NX2124CSTR Microchip

Evaluation board available. NX2124/2124A 300kHz SYNCHRONOUS PWM CONTROLLER PRODUCTION DATA SHEET Pb Free Product FEATURES DESCRIPTION n Bus voltage operation from 2V to 25V The NX2124/2124A controller IC is a synchronous Buck n Fixed 300kHz voltage mode controller controller IC designed for step down DC to DC con- n Internal Digital Soft Start Function verter applications. It is optimized to convert bus volt- n Prebias Startup ages from 2V to 25V to outputs as low as 0.8V voltage. n Less than 50 nS adaptive deadband The NX2124/2124A operates at fixed 300kHz, employs n Current limit triggers hiccup by sensing Rdson of fixed loss-less current limiting by sensing the Rdson of Synchronous MOSFET synchronous MOSFET followed by hiccup feature. n No negative spike at Vout during startup and NX2124A has higher current limit threshold than NX2124. shutdown Feedback under voltage also triggers hiccup. n Pb-free and RoHS compliant Other features of the device are: 5V gate drive, Adaptive deadband control, Internal digital soft start, Vcc APPLICATIONS undervoltage lock out and shutdown capability via the n Graphic Card on board converters comp pin. n Memory Vddq Supply in mother board applications n On board DC to DC such as 5V to 3.3V, 2.5V or 1.8V n Hard Disk Drive n Set Top Box TYPICAL APPLICATION L2 1uH Vin +5V C4 C5 Cin 100uF 1uF 280uF R5 D1 18mohm MBR0530T1 10 C3 5 1 1uF C6 Vcc BST 0.1uF M1 2 Hdrv 7 COMP M3 L1 1.5uH HI=SD Vout R4 8 SW 37.4k +1.8V 9A Co C7 R1 2 x (1500uF,13mohm) 27pF M2 4 C2 4k Ldrv 2.2nF 6 R2 FB C1 10k Gnd 4.7nF 3 R3 8k Figure1 - Typical application of 2124 ORDERING INFORMATION Device Temperature Package Frequency OCP Threshold Pb-Free o NX2124CSTR 0 to 70 C SOIC-8L 300kHz 360mV Yes o NX2124ACSTR 0 to 70 C SOIC-8L 300kHz 540mV Yes Rev.1.9 1 06/12/12 NX2124NX2124/2124A ABSOLUTE MAXIMUM RATINGS(NOTE1) Vcc to GND & BST to SW voltage ................... 6.5V BST to GND Voltage ...................................... 40V SW to GND Voltage .......................................-3V to 35V o o Storage Temperature Range ............................. -65 C to 150 C o o Operating Junction Temperature Range ............. -40 C to 125 C NOTE1: Stresses above those listed inABSOLUTE MAXIMUM RATING, may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. PACKAGE INFORMATION 8-PIN PLASTIC SOIC (S) o /130 CW JA BST 1 8 SW HDrv 2 7 Comp Gnd 3 6 Fb LDrv 4 5 Vcc ELECTRICAL SPECIFICATIONS o Unless otherwise specified, these specifications apply over Vcc = 5V, and T = 0 to 70 C. Typical values refer to T A A o = 25 C. Low duty cycle pulse testing is used which keeps junction and case temperatures equal to the ambient temperature. PARAMETER SYM Test Condition Min TYP MAX Units Reference Voltage Ref Voltage V 4.5V<Vcc<5.5V 0.8 V REF Ref Voltage line regulation 0.4 % Supply Voltage(Vcc) V Voltage Range V 5 V 4.5 5.5 CC CC V Supply Current (Static) I (Static) Outputs not switching 3 mA CC CC V Supply Current I C =3300pF F =300kHz 5 mA CC CC LOAD S (Dynamic) (Dynamic) Supply Voltage(V ) BST V Supply Current (Static) I (Static) Outputs not switching 0.15 mA BST BST V Supply Current I C =3300pF F =300kHz 5 mA BST BST LOAD S (Dynamic) (Dynamic) Under Voltage Lockout V -Threshold V _UVLO V Rising 4.2 V CC CC CC V -Hysteresis V _Hyst V Falling 0.22 V CC CC CC Rev.1.9 2 06/12/12