LT1934-1 Linear Technology, LT1934-1 Datasheet
LT1934-1
Related parts for LT1934-1
LT1934-1 Summary of contents
Page 1
... FEATURES Wide Input Voltage Range: 3.2V to 34V Micropower Operation 250mA from 6.5V to 34V Input (LT1934 60mA from 6.5V to 34V Input (LT1934-1) 3.3V at 250mA from 4.5V to 34V Input (LT1934) 3.3V at 60mA from 4.5V to 34V Input (LT1934-1) Low Shutdown Current: <1 A Low V Switch: 200mV at 300mA CESAT Low Profile (1mm) SOT-23 (ThinSOT ...
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... C T 125 300mA (LT1934 75mA (LT1934-1) SW LT1934 LT1934 300mA (LT1934 75mA (LT1934- 300mA (LT1934 75mA (LT1934-1) SW www.DataSheet4U.com ORDER PART NUMBER LT1934ES6 LT1934ES6 LT1934IS6 LT1934IS6-1 4 SHDN S6 PART MARKING LTXP = 102 LTF8 LTAJB ...
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... LT1934-1 100 0 –50 – 100 125 TEMPERATURE ( C) 1934 G05 LT1934/LT1934-1 www.DataSheet4U.com MIN TYP MAX UNITS 0 2.3 V 0.25 V LT1934-1 Efficiency OUT 100 LT1934 OUT L = 150 12V 24V 0 100 LOAD CURRENT (mA) ...
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... LT1934/LT1934 TYPICAL PERFOR A CE CHARACTERISTICS Frequency Foldback 0.2 0.4 0.8 1.0 1.2 0.6 FEEDBACK PIN VOLTAGE (V) 1934 G07 Quiescent Current vs Temperature –50 – TEMPERATURE ( C) Minimum Input Voltage V = 3.3V OUT 6.0 LT1934 V = 3.3V OUT 5 BOOST DIODE TIED TO OUTPUT 5 ...
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... Connect this pin to the inductor, catch diode and boost capacitor. + – ON TIME DELAY S Q OFF TIME 1.8 s DELAY + 1.25V ENABLE – FEEDBACK COMPARATOR LT1934/LT1934-1 www.DataSheet4U.com pin. IN pin supplies current to the LT1934’ BOOST OUT C1 D1 1934 BD 1934f 5 ...
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... Page Schematic) 6 the flip-flop when this current reaches 400mA (120mA for the LT1934-1). After the 1.8 s delay of the off-time one-shot, the cycle repeats. Generally, the LT1934 will reach current limit on every cycle—the off time is fixed and the on time is regulated so that the LT1934 operates at the correct duty cycle. The 1.8 s off time is lengthened when the FB pin voltage falls below 0.8V ...
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... The lower peak switch current allows the use of smaller components (input capacitor, inductor and output capacitor). The ripple current at the input of the LT1934-1 circuit will be smaller and may be an important consideration if the input supply is current limited or has high impedance. The LT1934-1’s current draw during faults (output overload or short) and start-up is lower ...
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... LT1934 and to force this switching current into a tight local loop, minimizing EMI. The input capacitor must have low impedance at the switching frequency to do this effectively. A 2.2 F ceramic capacitor (1 F for the LT1934-1) satisfies these requirements. ~0.8I (ignor- LIM If the input source impedance is high, a larger value capacitor may be required to keep input ripple low ...
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... I • ESR. ESR should be less than ~150m LIM for the LT1934 and less than ~500m for the LT1934-1. The value of the output capacitor must be large enough to accept the energy stored in the inductor without a large change in output voltage. Setting this voltage step equal to ...
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... LT1934/LT1934 APPLICATIO S I FOR ATIO when used with ceramic capacitors will be lower and may be acceptable. A final precaution regarding ceramic capacitors concerns the maximum input voltage rating of the LT1934. A ceramic input capacitor combined with trace or cable inductance forms a high quality (under damped) tank circuit ...
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... C1. Additionally, the SW and BOOST nodes should be kept as small as possible. Finally, keep the FB node as small as possible so that the ground pin and LT1934/LT1934-1 www.DataSheet4U.com pin is grounded while the output IN 5 ...
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... LT1934 to help remove heat from the LT1934 to the ground plane. Hot Plugging Safely The small size, robustness and low impedance of ceramic capacitors make them an attractive option for the input bypass capacitor of LT1934 and LT1934-1 circuits. How- ever, these capacitors can cause problems if the LT1934 ...
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... An alternative solution is shown in Figure 7c resistor LT1934 V IN 10V/DIV 2 10A/DIV STRAY INDUCTANCE DUE TO 6 FEET (2 METERS) OF (7a) TWISTED PAIR LT1934 + 2.2 F (7b) 1 LT1934 2.2 F (7c) LT1934 (7d) 4.7 LT1934 (7e) LT1934/LT1934-1 www.DataSheet4U.com 10 s/DIV 1934 F07 1934f 13 ...
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... Voltage overshoot gets worse with reduced input capaci- tance. Figure 7d shows the hot plug response with ceramic input capacitor, with the input ringing above 40V. The LT1934-1 can tolerate a larger input resistance, such as shown in Figure 7e where a 4.7 resistor damps the voltage transient and greatly reduces the input current glitch on the 24V supply ...
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... LT1934-1 10pF ON OFF SHDN FB GND C1: TAIYO YUDEN JMK316BJ226ML C2: TAIYO YUDEN GMK316BJ105ML D1: ZETEX ZHCS400 OR ON SEMI MBR0540 D2: CENTRAL CMPD914 L1: COILCRAFT DO1608C-154 OR WURTH ELECTRONICS WE-PD4 TYPE S LT1934/LT1934-1 www.DataSheet4U.com D2 L1 100 H V OUT 3.3V 45mA 604k 1934 TA04 D2 L1 150 H ...
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... D2: CENTRAL CMPD914 L1: SUMIDA CR43-330 D3 + L1B 50 H • C1 L1A BOOST • LT1934-1 D4 10V 1 F SHDN FB 390k 715k GND D1: ON SEMICONDUCTOR MBR0540 D2, D3: BAT54 D4: CENTRAL CMPZ5240B L1: COILTRONICS CTX50-1 ZENER DIODE D4 PROVIDES AN UNDERVOLTAGE LOCKOUT, REDUCING THE INPUT CURRENT REQUIRED AT START-UP www.DataSheet4U.com ...
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... V = 24V IN 400 300 V = 12V IN 200 100 0 3.5 2 4.5 BATTERY VOLTAGE (V) 1934 TA07b LT1934/LT1934-1 www.DataSheet4U.com 10k 0.047 CHRG GATE 0.022 F LTC4052 ACPR SENSE BAT 350mA TIMER GND 1-CELL 4.2V TIMER Li-Ion 0.1 F BATTERY 1934 TA07a CHARGE STATUS AC PRESENT ...
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... LT1934/LT1934-1 U TYPICAL APPLICATIO S 15V TO 32V ON OFF 18 12V Step-Down Converter D2 0 BOOST 100 2.2 F LT1934 D1 SHDN FB GND C1: KEMET T495D226K020AS C2: TAIYO YUDEN GMK325BJ225MN D1: ON SEMI MBR0540 D2, D4: CENTRAL CMPD914 D3: CENTRAL CMPZ5234B 6.2V ZENER L1: TDK SLF6028T-101MR42 www.DataSheet4U.com D3 V OUT 12V 170mA ...
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... U S6 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636) 1.22 REF 1.50 – 1.75 2.80 BSC 1.4 MIN (NOTE 4) 0.95 BSC 0.80 – 0.90 1.00 MAX 0.09 – 0.20 (NOTE 3) LT1934/LT1934-1 www.DataSheet4U.com 2.90 BSC (NOTE 4) PIN ONE ID 0.30 – 0.45 6 PLCS (NOTE 3) 0.01 – 0.10 1.90 BSC S6 TSOT-23 0302 19 1934f ...
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... LT1934/LT1934-1 U TYPICAL APPLICATIO 6.5V TO 34V ON OFF RELATED PARTS PART NUMBER DESCRIPTION LT1616 25V, 500mA (I ), 1.4MHz, High Efficiency OUT Step-Down DC/DC Converter LT1676 60V, 440mA (I ), 100kHz, High Efficiency OUT Step-Down DC/DC Converter LT1765 25V, 2.75A (I ), 1.25MHz, High Efficiency OUT Step-Down DC/DC Converter LT1766 60V, 1. 200kHz, High Efficiency ...