BD95700MUV ROHM Electronics, BD95700MUV Datasheet
BD95700MUV
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BD95700MUV Summary of contents
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... Controllers for Graphic Card BD95700MUV ●Description BD95700MUV phase switching regulator controller with high output current which can achieve low output voltage (0.4V ~ 3.3V) from AC/ 12V. High efficiency for the switching regulator can be realized by utilizing an external N-MOSFET power transistor. A new technology called H load change without phase compensation capacitance and resistance ...
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... BD95700MUV ●ELECTRICAL CHARACTERISTICS (Unless otherwise noted, Ta=25℃, VCC=5V, VIN=12V, REF=1.2V, RT=100kΩ) Parameter Symbol [Total Block] Vcc Bias Current Vcc Standby Current [5Vcc Block] 5Vcc Output Voltage 5Vcc 5Vcc Output Current I [UVLO Block] VCC Threshold Voltage Vcc_UVLO VCC Hysteresis Voltage dVcc_UVLO ...
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... BD95700MUV ●Block Diagram VIN_BUS=12V BUSEN 5 VCCDRV 21 VCC 22 5VCC 3 REFIN/EN 0.6V 15 AGND 4 DROOP IMAX/IOUT 10 PGND IREFOUT /POK 16 www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. OFF 8VReg Controller BG 3ms 5VReg Soft Start Reg Vo Comp Controller 4.5V CS1+ CS1- Current Sense OCP ...
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... BD95700MUV ●Pin Configuration SW2 LG2 VCCDRV VCC LG1 SW1 ●Pin Function Table PIN No. PIN Name 1 UG1 2 BT1 3 5VCC 4 AGND 5 BUSEN 6 CS1+ 7 CS1- 8 CS2- 9 CS2+ 10 IMAX / IOUT DROOP PGND 15 REFIN INREFOUT/ POK 17 BT2 18 UG2 19 SW2 20 LG2 21 VCCDRV 22 VCC 23 LG1 ...
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... This pin has multiple functions such as the output current indication, OCP (Over Current Protection) limit setting, and the output voltage load line adjustment pin. BD95700MUV detects the voltage between Cs+ pin and Cs- pin and limits the output current (OCP) using resistance connected between IMAX/IOUT/Droop and GND. A very low current sense resistor or inductor DCR can also be used for this platform. ・ ...
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... BD95700MUV ●Explanation of Operation The BD95700MUV is a synchronous buck regulator controller incorporating ROHM’s proprietary H drops due to a rapid load change, the system quickly restores V control system. When V OUT interval. Thus, it serves to improve the regulator’s transient response Reg control (Normal operation) ...
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... BD95700MUV ●Timing Chart ・Soft Start Function REFIN VOUT IIN ・Output Over Voltage Protection REF x 1 Switching ・Short Circuit Protection with Timer Latch REF x 0.5 FB TSCP SCP REFIN/UVLO www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. Soft start is activated when REF hits its enabling threshold (VCC, 5VCC, and BUSEN have to be beyond their own UVLO thresholds) ...
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... BD95700MUV ●External Component Selection 1. Inductor (L) selection ΔIL VIN IL VOUT L Co Output Ripple Current ※Passing a current larger than the inductor’s rated current will cause magnetic saturation in the inductor and decrease system efficiency. In selecting the inductor, be sure to allow enough margin to assure that peak current does not exceed the inductor rated current value. ※ ...
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... BD95700MUV 4.MOSFET Selection VIN main switch VOUT L Co synchronous switch 5. OCP Setting Resistance VIN_BUS CS1+ CS1- OCP CS2+ CS2- V IMAX IMAX PIN I IMAX R IMAX 6. DROOP setting Resistance VIN_BUS CS1+ CS1- CS2+ DROOP PIN CS2 DROOP DROOP www ...
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... BD95700MUV 7. Setting output voltage The output voltage is REFIN = VOUT when VOUT is tied to the FB directly. The range of VOUT is 0.4V ~ 3.3V. BUSEN 3 H Reg CONTROLLA REFIN FB The output voltage is calculated as follows when resistor divider network is connected between the FB and VOUT. REFIN set 5Vcc. The range of Vout is 0.6～3.3V ...
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... BD95700MUV 9. UVLO BD95700MUV has function to detect input UVLO voltage in each VCC, 5VCC, and BUSEN for output voltage to start up. If all these inputs go beyond their own UVLO threshold voltage, the soft start function kicks in. These threshold voltages have their own hysteresis voltage to avoid faulty operation caused by input noises and glitchs. ...
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... BD95700MUV 11. Vout small Ripple Voltage VIN Resistor R3 and capacitor C (=56pF)are needed to stabilize switching operation when Vout ripple voltage is less than 20mV. The values of R1, R2 and R3 are determined as in the formula (20) below R1+R2 ≦ 20kΩ,10×R1 ≦ R3 ・・・(20) www.rohm.com © ...
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... BD95700MUV ●Reference Data VOUT REFIN BUSEN VCC Fig1.Sequence VOUT REFIN BUSEN VCC Fig4.Sequence VOUT(100mV/div) HG1,HG2(10V/div） IOUT (20A/div) Fig7.Load Transient Response (VCC=12V) VOUT(100mV/div) HG1,HG2(10V/div） IOUT (20A/div) Fig10.Load Transient Response (VCC=5V) www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. VOUT REFIN ...
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... BD95700MUV ●Reference Data VOUT SW1, SW2 LG1 Fig13.Continuos MODE (VCC=5V) VOUT SW1 BUSEN Fig16.SCP Function REFIN VOUT SW1, SW2 Fig19.Reference Function IL1, IL2 SW1, SW2 Fig22.Current balance (Io=20A) www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. VOUT SW1, SW2 LG1 Fig14.Continuos MODE ...
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... BD95700MUV BD95700MUV Evaluation Board Circuit with 5V Drive (VCC=5V input , VIN=3.3~12V input , REFIN=5VCC, Vout=1.2V ) ■ ■ VIN 3.3V ~ 12V C3 U1 BUSEN BD95700MUV_VQFN24 PGND 5 BUSEN VCCDRV 5V VCC C25 22 VCC VCC5 C7 3 5VCC REFIN SW1 15 REFIN AGND C18 4 AGND AGND DROOP R7 12 DROOP ...
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... BD95700MUV BD95700MUV Evaluation Board Circuit with 8V Drive (VIN=10.8~13.2V input , REFIN=5VCC, Vout=1.2V ) ■ ■ VIN 3.3V ~ 12V C3 U1 BUSEN BD95700MUV_VQFN24 PGND 5 BUSEN VCCDRV VCC C25 22 VCC VCC5 C7 3 5VCC REFIN SW1 15 REFIN AGND C18 4 AGND AGND DROOP R7 12 DROOP IOUT ...
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... BD95700MUV BD95700MUV Evaluation Board Circuit with 12V Drive ( VIN=12V input, VCC=12V input, REFIN=5VCC, Vout=1.2V ) ■ ■ VIN 12V C3 BUSEN PGND 5 BUSEN VCCDRV VCC C25 22 VCC VCC5 C7 3 5VCC REFIN SW1 15 REFIN AGND C18 4 AGND AGND DROOP R7 12 DROOP ...
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... Do not continue to use the IC after operating this circuit or use the environment where the operation of this circuit is assumed. TSD on temperature [°C] (typ.) BD95700MUV 10. Testing on application boards When testing the application board, connecting a capacitor to a pin with low impedance subjects the IC to stress. ...
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... BD95700MUV 11. Regarding input pin of the IC This monolithic IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them isolated. P-N junctions are formed at the intersection of these P layers with the N layers of other elements, creating a parasitic diode or transistor. For example, the relation between each potential is as follows: When GND > ...
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... BD95700MUV ●Type Designations (Selections) for Ordering Part No. Part No. VQFN024V4040 4.0±0.1 1PIN MARK S 0.08 S 2.4±0.1 C0 0.75 +0.05 0.25 -0.04 0.5 www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved Package MUV : VQFN024V4040 <Tape and Reel information> Tape Embossed carrier tape ...
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