UNISONIC TECHNOLOGIES CO., LTD USR1051 Preliminary LINEAR INTEGRATED CIRCUIT 3 A SYNCHRONOUS BUCK REGULATOR DESCRIPTION The UTC USR1051 is a high efficiency, 3A synchronous buck regulator. The UTC USR1051 works from 5V to 23V input voltage range, and provides up to 3A of continuous output current with an output voltage adjustable down to 0.8V. The UTC USR1051 comes in an exposed pad HSOP-8 package and is rated over a -40°C~+85°C operating ambient temperature range. HSOP-8 FEATURES * Synchronous Buck * 5V~23V operating input voltage range * High efficiency * Internal soft start * Output voltage adjustable to 0.8V * 3A continuous output current * Cycle-by-cycle current limit * 400kHz PWM operation * Pre-bias start-up * Thermal shutdown * Short-circuit protection * Exposed pad HSOP-8 package ORDERING INFORMATION Ordering Number Lead Free Halogen Free USR1051L-SH2-T USR1051G-SH2-T USR1051L-SH2-R USR1051G-SH2-R www.unisonic.com.tw Copyright © 2013 Unisonic Technologies Co., Ltd Package Packing HSOP-8 HSOP-8 Tube Tape Reel 1 of 4 QW-R103-065.b USR1051 Preliminary PIN CONFIGURATION PIN DESCRIPTION PIN NO. 1 2 3 4 5 6 7 8 Exposed pad PIN NAME PGND VIN AGND FB COMP EN NC NC LX LINEAR INTEGRATED CIRCUIT DESCRIPTION Power ground Supply voltage input Analog ground Feedback input External loop compensation pin Enable pin No Connect Pin. No Connect Pin. Switching node BLOCK DIAGRAM VIN EN Start Up VREF REF_0.8V FB EA Current Source Bias SENSE OSC SLOPE Driver PWM PWM LATCH Dead Time Control LX Driver COMP UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw AGND PGND 2 of 4 QW-R103-065.b USR1051 Preliminary LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATING PARAMETER SYMBOL RATINGS UNIT Supply Voltage VIN 23 V LX to AGND -0.7~VIN+0.3 V LX to AGND (20ns) -5~22 V EN to AGND -0.3~VIN+0.3 V FB, SS, COMP to AGND -0.3~6.0 V PGND to AGND -0.3~+0.3 V Ambient Temperature TA -40~+85 °C Junction Temperature TJ +150 °C Storage Temperature TSTG -65~+150 °C Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. THERMAL DATA PARAMETER Junction to Ambient (Note 2) SYMBOL θJA UNIT °C/W RATINGS 5~23 0.8~0.85×VIN UNIT V V RECOMMENDED OPERATING CONDIIONS PARAMETER SYMBOL VIN VOUT Supply Voltage Output Voltage RATING 50 ELECTRICAL CHARACTERISTICS (Note 3) (TA=25°C, VIN=VEN=12V, VOUT=3.3V, unless otherwise specified) PARAMETER Supply Voltage Supply Current (Quiescent) Shutdown Supply Current Feedback Voltage Load Regulation Line Regulation Feedback Voltage Input Current EN Input Threshold SS Time MODULATOR Frequency Maximum Duty Cycle Controllable Minimum On Time Current Sense Transconductance Error Amplifier Transconductance PROTECTION Current Limit SYMBOL TEST CONDITIONS VIN IIN IOUT=0, VFB=1.2V, VEN>2V IOFF VEN=0V VFB TA=25 °C MIN 5 0.788 TYP 3.5 1 0.8 0.5 1 IFB VEN Off Threshold On Threshold CSS=16nF fO DMAX TMIN 2 2 380 85 450 MAX UNIT 23 V 5 mA 10 µA 0.812 V % % 200 nA 0.6 V V ms 550 150 7 180 kHz % ns A/V µA/V 3.5 4.5 A TJ Rising 150 °C Over-Temperature Shutdown Limit 100 °C TJ Falling Notes: 1. Devices are inherently ESD sensitive, handling precautions are required. Human body model rating: 1.5 kΩ in series with 100pF. 2. The value of θJA is measured with the device mounted on a 1-in2 FR-4 board with 2oz. Copper, in a still air environment with TA=25°C. The value in any given application depends on the user’s specific board design. 3. Specification in BOLD indicate an ambient temperature range of -40°C~+85°C. These specifications are guaranteed by design. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 3 of 4 QW-R103-065.b USR1051 Preliminary LINEAR INTEGRATED CIRCUIT TYPICAL APPLICATION CIRCUIT UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 of 4 QW-R103-065.b