UF2768

UF2768 UTC | Alldatasheet

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UNISONIC TECHNOLOGIES CO., LTD UF2768 Preliminary CMOS IC www.unisonic.com.tw 1 of 8 Copyright © 2018 Unisonic Technologies Co., Ltd QW-R140-012.a THREE-PHASE SINE-WAVE SENSOR-LESS FAN MOTOR DRIVER  DESCRIPTION The UF2768 provides all the circuitry for sensor-less speed control of three-phase brushless DC motor. The Sine-wave Driver Method will be better low-noise. The controller functions include start-up circuit, back-EMF commutation control, Pulse Width Modulation (PWM) speed c ontrol, lock protection, and thermal shutdown circuit. The UF2768 is suitable for both game machine and CPU cooler that need silent drivers.  FEATURES * Three-Phase class sin wave driver method * Three-Phase Full-Wave Sensor-Less Drive Method * Adjustable Forced Commutation Frequency (for Start-up) * Built-In External PWM Speed Control * Built-In Quick Start Function * FG (Rotation Speed Detection) Output * Soft Switching Circuit (for Noise Reducing) * Power Saving Function (PWM Duty Input is 0%) * Built-In Lock Protection and Auto Restart Function * Thermal Shutdown Circuit MSOP-10 DFN3030-10  ORDERING INFORMATION Ordering Number Lead Free Halogen Free Package Packing UF2768L-SM2-R UF2768G-SM2-R MSOP-10 Tape Reel UF2768L-K10-3030-R UF2768G-K10-3030-R DFN3030-10 Tape Reel

UF2768 Preliminary CMOS IC UNISONIC TECHNOLOGIES CO., LTD 2 of 8 www.unisonic.com.tw QW-R140-012 .a  MARKING MSOP-10 DFN3030-10  PIN CONFIGURATION 1FG COM VCC UO FR WO VO GND OSC PWM Top View DFN3030-10 FG PWM VCC GND COM OSC UO VO FR WO MSOP-10  PIN DESCRIPTION PIN No. PIN NAME Description 1 FG Rotation Speed Output. This is an open-drain output.

2 COM Motor Neutral Point Input Pin

3 V CC Supply Voltage Input Pin. 4 UO Driver Output Pin. Output signal for driving motor phase U. 5 FR Motor Spin Direction Control Pin. High Level Input: U → V → W Low Level Input: U → W → V 6 WO Driver Output Pin. Output signal for driving motor phase W. 7 VO Driver Output Pin. Output signal for driving motor phase V. 8 GND Ground Pin. 9 OSC Start-up Commutation Time Setting. Connect a capacitor to GND to set start-up commutation time. 10 PWM PWM Signal Input Pin. Input PWM signal to control rotation speed.

UF2768 Preliminary CMOS IC UNISONIC TECHNOLOGIES CO., LTD 3 of 8 www.unisonic.com.tw QW-R140-012 .a  BLOCK DIAGRAM VCC 3 UO4 VO7 FG1 PHASE SEL PWM Quick Sta OSC 9 FR 5 START UP COM2ZC Sensor LOGIC GND 8 WO

UF2768 Preliminary CMOS IC UNISONIC TECHNOLOGIES CO., LTD 4 of 8 www.unisonic.com.tw QW-R140-012 .a  ABSOLUTE MAXIMUM RATING PARAMETER SYMBOL RATINGS UNIT VCC Pin Supply Voltage V CC 7 V UO/VO/WO Pin Output Current I OUT 1 A UO/VO/WO Pin Output Voltage V UO/VVO/VWO 7 V FG Pin Output Voltage V FG 7 V FG Pin Sink Current IFG 10 mA FR Pin Input Voltage V FR 7 V MSOP-10 0.6 W Power Dissipation DFN3030-10 PD 1.05 W Junction Temperature T J -40 ~ +150 °C Storage Temperature T STG -65 ~ +150 °C Notes: 1. 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. 2. Stresses beyond those listed und er "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only and functiona l operation of the device at these or any other conditions beyond those indicated under "recom-mended operating conditions" is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.  THERMAL DATA PARAMETER SYMBOL RATINGS UNIT MSOP-10 208 °C/W Junction to Ambient (Note) DFN3030-10 θJA 119 °C/W Note: The data tested by surface mounted on a 2 inch2 FR-4 board with 2OZ copper.  ELECTRICAL CHARACTERISTICS (VCC=5V, TA=25°C, unless otherwise specified) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT SUPPLY CURRENT Operating Current I CC1 Rotation Mode 3.5 5 mA Standby Supply Current I CC2 PWM=0 100 150 μA PWM CONTROL PWM Input High Level Voltage V PWMH 2.5 V PWM Input Low Level Voltage V PWML 0.8 V PWM High Input Current I PWMH PWM=VCC 0 uA PWM Low Input Current IPWML PWM=GND -10 -20 uA PWM Input Frequency F PWM 2 50 KHZ OUTPUT DRIVERS Output Driver Saturation Voltage V O IOUT=250mA, Upper and Lower total 0.3 V FG Pin Low Voltage V FG F G=5mA 0.2 V FG Pin Leak Current I FGL V FG=7V 10 uA LOCK PROTECTION Lock Detection On Time T ON 1 Sec Lock Detection Off Time T OFF 5 Sec THERMAL SHUTDOWN Over Temperature Shutdown 160 °C Over Temperature Shutdown Hysteresis OTS 30 °C QUICK START Quick Start Enable Time T QS 16 mS

UF2768 Preliminary CMOS IC UNISONIC TECHNOLOGIES CO., LTD 5 of 8 www.unisonic.com.tw QW-R140-012 .a  FUNCTIONAL DESCRIPTION PWM Speed Control (Fixed-Frequency Output) It is possible to change rotation speed of the motor by switching output transistor. The on-duty of switching de-pends on the signal from input to PWM terminal. The output PWM frequency is fixed frequency.(30KHZ) (See Figure 1 PWM Input Waveform). Quick Start This IC disables the lock protection function when the PWM input keeps low level for more than 16ms. (See Figure

2 Quick Start Waveform)

The FG pin is an open-drain output, connecting a pull up resi stor to a high level voltage for the speed detection function. When WO pin voltage switches to high, the FG is high (switch off) and the WO pin voltage switches to low then FG is low (switch on). The FG output only works in sensor- less mode. (See Figure 3 FG Output Waveform)

UF2768 Preliminary CMOS IC UNISONIC TECHNOLOGIES CO., LTD 6 of 8 www.unisonic.com.tw QW-R140-012 .a  FUNCTIONAL DESCRIPTION (Cont.) Soft Switch (Sine-Wave Output) The is a soft switch function to make phase current be-co me more gentle, which can reduce the noise of motor in switching interval. Using PWM duty cycle control to creat e the sinusoidal current waveform. BEMF detection window is opened on phase W in order to measure the rotor position so as to define the modulation timing. close to the ideal sine wave output.( See figure 4. Sinusoidal PWM) Lock Protection and Automatic Restart The UF2768 provides the lock protection and automatic restart functions to prev ent the coil burnout while the fan is locked. As the fan is locked, the IC will come into st artup operation for 1 second. Then, the IC will switch to lock protection mode to close output driver for 6 seconds. After lock protection mode, the IC switches to startup operation again. If the locked condition still remains, the lock and restar t process will be recurred until the locked condition is released. Thermal Protection The UF2768 has thermal protection. When internal junction temperature reaches 160°C, the output devices will be switched off. When the IC’s junction temperature cools down 30°C, the thermal sensor will turn on the output devices again, resulting in a pulsed output during continuous thermal protection.

UF2768 Preliminary CMOS IC UNISONIC TECHNOLOGIES CO., LTD 7 of 8 www.unisonic.com.tw QW-R140-012 .a  APPLICATION INFORMATION Input Protection Diode & Capacitor It is necessary to add a protection diode (D1) to prevent the damage from the power reverse connection. However, the protection diode will cause a volt age drop on the supply voltage. The curr ent rating of the diode must be larger than the maximum output current. For the noise reducti on purpose, a capacitor (C1) is connected between V CC and GND. (see Typical Application Circuit) It’s suggested that C1 should be placed as close as possible in the VCC pin. OSC Capacitor The capacitor connects from OSC pin to GND can be determined the frequency of force commutation. The optimal design of the frequency could make sure the motor start- up in succeed. Its capacitance from 1000pF to 3300pF is recommended. FG Resistor The value of FG resistor could be decided by the following equation: CC FG/RD FG FG/RD V- VR= I For example: VCC=5V, IFG=5mA, VFG=0.2V, RFG=0.96kΩ The value of resistor in the range of 1kw to 10kw is recommended. Thermal Consideration Refer to “Maximum Power Dissipation vs. Ambient Temperature”, the IC is safe to operate below the curve and it will cause the thermal protection if the operating area is above the line. For example, T A= 75°C, the MSOP-10 package maximum power dissipation is about 0.48W. The power dissipation can be calculated by the following equation: DC C UO VO UO CC CC×I +VP= ( V - )V- × IV For example: VCC=5V, ICC=3mA, IOUT=250mA, VUO=4.85V, VVO=0.15V, then PD=0.09W The GND pin provides an electrical connection to the ground and channeling heat away. The printed circuit board (PCB) forms a heat sink and dissipates most of the heat into ambient air.

UF2768 Preliminary CMOS IC UNISONIC TECHNOLOGIES CO., LTD 8 of 8 www.unisonic.com.tw QW-R140-012 .a  TYPICAL APPLICATION CIRCUIT VO WO UO Pull High Voltage FGFR OSC PWM COM UF2768 2.2µF Cosc 2.2nF VIN GND VCC 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. UTC reserves the right to make changes to information published in this document, including without limitation specifications and product descriptions, at any time and without notice. This document supersedes and replaces all information supplied prior to the publication hereof.