Datasheet LTC3861 (Analog Devices) - 10
| Manufacturer | Analog Devices |
| Description | Dual, Multiphase Step-Down Voltage Mode DC/DC Controller with Accurate Current Sharing |
| Pages / Page | 38 / 10 — pin FuncTions VINSNS (Pin 34):. TRACK/SS1 (Pin 35), TRACK/SS2 (Pin 11):. … |
| File Format / Size | PDF / 996 Kb |
| Document Language | English |
pin FuncTions VINSNS (Pin 34):. TRACK/SS1 (Pin 35), TRACK/SS2 (Pin 11):. CONFIG (Pin 33):. VCC (Pin 36):
Model Line for this Datasheet
Text Version of Document
LTC3861
pin FuncTions VINSNS (Pin 34):
VIN Sense Pin. Connects to the VIN
TRACK/SS1 (Pin 35), TRACK/SS2 (Pin 11):
Combined power supply to provide line feedforward compensation. Soft-Start and Tracking Inputs. For soft-start operation, A change in VIN immediately modulates the input to the connecting a capacitor from this pin to ground will control PWM comparator and changes the pulse width in an in- the voltage ramp at the output of the power supply. An versely proportional manner, thus bypassing the feedback internal 2.5μA current source will charge the capacitor and loop and providing excellent transient line regulation. An thereby control an extra input on the reference side of the external lowpass filter can be added to this pin to prevent error amplifier. For tracking operation, this input allows the noisy signals from affecting the loop gain. start-up of a secondary output to track a primary output
CONFIG (Pin 33):
Line Feedforward Configuration Pin. according to a ratio established by a resistor divider from This pin allows the user to configure the multiplier to the primary output to the secondary error amplifier track achieve accurate modulator gain over varying V pin. For coincident tracking of both outputs at start-up, IN and switching frequencies. This pin can be connected to V a resistor divider with values equal to those connected CC or SGND. An internal resistor will pull this pin to SGND to the secondary VSNSP pin from the secondary output when it is floated. should be used to connect the secondary track input from the primary output. This pin is internally clamped to 1.2V, and is used to communicate over current events in a master-slave configuration.
VCC (Pin 36):
Chip Supply Voltage. Bypass this pin to GND with a capacitor (0.1µF to 1µF ceramic) in close proximity to the chip. 3861fb 10 For more information www.linear.com/LTC3861 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Related Parts
pin FuncTions VINSNS (Pin 34):
VIN Sense Pin. Connects to the VIN
TRACK/SS1 (Pin 35), TRACK/SS2 (Pin 11):
Combined power supply to provide line feedforward compensation. Soft-Start and Tracking Inputs. For soft-start operation, A change in VIN immediately modulates the input to the connecting a capacitor from this pin to ground will control PWM comparator and changes the pulse width in an in- the voltage ramp at the output of the power supply. An versely proportional manner, thus bypassing the feedback internal 2.5μA current source will charge the capacitor and loop and providing excellent transient line regulation. An thereby control an extra input on the reference side of the external lowpass filter can be added to this pin to prevent error amplifier. For tracking operation, this input allows the noisy signals from affecting the loop gain. start-up of a secondary output to track a primary output
CONFIG (Pin 33):
Line Feedforward Configuration Pin. according to a ratio established by a resistor divider from This pin allows the user to configure the multiplier to the primary output to the secondary error amplifier track achieve accurate modulator gain over varying V pin. For coincident tracking of both outputs at start-up, IN and switching frequencies. This pin can be connected to V a resistor divider with values equal to those connected CC or SGND. An internal resistor will pull this pin to SGND to the secondary VSNSP pin from the secondary output when it is floated. should be used to connect the secondary track input from the primary output. This pin is internally clamped to 1.2V, and is used to communicate over current events in a master-slave configuration.
VCC (Pin 36):
Chip Supply Voltage. Bypass this pin to GND with a capacitor (0.1µF to 1µF ceramic) in close proximity to the chip. 3861fb 10 For more information www.linear.com/LTC3861 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Related Parts
