Rainbow Electronics MAX15046B - Manual (Page 8)

40V, High-Performance, Synchronous
Buck Controller
MAX15046
8 ______________________________________________________________________________________
Pin Description
PIN NAME FUNCTION
1 IN
Regulator Input. Connect to the input rail of the buck converter. Bypass IN to PGND with a 100nF
minimum ceramic capacitor. When operating in the 5V Q10% range, connect IN to V
CC .
2 V CC
5.25V Linear Regulator Output. Bypass V CC to PGND with a ceramic capacitor of at least 4.7FF
when V CC supplies MOSFET gate-driver current at DRV or 2.2FF when V CC is not used to power
DRV.
3 PGOOD
Open-Drain Power-Good Output. Pull up PGOOD to an external power supply or output with an
external resistor.
4 EN
Active-High Enable Input. Pull EN to GND to disable the buck converter output. Connect to V CC
for always-on operation. EN can be used for power sequencing and as a UVLO adjustment input.
5 LIM
Current-Limit Input. Connect a resistor from LIM to GND to program the current-limit threshold from
30mV (R
LIM = 6kI) to 300mV (R LIM = 60kI).
6 COMP Error-Amplifier Output. Connect compensation network from COMP to FB or from COMP to GND.
7 FB
Feedback Input (Inverting Input of Error Amplifier). Connect FB to a resistive divider between the
buck converter output and GND to adjust the output voltage from 0.6V up to 0.85 x IN.
8 RT
Oscillator-Timing Resistor Input. Connect a resistor from RT to GND to set the oscillator frequency
from 100kHz to 1MHz.
9 GND Analog Ground. Connect PGND and AGND together at a single point.
10 PGND Power Ground. Use PGND as a return path for the low-side MOSFET gate driver.
11 DRV
Gate-Driver Supply Voltage. DRV is internally connected to the low-side driver supply. Bypass DRV to
PGND with a 2.2FF minimum ceramic capacitor (see the Typical Application Circuits).
12 DL Low-Side External MOSFET Gate-Driver Output. DL swings from DRV to PGND.
13 BST
Boost Flying Capacitor Connection. Internally connected to the high-side driver supply. Connect a
ceramic capacitor of at least 100nF between BST and LX and a diode between BST and DRV for
the high-side MOSFET gate-driver supply.
14 LX
Inductor Connection. Also serves as a return terminal for the high-side MOSFET driver current.
Connect LX to the switching side of the inductor.
15 DH High-Side External MOSFET Gate-Driver Output. DH swings from BST to LX.
16 CSP Current-Sense Positive Input. Connect to the drain of low-side MOSFET with Kelvin connection.
— EP
Exposed Pad. EP is internally connected to ground. Connect EP to a large copper ground plane to
maximize thermal performance.