Datasheet LTM4636 (Analog Devices) - 10

LTM4636
Decoupling requireMenTs TA = 25°C. Use Figure 1 configuration. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
CIN External Input Capacitor Requirement IOUT = 40A, 6 × 22µF Ceramic X7R Capacitors 100 µF (VIN = 4.70V to 16V, VOUT = 1.5V) (See Table 4) COUT External Output Capacitor Requirement IOUT = 40A (See Table 4) 1000 µF (VIN = 4.70V to 16V, VOUT = 1.5V)
operaTion Power Module Description
monitor feedback pin referred will attempt to protect the The LTM4636 is a high efficiency regulator that can provide output voltage in the event of an overvoltage >10%. The a 40A output with few external input and output capacitors. top MOSFET is turned off and the bottom MOSFET is This module provides precisely regulated output voltages turned on until the output is cleared. programmable via external resistors from 0.6V DC to 3.3V Pulling the RUNC pin below 1.1V forces the regulator con- DC over a 4.70V to 15V input range. The Typical Applica- troller into a shutdown state. The TRACK/SS pin is used for tion schematic is shown in Figure 20. programming the output voltage ramp and voltage tracking The LTM4636 has an integrated constant-frequency cur- during start-up. See the Applications Information section. rent mode regulator, power MOSFETs, 0.18µH inductor, The LTM4636 is internally compensated to be stable over protection circuitry, 5V regulator and other supporting all operating conditions. Table 5 provides a guideline for discrete components. The switching frequency range is input and output capacitances for several operating condi- from 250kHz to 770kHz, and the typical operating frequency tions. LTpowerCAD is available for transient and stability is 400kHz. For switching noise-sensitive applications, it analysis. This tool can be used to optimize the regulators can be externally synchronized from 250kHz to 800kHz, loop response. subject to minimum on-time limitations and limiting the A remote sense amplifier is provided for accurately sensing inductor ripple current to less than 40% of maximum output voltages at the load point. output current. Multiphase operation can be easily employed with the A single resistor is used to program the frequency. See internal clock source or a synchronization clock applied the Applications Information section. to the MODE/PLLIN input using an external clock source, With current mode control and internal feedback loop and connecting the CLKOUT pins. See the Applications compensation, the LTM4636 module has sufficient stabil- Information section. Review Figure 4. ity margins and good transient performance with a wide High efficiency at light loads can be accomplished with range of output capacitors, even with all ceramic output selectable Burst Mode operation using the MODE_PLLIN capacitors. An option has been provided for external loop pin. These light load features will accommodate battery compensation. LTpowerCAD® can be used to optimize operation. Efficiency graphs are provided for light load op- the external compensation option. See the Applications eration in the Typical Performance Characteristics section. Information section. A TEMP+ and TEMP– pins are provided to allow the internal Current mode control provides cycle-by-cycle fast current device temperature to be monitored using an onboard limit in an overcurrent condition. An internal overvoltage diode connected NPN transistor. 4636f 10 For more information www.linear.com/LTM4636 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Decoupling Requirements Operation Applications Information Typical Applications Package Description Package Photo Typical Application Design Resources Related Parts