POWER LOSS (W) LTC3315A Dual 5V, 2A Synchronous Step-Down DC/DCs in Tiny LQFN and WLCSP FEATURES DESCRIPTION n Dual Outputs Each with 2A Output Current The LTC 3315A features dual 2A monolithic synchronous n High Efficiency: 19m NMOS and 75m PMOS step-down converters operating from a 2.25V to 5.5V n Wide Bandwidth, Fast Transient Response input supply in one package for space-constrained appli- n Switching Frequency Synchronizable Up to 3MHz cations with demanding performance requirements. Using n V Range: 2.25V to 5.5V constant frequency, peak current mode control at switch- IN n V Range: 0.5V to V ing frequencies up to 3MHz with a minimum on-time as OUT IN n V Accuracy: 1% low as 25ns, both bucks achieve high efficiency and fast OUT n Low Ripple Burst Mode Operation transient response in a very small applicationfootprint. n Peak Current Mode Control The LTC3315A operates in forced continuous or pulse- n Minimum On-Time: 25ns skipping mode for low noise or in Burst Mode opera- n Safely Tolerates Inductor Saturation in Overload tion for high efficiency at light loads. The common buck n Shutdown Current: 1.2A switching frequency is 2MHz and can be synchronized to n Precision 400mV Enable Thresholds an external oscillator via the MODE/SYNC pin. n Internal Soft-Start and Compensation n The LTC3315A can regulate outputs as low as 500mV. Power Good Output n Other features include precision enable thresholds, a Low Profile, Thermally Enhanced 12-Lead PGOOD signal, output overvoltage protection, thermal 2mm 2mm 0.74mm LQFN and 16-Ball 1.64mm shutdown, output short-circuit protection, and up to 100% 1.64mm 0.5mm WLCSP Packages n duty cycle operation for low dropout. The LTC3315A is AEC-Q100 Qualified for Automotive Applications available in a compact 2mm 2mm LQFN package and a 1.64mm 1.64mm WLCSP package. APPLICATIONS All registered trademarks and trademarks are the property of their respective owners. n Servers, Telecom Supplies, Optical Networking n Distributed DC Power Systems (POL) n FPGA, ASIC, P Core Supplies n Industrial/Automotive/Communications TYPICAL APPLICATION Efficiency vs Load Current Dual 2MHz 2A Buck Regulators 100 1.0 880nH 90 0.9 V V IN OUT1 V SW1 IN 1.2V, 2A 2.25V TO 5.5V 0.8 80 6.8pF 10F 140k 33F 70 0.7 FB1 60 0.6 EN1 100k LTC3315A 50 0.5 V Burst Mode OPERATION IN 1H 40 0.4 V V = 3.3V, V = 1.2V OUT2 IN OUT 10F SW2 1.8V, 2A L = 880nH, L DCR = 19m 30 0.3 4.7pF 261k f = 2MHz SW EN2 22F 20 0.2 EFFICIENCY MODE/SYNC FB2 10 0.1 POWER LOSS 100k PGOOD GND 0 0 1m 10m 100m 1 2 3315A TA01a f = 2MHz SW LOAD CURRENT (A) 3315A TA01b Rev. B 1 Document Feedback For more information www.analog.com EFFICIENCY (%)LTC3315A ABSOLUTE MAXIMUM RATINGS (Note 1) V ............................................................... 0.3V to 6V Operating Junction Temperature (Notes 2, 3): IN EN1, EN2 .............. 0.3V to Lesser of (V + 0.3V) or 6V LTC3315AA ........................................ 40C to 125C IN FB1, FB2 ............... 0.3V to Lesser of (V + 0.3V) or 6V LTC3315AE ........................................ 40C to 125C IN MODE/SYNC ........ 0.3V to Lesser of (V + 0.3V) or 6V LTC3315AI ......................................... 40C to 125C IN PGOOD ......................................................... 0.3V to 6V LTC3315AJ ........................................ 40C to 150C I ......................................................................5mA LTC3315AH ........................................ 40C to 150C PGOOD LTC3315AMP ..................................... 55C to 150C Storage Temperature Range .................. 65C to 150C Maximum Reflow (Package Body) Temperature ...260C PIN CONFIGURATION TOP VIEW TOP VIEW 1 2 3 4 A MODE/SYNC 12 11 PGOOD FB2 FB1 EN1 1 10 V IN B FB1 2 9 GND V EN2 EN1 GND IN 13 GND C FB2 3 8 GND SW2 SW2 SW1 SW1 D EN2 4 7 V IN 5 6 V GND GND V IN IN WLCSP PACKAGE CB-16-11 16-BALL (1.64mm 1.64mm 0.5mm) LQFN PACKAGE 12-LEAD (2mm 2mm 0.74mm) T = 125C, = 58C/W, = 2.7C/W, JMAX JA JCTOP = 14.8C/W, = 2.1C/W, = 15C/W T = 150C, = 51C/W, = 8.6C/W, JB JT JB JMAX JA JCBOTTOM AND VALUES DETERMINED PER JESD51-7 ON A JEDEC 2S2P PC = 80C/W, = 12C/W, = 0.8C/W, JCTOP JB JT AND VALUES DETERMINED PER JESD51-7 ON A JEDEC 2S2P PC EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB Rev. B 2 For more information www.analog.com PGOOD MODE/SYNC SW2 SW1