LT3690 LINER [Linear Technology], LT3690 Datasheet
LT3690
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LT3690 Summary of contents
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FEATURES n Wide Input Voltage Range: 3.4V to 42V Ultralow Quiescent Current Burst Mode n 2.5μA I Regulating 12V to 3. Output Ripple < 10mV P-P n High Efficiency Synchronous Operation: 96% Efficiency at 1A, 5V OUT 94% ...
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LT8610 ABSOLUTE MAXIMUM RATINGS (Note EN/UV, PG ..........................................................42V IN BIAS ..........................................................................30V BST Pin Above SW Pin................................................4V FB, TR/SS, RT, INTV . ..............................................4V CC SYNC Voltage . ............................................................6V Operating Junction Temperature Range (Note 2) LT8610E ................................................. –40 to ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER CONDITIONS Oscillator Frequency Top Power NMOS On-Resistance I SW Top Power NMOS Current Limit Bottom Power NMOS On-Resistance V INTVCC Bottom Power NMOS Current ...
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LT8610 TYPICAL PERFORMANCE CHARACTERISTICS Efficiency at 5V OUT 100 700kHz 12V 24V 0.5 1 1.5 2 LOAD CURRENT (A) 8610 ...
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TYPICAL PERFORMANCE CHARACTERISTICS No Load Supply Current 5 3.3V OUT 4.5 IN REGULATION 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0 INPUT VOLTAGE (V) 8610 G10 Top FET ...
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LT8610 TYPICAL PERFORMANCE CHARACTERISTICS Dropout Voltage 800 700 600 500 400 300 200 100 0 0 0.5 1 1.5 2 2.5 LOAD CURRENT (A) 8610 G19 Minimum Load to Full Frequency (SYNC DC High) 100 OUT f ...
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TYPICAL PERFORMANCE CHARACTERISTICS RT Programmed Switching Frequency 250 225 200 175 150 125 100 0.2 0.6 1 1.4 1.8 SWITCHING FREQUENCY (kHz) 8610 G27 Bias Pin Current BIAS OUT ...
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LT8610 TYPICAL PERFORMANCE CHARACTERISTICS Transient Response I LOAD 1A/DIV V OUT 200mV/DIV 50μs/DIV 8610 G36 50mA TO 1A TRANSIENT 12V , 5V IN OUT C = 47μF OUT PIN FUNCTIONS SYNC (Pin 1): External Clock Synchronization Input. Ground this pin ...
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PIN FUNCTIONS BIAS (Pin 14): The internal regulator will draw current from BIAS instead of V when BIAS is tied to a voltage higher IN than 3.1V. For output voltages of 3.3V and above this pin should be tied to ...
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LT8610 OPERATION The LT8610 is a monolithic, constant frequency, current mode step-down DC/DC converter. An oscillator, with frequency set using a resistor on the RT pin, turns on the internal top power switch at the beginning of each clock cycle. ...
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APPLICATIONS INFORMATION Achieving Ultralow Quiescent Current To enhance efficiency at light loads, the LT8610 operates in low ripple Burst Mode operation, which keeps the out- put capacitor charged to the desired output voltage while minimizing the input quiescent current and ...
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LT8610 APPLICATIONS INFORMATION FB Resistor Network The output voltage is programmed with a resistor divider between the output and the FB pin. Choose the resistor values according to: ⎛ ⎞ V OUT ⎝ ⎜ ⎠ ⎟ R1= R2 – 1 ...
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APPLICATIONS INFORMATION The LT8610 is capable of a maximum duty cycle of greater than 99%, and the V -to-V dropout is limited by the IN OUT R of the top switch. In this mode the LT8610 skips DS(ON) switch cycles, ...
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LT8610 APPLICATIONS INFORMATION current. This allows use of a physically smaller inductor, or one with a lower DCR resulting in higher efficiency. Be aware that low inductance may result in discontinuous mode operation, which further reduces maximum load current. For ...
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APPLICATIONS INFORMATION A final precaution regarding ceramic capacitors concerns the maximum input voltage rating of the LT8610. As previously mentioned, a ceramic input capacitor combined with trace or cable inductance forms a high quality (un- derdamped) tank circuit. If the ...
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LT8610 APPLICATIONS INFORMATION Output Power Good When the LT8610’s output voltage is within the ±9% window of the regulation point, which the range of 0.883V to 1.057V (typical), the output voltage is considered good and the open-drain ...
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APPLICATIONS INFORMATION LT8610 EN/UV GND Figure 3. Reverse V Protection IN PCB Layout For proper operation and minimum EMI, care must be taken during printed circuit board layout. Figure 4 shows the recommended component placement ...
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LT8610 TYPICAL APPLICATIONS 5V Step-Down Converter BST IN 5.5V TO 42V 4.7μF EN/UV SW LT8610 SYNC BIAS 10nF TR/SS PG 1μF FB INTV CC RT GND PGND 18. 2MHz SW 5V Step-Down Converter V IN ...
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PACKAGE DESCRIPTION Please refer to http://www.linear.com/designtools/packaging/ 2.845 0.102 (.112 .004) 5.23 (.206) MIN 0.305 0.038 (.0120 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE ...
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... PART NUMBER DESCRIPTION LT8611 42V, 2.5A, 96% Efficiency, 2.2MHz Synchronous Micropower Step-Down DC/DC Converter with I = 2.5μA and Input/Output Current Limit/Monitor Q LT3690 36V with 60V Transient Protection, 4A, 92% Efficiency, 1.5MHz Synchronous Micropower Step-Down DC/DC Converter with I LT3971 38V, 1.2A, 2.2MHz High Efficiency Micropower Step-Down DC/DC Converter with I = 2.8μA ...