Datasheet MAX25600 (Maxim) - 9

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Pin Description PIN NAME FUNCTION TQFN TSSOP
1 5 DH1 Top Gate Drive for Buck Section of the MAX25600. Drives the gate of the top n-channel MOSFET. 2 6 LX1 Buck-Side Switching Node. LX1 pin swings from a diode voltage drop below ground up to VIN. 3 7 DL1 Bottom Gate Drive for Buck Section of the MAX25600. Drives the gate of the bottom n-channel MOSFET. 4 8 PGND Power Ground Connection 5 9 DL2 Bottom Gate Drive for the Boost Section of the MAX25600. Drives the gate of the bottom n-channel MOSFET. 6 10 LX2 Switching Node of Boost Section of the MAX25600. LX2 pin swings from a diode voltage drop below ground up to VOUT. 7 11 DH2 Top Gate Drive for Boost Section of the MAX25600. Drives the gate of the top n-channel MOSFET. 8 12 BST2 High-Side Power Supply for High-Side Gate Drive for Boost Section. Connect a 0.1μF ceramic capacitor from BST2 to LX2. 9 13 CSP Positive Input to the Current-Sense Comparator for the Average-Current-Mode Controller 10 14 CSN Negative Input to the Current-Sense Comparator for the Average-Current-Mode Controller 11 15 ISP Positive LED Current-Sense Input. The voltage between ISP and ISN is proportionally regulated to 1.3V or (VICTRL - 0.2)/(5 x RCS_LED), whichever is less. 12 16 ISN Negative LED Current-Sense Input 13 17 DIMOUT External Dimming p-Channel MOSFET Gate Driver Overvoltage-Protection Input for the LED String. Connect a resistive divider between the output, FB, and GND. When the voltage on FB exceeds 1.23V, a fast-acting comparator immediately stops PWM switching and pulls DIMOUT high to disconnect the LED string from the output. 14 18 FB (R V FB1 + RFB2) OVP = 1.23 RFB2 15 19 FLT Active-Low, Open-Drain Fault Indicator Output. See the Fault Indicator (FLT) section. 16 20 COMP Compensation-Network Connection. For proper compensation, connect a suitable RC network from COMP to SGND. 17 21 SGND Signal Ground Connection 18 22 V 5V Regulator Output. Connect a minimum 2.2μF ceramic capacitor from VCC to SGND for CC stable operation. 19 23 SS Soft-Start Pin. A minimum 10nF capacitor is recommended on this pin. www.maximintegrated.com Maxim Integrated │ 9