Datasheet LTM4626 (Analog Devices) - 6

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PIN FUNCTIONS PACKAGE ROW AND COLUMN LABELING MAY VARY TRACK/SS (E2):
Output Tracking and Soft-Start Pin of the
AMONG µModule PRODUCTS. REVIEW EACH PACKAGE
Switching Mode Regulator. Allows the user to control the
LAYOUT CAREFULLY.
rise time of the output voltage. Putting a voltage below
VOUT (A1-A5, F3, G1-G3):
Power Output Pins of the 0.6V on this pin bypasses the internal reference input Switching Mode Regulator. Apply output load between to the error amplifier, instead it servos the FB pin to the these pins and GND pins. Recommend placing output TRACK voltage. Above 0.6V, the tracking function stops decoupling capacitance directly between these pins and and the internal reference resumes control of the error GND pins. See the Applications Information section for amplifier. There’s an internal 6µA pull-up current from paralleling outputs. INTVCC on this pin, so putting a capacitor here provides
COMPb (F1):
Internal Loop Compensation Network. soft-start function. See the Applications Information sec- Connect to COMPa to use the internal compensation in tion for details. majority of applications.
MODE/CLKIN (D2):
Discontinuous Mode Select Pin and
FREQ (E1):
Switching Frequency Program Pin. Frequency External Synchronization Input to Phase Detector. Tie is set internally to 600kHz. An external resistor can be MODE/CLKIN to GND for discontinuous mode of opera- placed from this pin to GND to increase frequency, or from tion. Floating MODE/CLKIN or tying it to a voltage above this pin to INTV 1V will select forced continuous mode. Furthermore, con- CC to reduce frequency. See the Applications Information section for frequency adjustment. necting MODE/CLKIN to an external clock will synchronize the system clock to the external clock and puts the part
COMPa (D1):
Current control threshold and error ampli- in forced continuous mode. See Applications Information fier compensation point of the switching mode regulator section for details. channel. The internal current comparator threshold is
–
linearly proportional to this voltage. Tie the COMPa pins
VOSNS (C2):
Negative Input to the Differential Remote from different channels together for parallel operation. Sense Amplifier. Connect an external resistor between FB – The device is internal compensated. Connect to COMPb and VOSNS pin to set the output voltage of the specific to use the internal compensation. Or connect to a Type-II channel. See the Applications Information section for C-R-C network to use customized compensation. details.
FB (C1):
The Negative Input of the Error Amplifier for
CLKOUT (F2):
Output Clock Signal for PolyPhase the switching mode regulator. This pin is internally con- Operation. The phase of CLKOUT with respect to CLKIN nected to V + is determined by the state of the respective PHMODE pin. OSNS with a 60.4kΩ precision resistor. Output voltages can be programmed with an additional resistor CLKOUT’s peak-to-peak amplitude is INTVCC to GND. See between FB and V – Applications Information section for details. OSNS pins. In PolyPhase® operation, tying the FB pins together allows for parallel operation.
VIN (D3-D4, E3-E4, F4, G4):
Power input pins connect to See the Applications Information section for details. the drain of the internal top MOSFET and signal VIN to the
V +
internal 3.3V regulator for the control circuitry for each
OSNS (B1):
Positive Input to the Differential Remote Sense Amplifier. Internally, this pin is connected to FB switching mode regulator channel. Apply input voltages with a 60.4k 0.5% precision resistor. See the Applications between these pins and GND pins. Recommend placing Information section for details. input decoupling capacitance directly between each of VIN pins and GND pins.
PHMODE (G5):
Control Input to the Phase Selector of the Switching Mode Regulator. Determines the phase rela-
INTVCC (B3):
Internal 3.3V Regulator Output of the tionship between internal oscillator and CLKOUT. Tie it to Switching Mode Regulator Channel. The internal power INTV drivers and control circuits are powered from this voltage. CC for 2-phase operation, tie it to SGND for 3-phase operation, and tie it to INTV Decouple each pin to GND with a minimum of 2.2µF local CC/2 for 4-phase operation. See Applications Information section for details. low ESR ceramic capacitor. Rev B 6 For more information www.analog.com Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Electrical Characteristics Pin Configuration Typical Performance Characteristics Pin Functions Block Diagram Decoupling Requirements Operation Applications Information Package Description Revision History Package Photo Design Resources Related Parts