Datasheet LTM4633 (Analog Devices) - 10

LTM4633
operaTion Power Module Description
overvoltage is cleared. There are two temperature moni- The LTM4633 µModule regulator is a high performance tors in the LTM4633. TEMP1 monitors the close relative triple output nonisolated switching mode DC/DC power temperature of channels 1 and 2, and TEMP2 monitors supply. It can provide 10A per output with a few exter- the close relative temperature of channels 2 and 3. The nal input and output capacitors. This module provides two diode connected PNP transistors are grounded in the precisely regulated output voltages programmable via module and can be used as general purpose temperature external resistors from 0.8V DC to 1.8V DC (V monitors using a device that is designed to monitor the OUT1 and V single-ended connection. OUT2), and 0.8V DC to 5.5V DC (VOUT3) over a 2.375V to 16V input range with control bias on the CNTL_PWR Pulling any of the RUN pins below 1.3V forces the cor- pin, or 4.7V to 16V with control bias tied to VIN. When responding regulator channel into a shutdown state. The applying control bias in the range from 4.7V to 5.5V, then TK/SS pins are used for programming the output voltage connect the bias to CNTL_PWR and INVTCC, otherwise ramp and voltage tracking during start-up for each of the if >5.5V only bias the CNTL_PWR pin. The typical applica- channels. See the Applications Information section. tion schematic is shown in Figure 16. The LTM4633 is internally compensated to be stable over all The LTM4633 has three integrated constant-frequency operating conditions. Table 5 provides a guideline for input current mode regulators, power MOSFETs, power induc- and output capacitances for several operating conditions. tors, and other supporting discrete components. The The LTpowerCAD™ software tool is provided for transient typical switching frequency is 750kHz. For switching and stability analysis. The VFB pin is used to program the noise-sensitive applications, it can be externally syn- output voltage with a single external resistor to ground. chronized from 600kHz to 750kHz. See the Applications Each of the channels, operate with a 120° phase shift for Information section. multiphase operation. VOUT1 and VOUT2 can be combined With current mode control and internal feedback loop to provide a single 20A output. The two channels will compensation, the LTM4633 module has sufficient stabil- not be operating 180° phase shift, but 120° phase when ity margins and good transient performance with a wide combined for a 20A design. So the input RMS current range of output capacitors, even with all ceramic output will be higher than a 180° phase shifted design. See the capacitors. Applications Information section. Current mode control provides cycle-by-cycle fast current High efficiency at light loads can be accomplished with limit in an overcurrent condition. An internal overvolt- selectable Burst Mode operation using the MODE/PLLIN age monitor protects the output voltages in the event pin. These light load features will accommodate battery of an overvoltage >7.5%. The top MOSFET is turned off operation. Efficiency graphs are provided for light load op- and the bottom MOSFET is turned on until the output eration in the Typical Performance Characteristics section. 4633f 10 For more information www.linear.com/LTM4633 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Related Parts