NX4110

NX4110 1A SYNCHRONOUS BUCK SWITCHER WITH FET ON BOARD PRODUCTION DATA SHEET Pb Free Product DESCRIPTION FEATURES n n n n SOT23-5L package Internal Digital Soft Start Internally-compensated Current mode controller Peak Current Limit with HICCUP Feature and Over Temperature Protection Prebias Start-up Operation Pgood Available Pb-free and RoHS compliant The NX4110 is a current mode PWM buck switcher with internal compensation, can provide up to 1A output current with FET on board. It operates from 2.8V to 5.5V and output as low as 0.6V which is ideal for the application with single cell Li-Ion battery as well as other 3.3V input bus supply applications. Switching frequency is n fixed 1MHz, small surface mount inductors and capaci- n tors are allowed to use, make it good for portable appli- n cations. NX4110 is available in 5-pin SOT23 package. n n n n APPLICATIONS Li-Ion battery operated portable system Cellular Phones Portable applications USB Devices TYPICAL APPLICATION VIN=5V 5 FB VIN SW GND 4 3 2 22uF(X5R,6.3V) 1 PGOOD Fig.1 - Typical application of NX4110CZ1TR NX4110 2.2uH Vout=2.5V 10uF (X5R, 6.3V) 332k 105k ORDERING INFORMATION Device NX4110CZ1TR Temperature -40oC to 85oC Package SOT23-5L Pb-Free Yes Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 1 NX4110 ABSOLUTE MAXIMUM RATINGS VIN to GND ..................................................................... -0.3V to 6V SW,FB,PGOOD to GND .................................................. -0.3V to VIN + 0.3V ESD Susceptibility ............................................................. 1kV Lead Temperature(Soldering,10sec.) .................................... 300oC Storage Temperature Range ................................................ -55oC to 150oC Operating Junction Temperature Range ................................ -40oC to 150oC CAUTION: Stresses above those listed in "ABSOLUTE MAXIMUM RATINGS", 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 5-LEAD PLASTIC SOT23 θJA ≈ 110o C/W PGOOD 1 GND 2 SW 3 5 FB 4 VIN ELECTRICAL SPECIFICATIONS VIN=3.5V. Typical data refers to TA= 25oC. Unless otherwise specified. PARAMETER Reference Voltage Ref Voltage Line Regualtion Line Regulation VIN UVLO VIN Rising Threshold VIN Falling Threshold Supply Voltage(VIN) VIN Input Voltage Range Quiescent Current Oscillator (Rt) Frequency Max Duty Cycle Min ON time Error Amplifiers Feedback Input Bias Current SS Soft Start time Rev. 2.0 12/30/09 SYM VFB Test Condition Min 0.59 TYP 0.6 2 MAX 0.607 Units V mV VIN=3V to 5V,VOUT=1.8V, IOUT=10mA 2.3 2.5 2.3 2.8 V V VIN Iq FS No Load, switching 2.8 4 800 78 1000 86 100 5.5 V mA 1200 kHz % nS 0.05 Tss 500 uA uS Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 2 NX4110 PARAMETER Current Limit Current Limit Threshold Thermal Shutdown Thermal shutdown trip point Hysteresis Internal Switch Rdson of Control FET Rdson of Synchronous FET PGOOD PGOOD low Threshold voltage high Threshold PGOOD voltage SYM Test Condition Min TYP 1.8 155 15 Vin=5V Vin=3.3V Vin=5V Vin=3.3V 400 480 300 360 85 90 MAX Units A o o C C mohm mohm %VREF %VREF PIN DESCRIPTIONS PIN SYMBOL SW PIN DESCRIPTION SW output. Junction of the internal high-side and low-side power MOSFETs, and output inductor. Ground Connection for Chip. Connect GND with large copper areas to the input and output supply returns, and negative terminals of the input and output capacitors. Error amplifier inverting input. Error amplifier inverting input. This pin is connected via resistor dividers to the output of the switching regulators to set the output DC voltage. A 332kohm resistor is recommended to be connected from VOUT and FB . Supply voltage input for switcher. This pin needs minimum 22uF/X5R/6.3V as input capacitor. PGOOD indicator. It requires a pull up resistor to Vcc or lower voltage. When FB pin reaches 90% of the reference voltage PGOOD transitions from LO to HI state. GND FB VIN PGOOD Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 3 NX4110 BLOCK DIAGRAM Thermal Shutdown POR POR VIN CLK VIN start Soft start Hiccup timer OSC one shot S R Q + UVLO Vref Bias Generator 3 cycle counter OCPB + - Vref PWM FB PWM comparator OCPB POR VIN PGOOD SS_finished FB 0.9*Vref GND Control Logic SW Fig. 2 - Simplified block diagram of the NX4110 Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 4 NX4110 Typical Operating Characteristics R e ference voltage vs tem p e rature 0.604 0.603 0.602 Reference voltage(V) 0.601 0 .6 0.599 0.598 0.597 0.596 0.595 0.594 0.593 0 20 40 60 80 temperature(°C ) 100 120 140 160 Fig.3 - Reference volateg vs temperature Normalized frequency vs temperature 1 Normalized Frequency 0.98 0.96 0.94 0.92 0.9 0 20 40 60 80 100 120 140 160 temperature(°C) Fig.4 - Normalized frequency vs temperature Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 5 NX4110 D u ty C y c l e v s M a x i m u m O u tp u t C u r r e n t 1200 Output Current (mA) 1000 800 600 400 200 0 0 20 40 D u ty c y c l e ( % ) 60 80 Fig.5 - Duty cycle vs maximum output current Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 6 NX4110 Typical Application( VOUT=2.5V) VIN=5V 5 FB VIN SW GND 4 3 2 22uF(X5R,6.3V) 1 PGOOD Fig. 6 - Demo board schematic NX4110 2.2uH Vout=2.5V 10uF (X5R, 6.3V) 332k 105k Fig. 7 - Output ripple Fig. 8 - Transient response Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 7 NX4110 Typical Application( VOUT=1.8V) VIN=5V 5 FB VIN SW GND 4 3 2 22uF(X5R,6.3V) 1 PGOOD Fig. 9 - Demo board schematic NX4110 2.2uH Vout=1.8V 10uF (X5R, 6.3V) 332k 165k Fig. 10 - Output ripple Fig. 11 - Transient response Fig. 12 - Efficiency Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 8 NX4110 Typical Application( VOUT=1.2V) VIN=5V 5 FB VIN SW GND 4 3 2 22uF(X5R,6.3V) 1 PGOOD Fig. 13 - Demo board schematic NX4110 2.2uH Vout=1.2V 10uF (X5R, 6.3V) 332k 332k Fig. 14 - Output ripple Fig. 15 - Transient response Fig. 16 - Startup Rev. 2.0 12/30/09 Fig. 17 - Shutdown Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 9 NX4110 Typical Application( VOUT=1.2V) Fig. 18 - Efficiency Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 10 NX4110 Demoboard Layout Fig. 19 - Demoboard schematic Fig. 20- Top layer Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 11 NX4110 Fig. 21 - Gound layer Fig. 22 - Power layer Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 12 NX4110 Fig. 23 - Bottom layer Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 13 NX4110 SOT23 5 PIN PACKAGE OUTLINE DIMENSIONS Top View Side View Rev. 2.0 12/30/09 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 14