LT1611 Linear Technology, LT1611 Datasheet
LT1611
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LT1611 Summary of contents
Page 1
... No load quiescent current of the LT1611 is 3mA, while in shutdown quiescent current drops to 0.5 A. The 36V switch allows V differential 33V. The LT1611 is available in the 5-lead SOT-23 package. , LTC and LT are registered trademarks of Linear Technology Corporation. L1B ...
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... Note 3: Current limit guaranteed by design and/or correlation to static test. Slope compensation reduces current limit at higher duty cycle INFORMATION ORDER PART NUMBER TOP VIEW LT1611CS5 4 SHDN S5 PACKAGE S5 PART MARKING LTES = 125 C, = 256 C/W JA unless otherwise noted. IN MIN TYP MAX ...
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... SHDN PIN VOLTAGE (V) No-Load Operating Quiescent Current vs Temperature* 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 100 –50 – TEMPERATURE ( C) LT1611 NFB Pin Bias Current vs Temperature 100 –50 – TEMPERATURE ( C) 1611 G02 Switch Current Limit vs Duty Cycle SHDN 900 800 ...
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... As load current is decreased, the switch turns on for a shorter period each cycle. If the load current is further decreased, the converter will skip cycles to maintain output voltage regulation. The LT1611 can work in either of two topologies. The C simpler topology appends a capacitive level shift ...
Page 5
... It is almost impossible to get rid of this noise, once present in the ground plane. The solution is to tie D1’s cathode to the ground pin of the LT1611 before the combined cur- rents are dumped into the ground plane as drawn in Figures 4, 5 and 6. This single layout technique can . virtually eliminate high frequency “ ...
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... SWX D1 Q1 tions due to load steps and output ripple voltage to very low levels. To illustrate, Figure 7 shows an LT1611 invert- ing converter with resistor loads R connected across the output, while R externally via a pulse generator. Output voltage wave- forms are pictured in subsequent figures, illustrating the performance of output capacitor type and the effect of C connected across R1 ...
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... R2 10k C1: AVX TAJB226M010 C2: TAIYO YUDEN LMK212BJ105MG C3: SEE TEXT D1: MBR0520 L1A, L1B: SUMIDA CLS62-220 Figure 7. Switching R Provides 50mA to 150mA L2 Load Step for LT1611 5V to – 5V Converter V OUT 50mV/DIV AC COUPLED 150mA LOAD CURRENT 50mA 100 s/DIV Figure 8. Load Step Response of LT1611 with 22 F Tantalum Output Capacitor ...
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... P–P copper at D1’s cathode is essential to obtain the low noise achieved in Figures 11 and 12’s oscillographs. Input bypass capacitor C1 should be placed close to the LT1611 as shown. The load should connect directly to output capacitor C2 for best load regulation. You can tie the local ground into the system ground plane at C3’s ground terminal ...
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... R2 10k C1: AVX TAJB226M010 C2: TAIYO YUDEN LMK212BJ105MG V C3: TAIYO YUDEN JMK325BJ226MM (1210 SIZE) OUT D1: MBR0520 L1: SUMIDA CLS62-220 OR 2 MURATA LQH3C220 (UNCOUPLED) and C at SHDN Pin Provide Soft-Start to LT1611 Inverting Converter SS V 2V/DIV 200mA/DIV 5V/DIV 1611 F15 Reaches Figure 16. R OUT – 2.1ms; Input Current Peaks at 240mA ...
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... LT1611 U OPERATIO Output Current The LT1611 will deliver 150mA at – 5V from a 5V 10% input supply higher voltage supply is available, more output current can be obtained. Figure 17’s schematic shows how to get more current. Although the LT1611’s maximum voltage allowed 10V, the SW pin can IN handle higher voltage (up to 36V) ...
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... Some capacitor types appropriate for use with the LT1611 are listed in Table 2. Diodes A Schottky diode is recommended for use with the LT1611. The Motorola MBR0520 is a very good choice. Where the input to output voltage differential exceeds 20V, use the MBR0530 ( a 30V diode). If cost is more important than efficiency, a 1N4148 can be used, but only at low current loads ...
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... LT1611 U TYPICAL APPLICATIO S 4-Cell to –10V Inverting Converter C2 L1A LT1611 68.1k SHUTDOWN SHDN NFB GND 10k C1: AVX TAJB226M010 (803) 946-0362 C2: TAIYO YUDEN LMK212BJ105MG C3: AVX TAJA685M016 D1: MOTOROLA MBR0520 (800) 441-2447 L1: SUMIDA CL562-150 (847) 956-0666 PACKAGE DESCRIPTION 2.60 – 3.00 (0.102 – 0.118) 1.50 – ...