Datasheet LT8630 (Analog Devices) - 8

LT8630
pin FuncTions VIN (Pin 1):
The VIN pin powers the internal control circuitry
VOUT (Pin 12):
The VOUT pin is the output to the internal and is monitored by an undervoltage lockout comparator. sense resistor that measures current flowing in the in- The VIN pin is also connected to the drain of the on chip ductor. Connect the output capacitor from the VOUT pin power switch. The VIN pin has high dI/dt edges and must to the GND pin. be decoupled to the GND pin of the device. The input
NC13 (Pin 13):
No Internal Connection. Leave this pin decouple capacitor should be placed as close as possible open or connect to GND. to the VIN and GND pins.
IND (Pin 14):
The IND pin is the input to the internal sense
EN/UV (Pin 3):
The EN/UV pin is used to enable the LT8630 resistor that measures current flowing in the inductor. or to program the undervoltage lockout threshold with external resistors. The LT8630 is in shutdown mode( IQ
NC15 (Pin 15):
No Internal Connection. Leave this pin < 5µA) when the EN/UV pin voltage is below 1.18V and open or connect to GND. active mode when the voltage exceeds 1.18V. Tie EN/UV
INTV
to the V
CC (Pin 16):
The INTVCC pin is the bypass pin for the IN pin if the EN/UV feature isn’t required. internal 3V regulator. Connect a 2.2µF bypass capacitor
PG (Pin 5):
The PG pin is an open drain output that sinks from the INTVCC pin to the GND pin. Do not load the INTVCC current when the feedback voltage deviates from the regula- pin with external circuitry. tion point by ±7.5%. The PG pin has 1.6% of hysteresis.
BST (Pin 18):
The BST pin is used to provide a drive
NC6 (Pin 6):
No Internal Connection. Leave this pin open voltage, higher than the VIN voltage, to the topside power or connect to GND. switch. Place a 0.1µF capacitor between the BST and SW pins as close as possible to the device.
DNC (Pin 7):
Do Not Connect. Do not connect this pin, allow it to float.
SW (Pin 20):
The SW pin is the output of the internal power switches. Place the inductor and BST capacitor as close
RT (Pin 8):
A 8.66k resistor must be connected between as possible to keep the SW PCB trace short. the RT pin and GND. The RT resistor sets an internal clock reference. Do not leave pin floating.
GND (Exposed Pad Pin 21):
The exposed pad GND pin is the ONLY GROUND CONNECTION for the device. The
NC9 (Pin 9):
No Internal Connection. Leave this pin open exposed pad should be soldered to a large copper area or connect to GND. to reduce thermal resistance. The GND pin also serves as
TR/SS (Pin 10):
A capacitor with a minimum value of 100pF small signal ground. For ideal operation all small signal must be connected between the TR/SS pin and the GND ground paths should connect to the GND pin at a single pin. The voltage ramp rate on the TR/SS pin determines point avoiding any high current ground returns. the output voltage ramp rate. This pin can also be used for voltage tracking. Do not leave this pin floating.
FB (Pin 11):
The FB pin is the negative input to the er- ror amplifier. The output switches to regulate this pin to 0.808V with respect to the GND pin. 8630f 8 For more information www.linear.com/LT8630 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts