 SHDN Pin Input Current vs Temperature 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 – 100 150 TEMPERATURE ( C) 1983 G13 V Ripple at 100mA Load OUT V OUT 20mV 1 s/DIV 1983 G16 ...
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... S2B V OUT CHARGE PUMP C OUT 10 F LTC1983-3/LTC1983-5 – C (Pin 4): Charge Pump Flying Capacitor Negative Termi- nal. This node is switched between GND and V connected to GND during shutdown). GND (Pin 5): Signal and Power Ground for the 6-Pin SOT-23 package. This pin should be tied to a ground plane OUT for best performance ...
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... Block Diagram) The LTC1983-3/LTC1983-5 use a switched capacitor charge pump to invert a positive input voltage to a regu- lated –3V 4% (LTC1983-3) or –5 4% (LTC1983-5) output voltage. Regulation is achieved by sensing the output voltage through an internal resistor divider and enabling the charge pump when the output voltage droops above the upper trip point of COMP1 ...
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... A large flying capacitor OUT (>1 F) also increases ripple for the same reason. Large output current load and/or a small output capacitor (<10 F) LTC1983-3/LTC1983-5 results in higher ripple due to higher output voltage dV/dt. High ESR capacitors (ESR > 0 the output pin cause high frequency voltage spikes on V cycle ...
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... LTC1983-3/LTC1983-5 U OPERATIO www.DataSheet4U.com (Refer to Block Diagram) Inrush Currents During normal operation, V will experience current tran- IN sients in the several hundred milliamp range whenever the charge pump is enabled. During start-up, these inrush currents may approach amps. For this reason important to minimize the source resistance between the input supply and the V pin ...
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... A clean board layout using a ground plane and short connections to all capacitors will improve perfor- mance and ensure proper regulation under all conditions (refer to Figures 4a and 4b). You will not get advertised performance with careless layout. V OUT V OUT LTC1983-3/LTC1983-5 1000 100 2.3V TO 5.5V IN ...
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... DC/DC Converter OUT 2.5V 4 LTC1983-5 CERAMIC CERAMIC SHDN GND OFF ON + – 1983 TA03 0.47 F CERAMIC 100mA Inverting DC/DC Converter OUT LTC1983-5 CERAMIC GND SHDN OFF ON + – 1983 TA04 1 F CERAMIC V OUT –2.5V V OUT –V IN sn1983 1983fs ...
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... U S6 Package 6-Lead Plastic SOT-23 (Reference LTC DWG # 05-08-1636) 0.854 0.127 1.50 – 1.75 2.80 BSC (NOTE 4) 0.95 BSC 0.80 – 0.90 1.00 MAX 0.09 – 0.20 (NOTE 3) LTC1983-3/LTC1983-5 2.90 BSC (NOTE 4) PIN ONE ID 0.30 – 0.45 TYP 6 PLCS (NOTE 3) 0.01 – 0.10 1.90 BSC S6 TSOT-23 0801 sn1983 1983fs 11 ...
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... Constant Frequency Doubler Charge Pump Linear Technology Corporation 12 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear.com Combined Unregulated Doubler and Regulated Inverter OUT LTC1983- LTC1983-5 CERAMIC SHDN GND + – BOOST BOOST C OUT2 ...