UNISONIC TECHNOLOGIES CO., LTD UCS1201 Preliminary LINEAR INTEGRATED CIRCUIT LOW VOLTAGE SYNCHRONOUS BUCK CONTROLLER DESCRIPTION The UTC UCS1201 is a low voltage buck controller. It provides the control for a DC-DC power solution producing an output voltage as low as 0.980V over a wide current range. The UTC UCS1201 operates at a default switching frequency of 200kHz, but switching frequency is user-programmable with an additional resistor between ROSC and ground. This device provides undervoltage lockout protection, soft-start, and is assembled in an SOP-8 package. SOP-8 FEATURES * 0.980V±1.0% reference voltage * 200ns transient response * soft-start * 200kHz oscillator frequency (No external resistor required) * UVLO * OVP through synchronous MOSFETs * Synchronous N-Channel buck design ORDERING INFORMATION Ordering Number Lead Free Halogen Free UCS1201L-S08-R UCS1201G-S08-R UCS1201L-S08-T UCS1201G-S08-T www.unisonic.com.tw Copyright © 2013 Unisonic Technologies Co., Ltd Package Packing SOP-8 SOP-8 Tape Reel Tube 1 of 5 QW-R103-066.a UCS1201 Preliminary PIN CONFIGURATION PIN DESCRIPTION PIN NO. 1 2 3 4 5 6 7 8 PIN NAME VCC ROSC NC COMP GATE(H) GATE(L) VFB GND LINEAR INTEGRATED CIRCUIT DESCRIPTION Power supply input. Frequency adjust pin. No connect. Error amp output. High-side switch FET driver pin. Low-side synchronous FET driver pin. Feedback voltage Ground BLOCK DIAGRAM VCC - UVLO + Latch + - 8.5V/7.5V - COMP + + - 0.25V Error Amp VFB - - + PWM Comp Driver + GATE(H) Latch + - 0.98V GATE(L) NC + 0.465V Σ Oscillator 200kHz GND UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw Frequency Adjust ROSC 2 of 5 QW-R103-066.a UCS1201 Preliminary LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATING PARAMETER SYMBOL RATINGS UNIT Operating Junction Temperature TJ 150 °C Storage Temperature Range TSTG -65~150 °C Notes: 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 Junction to Case SYMBOL θJA θJC RATINGS 165 48 UNIT °С/W °С/W MAXIMUM RATING PARAMETER SYMBOL VMAX VMIN ISOURCE VCC 20V -0.5V N/A COMP VFB ROSC 6.0V 6.0V 6.0V High-Side FET Driver GATE(H) 20V Low-Side FET Driver GATE(L) 20V -0.5V -0.5V -0.5V -0.5V, -2.0V for 50ns -0.5V, -2.0V for 50ns GND 0.5V 10mA 1.0mA 1.0mA 1.5A Peak, 200mA DC 1.5A Peak, 200mA DC 1.5A Peak, 450mA DC IC Power Input Compensation Capacitor Voltage Feedback Input Frequency Adjust Ground UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw -0.5V ISINK 1.5A Peak, 450mA DC 10mA 1.0mA 1.0mA 1.5A Peak, 200mA DC 1.5A Peak, 200mA DC N/A 3 of 5 QW-R103-066.a UCS1201 Preliminary LINEAR INTEGRATED CIRCUIT ELECTRICAL CHARACTERISTICS (0°C<TJ<125°C, 9.0V<VCC<20V, CGATE(H)=CGATE(L)=3.3nF, CCOMP=0.1μF, ROSC=74kΩ, unless otherwise specified.) (Note 1) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT Error Amplifier VFB Bias Current IFB VFB=0V 0.4 2.0 μA COMP Source Current ISOURCE COMP=1.5V, VFB=0.8V 15 30 60 μA COMP Sink Current ISINK COMP=1.5V, VFB=1.2V 15 30 60 μA COMP=VFB 0.970 0.980 0.990 V Reference Voltage VREF TJ<25°C 0.965 0.980 0.995 V COMP Max Voltage VCOMP-MAX VFB=0.8V 2.4 3.1 V COMP Min Voltage VCOMP-MIN VFB=1.2V 0.1 0.2 V COMP Fault Discharge ICHARGE COMP=1.2V, VCC=6.9V 0.5 1.2 mA Current at UVLO COMP Fault Discharge VRESET 0.1 0.25 0.3 V Threshold to Reset UVLO GATE(H) and GATE(L) Rise Time tR 1.0V<GATE(L), GATE(H)<VCC-2.0V, VCC=12V 40 80 ns Fall Time tF VCC-2.0V<GATE(L), GATE(H)<1.0V, VCC=12V 40 80 ns GATE(H) to GATE(L) tDH GATE(H)<2.0V, GATE(L)>2.0V 40 60 105 ns Delay GATE(L) to GATE(H) tDL GATE(L)<2.0V, GATE(H)>2.0V 40 60 105 ns Delay Minimum Pulse Width tPULSE GATE(X)=4.0V 250 ns Measure GATE(L) or GATE(H) VCC-0.5 VCC High Voltage (AC) VH V 0.5nF<CGATE(H)=CGATE(L)<10nF, (Note 2) Measure GATE(L) or GATE(H) 0 0.5 V Low Voltage (AC) VL 0.5nF<CGATE(H)=CGATE(L)<10nF, (Note 2) PWM Comparator VFB=0V, Increase COMP Until GATE(H) Starts 0.415 0.465 0.525 V PWM Comparator Offset VPWM-MIN Switching Ramp Max Duty Cycle 80 % Artificial Ramp Duty Cycle=50%, ROSC=74kΩ 50 63 75 mV Transient Response COMP=1.5V, VFB 20mV Overdrive. (Note 2) 200 300 ns VFB Input Range (Note 3) 0 1.4 V Oscillator 170 200 230 kHz FOSC ROSC Not Used Switching Frequency FOSC ROSC=74kΩ 240 280 320 kHz General Electrical Specifications VCC Supply Current IQ COMP=0V (No Switching) 9.0 12 mA Start Threshold GATE(H) Switching, COMP Charging 8.0 8.5 9.0 V Stop Threshold GATE(H) Not Switching, COMP Discharging 7.0 7.5 8.0 V Hysteresis VHYS Start-Stop 0.75 1.0 1.25 V Notes:1.Characteristics at temperature extremes are guaranteed via correlation using quality statistical control methods. 2.Guaranteed by design. Not tested in production. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 of 5 QW-R103-066.a UCS1201 Preliminary LINEAR INTEGRATED CIRCUIT TYPICAL APPLICATION CIRCUIT 12V L1 1.0µH D3 BAS20HT1 C1 + 1000µF/16V D2 BAV99LT1 R1 470 C11 Q3 MMBT3904LT1 0.1µF D1 18V Zener BZX84C18V C3 0.1µF U1 VCC C4 1.0µF ROSC NC COMP R3 Opition + C2 1000µF/16V GND 2.5V/10A C9 0.01µF Q1 VFB UT60N03 GATE(L) GATE(H) L2 4.7µH UTC UCS1201 + Q2 C11 0.1µF 1000µF*2 UT110N03 R5 0.98V 104 R6 3.32k 5.11k C10 4700pF 5V 12V 33µF UT65N03 1.4µH 1.2V/10A UTC UCS1201 VCC GND ROSC NC COMP VFB 1000pF UT65N03 2.26k GATE(L) GATE(H) 56µF option 0.1µF 0.1µF 10k 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 5 of 5 QW-R103-066.a