link to page 12 link to page 12 link to page 12 link to page 12 LTM4650 PIN FUNCTIONS (Recommended to Use Test Points to Monitor Signal Pin Connections.) RUN1, RUN2 (F5, F9): Run Control Pin. A voltage above INTVCC (H8): Internal 5V Regulator Output. The control 1.25V will turn on each channel in the module. A voltage circuits and internal gate drivers are powered from this below 1.25V on the RUN pin will turn off the related chan- voltage. Decouple this pin to PGND with a 4.7µF low ESR nel. Each RUN pin has a 1µA pull-up current, once the tantalum or ceramic. INTVCC is activated when either RUN pin reaches 1.2V an additional 4.5µA pull-up current RUN1 or RUN2 is activated. is added to this pin. TEMP (J6): Temperature Monitor. An internal diode con- DIFFOUT (F8): Internal Remote Sense Amplifier Output. nected NPN transistor between this pin and SGND with Connect this pin to VOUTS1 or VOUTS2 depending on which 10nF filtering capacitor. See the Applications Information output is using remote sense. In parallel operation con- section. nect one of the VOUTS pin to DIFFOUT for remote sensing. EXTVCC (J7): External power input that is enabled through SW1, SW2 (G2, G11): Switching node of each channel a switch to INTVCC whenever EXTVCC is greater than 4.7V. that is used for testing purposes. Also an R-C snubber Do not exceed 6V on this input, and connect this pin to network can be applied to reduce or eliminate switch node VIN when operating VIN on 5V. An efficiency increase will ringing, or otherwise leave floating. See the Applications occur that is a function of the (VIN – INTVCC) multiplied Information section. by power MOSFET driver current. Typical current require- PHASMD (G4): Connect this pin to SGND, INTV ment is 30mA. V CC, or IN must be applied before EXTVCC, and floating this pin to select the phase of CLKOUT to 60 EXTVCC must be removed before VIN. degrees, 120 degrees, and 90 degrees respectively. VIN (M2-M11, L2-L11, J2-J4, J9-J11, K2-K4, K9-K11):CLKOUT (G5): Clock output with phase control using the Power Input Pins. Apply input voltage between these pins PHASMD pin to enable multiphase operation between and GND pins. Recommend placing input decoupling devices. See the Applications Information section. capacitance directly between VIN pins and GND pins. PGOOD1, PGOOD2 (G9, G8): Output Voltage Power Good Heat Sink (Top Exposed Metal): The top exposed metal Indicator. Open drain logic output that is pulled to ground is electrically unconnected. when the output voltage is not within ±10% of the regula- tion point. Rev. C For more information www.analog.com 9 Document Outline Description Typical Application Absolute Maximum Ratings Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Operation Applications Information Related Parts Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Simplified Block Diagram Decoupling Requirements Operation Applications Information Typical Applications Package Description Revision History Package Photo Design Resources Related Parts