BD9853AFV-E2 Rohm Semiconductor, BD9853AFV-E2 Datasheet
BD9853AFV-E2
Specifications of BD9853AFV-E2
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BD9853AFV-E2 Summary of contents
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... Step-down Switching Regulator(Controller type) BD9853AFV ●Description The BD9853AFV is a 2-ch synchronous DC/DC controller that can operate at a maximum switching frequency of 2MHz, enabling the use of a smaller external coil than conventional lower-frequency switching regulators. This makes the BD9853AFV a suitable choice for downsizing applications. ...
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... BD9853AFV ●Electrical Characteristics (Unless otherwise specified Ta=25℃,Vcc=12V,fosc=1000kHz,STB=3V) Parameter 【Whole Device】 Standby Current Circuit Current 【Regulator for Driver REGA】 Output Voltage Output Current Capability 【Regulator for Driver REGB】 Output Voltage Output Current Capability 【Oscillator】 Oscillator Frequency ...
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... BD9853AFV ●Electrical Characteristics (Unless otherwise specified, Ta=25℃,Vcc=12V,fosc=1000kHz,STB=3V) Parameter Symbol 【FET Driver】 RonP On Resistance (OUT1H) RonN RonP On Resistance (OUT1L) RonN RonP On Resistance (OUT2H) RonN RonP On Resistance (OUT2L) RonN Dead Time(Turn ON) tdtON Dead Time(Turn OFF) tdtOFF 【Control Block】 Threshold Voltage ...
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... BD9853AFV ●Characteristic Data 100 OUTL OUTH 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 FB VOLTAGE:VFB[V] Fig.1 FB VOLTAGE VS ON DUTY -10 -11 -12 -13 -14 -15 -16 -17 -18 -19 -20 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 4 4.2 4.4 FB VOLTAGE[V] Fig ...
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... BD9853AFV ●Block Diagram VCC VCC FB1 VOUT1 INV1 SCP/SOFT1 FB2 VOUT2 INV2 SCP/SOFT2 RT www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. both channel ON/OFF REGA 5V REGA REGB VCC-5V REGB VREF SOFT1 TSD VCC REGA ⊿ ｔ 0.8V REGB (Push-Pull) GND 0.56V ...
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... BD9853AFV ●Pin Configuration ●Pin Description Pin Number Pin Name 1 VCC 2 OUT1H 3 OUT1L 4 REGA FB1 7 INV1 8 SCP/SOFT1 9 SCP/SOFT2 10 INV2 11 FB2 12 GND 13 STB 14 OUT2L 15 OUT2H 16 REGB www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. Fig. 10 Pin Descriptions Input Supply Voltage High Side (Main) FET Driver Output Pin (CH1) ...
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... BD9853AFV ●Block functional descriptions ・Triangular wave oscillator Connecting the resistor that sets the triangular wave oscillation frequency at the RT terminal generates the triangular wave, which is input into the CH1 and CH2 PWM comparator. ・Error amp The INV pin detects the output voltage, compares it to the programmed output voltage and amplifies the difference for output by the FB pin. (The 0.8V reference is the comparison voltage. The tolerance is 1.25%.) ・ ...
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... BD9853AFV ●Timing Chart STB STB ON Vo1(solid line) INV1 (dotted line) SCP/SOFT1 0.3V Vo2 (solid line) INV2 (dotted line) SCP/SOFT2 0.3V www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. Output OFF at SCP/SOFT<0.3V 0.8V External GND short 1.3V (independent control) Sort removed 0.8V 1 ...
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... T iming Res nce(k Ω) Selecting the external MOSFET In the BD9853AFV design, the main side (OUT1H, OUT2H) is provided with an external PCH FET, while an NCH FET is used on the synchronous rectification side (OUT1L, OUT 2L) . FET selection should be made in conformance with the following relative configurations for maximum drain voltage (VDSS), maximum gate source voltage (VGS), maximum output current, on-resistance RDS (ON) and gate capacitance (Ciss) loss: ・ ...
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... BD9853AFV Selecting the synchronous diode An extremely low forward voltage Schottky barrier diode should be employed as the synchronous diode. Selection of the specific diode to be used should be made in conformance with the following relative configurations for maximum forward current, reverse voltage and diode power dissipation. ...
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... BD9853AFV Setting the Short Circuit Protection (SCP) delay time When the soft start is complete for each channel, the output voltage stabilizes at the set value 1.35V(typ) for the SCP/SOFT1, 2 pins. When any type of short circuit occurs, the voltage at the point of the fault is reduced. In this case, when voltage at the INV pin falls to 0 ...
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... BD9853AFV ●I/O Equivalent Circuit OUT1H(2),OUT2H(15) Max ratings：7V(from VCC or REGB REGB RT(5) Max ratings：7V REGA VCC RT SCP/SOFT1(8),SCP/SOFT2(9) Max ratings：7V REGA VREF VCC SCP/SOFT1 SCP/SOFT2 www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. OUT1L(3),OUT2L(14) Max ratings：7V ...
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... BD9853AFV ●Recommended Board Patterns P MOS MOS SBD There are two current loops at the behavior of switching regulator. When laying a pattern on the board, put these elements near to minimize these current loops and make the lines as short and wide as possible. And connect all GND lines at one point to reduce effects caused by above current noise to other lines ...
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... BD9853AFV ●Notes for use 1) Absolute maximum ratings Use of the IC in excess of absolute maximum ratings such as the applied voltage or operating temperature range may result in IC deterioration or damage. Assumptions should not be made regarding the state of the IC (short mode or open mode) when such damage is suffered. A physical safety measure such as a fuse should be implemented when use of the special mode where the absolute maximum ratings may be exceeded is anticipated ...
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... BD9853AFV 12) IC pin input This monolithic IC contains P+ isolation and PCB 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 to create a variety of parasitic elements. For example, when a resistor and transistor are connected to pins as shown in following chart, ...
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... BD9853AFV ●Ordering part number Part No. Part No. SSOP-B16 5.0±0 0.15±0.1 0.1 0.65 0.22±0.1 www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved Package FV: SSOP-B16 <Tape and Reel information> Tape Embossed carrier tape Quantity 2500pcs E2 Direction The direction is the 1pin of product is at the upper left when you hold ...
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