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www.rohm.com 2009.05 - Rev.A © 2009 ROHM Co., Ltd. All rights reserved. Large Current External FET Controller Type Switching Regulators Single-output Step-up,High-efficiency Switching Regulator (Controller Type) BD9763FVM

  • Description BD9763FVM is a 1-channel high efficiency step-up switching regulator. It is possible to choose small application space due to its high-speed operation (Max switching frequency 1.2MHz)
  • Features 1) Build-in under voltage lock out circuit. 2) High accuracy reference voltage (2.5V ±1.0%) 3) Establish maximum duty cycle internally. 4) CTL/SS terminal for both stand-by and soft-start functi on. (Soft-start time can be set by external capacitor) 5) MSOP8 thin and small package.
  • Applications Single-lens reflex cameras, digital video cameras, liquid crystal modules, DVD drive.
  • Absolute Maximum Ratings(Ta=25℃) Parameter Symbol Limit Unit Supply voltage Vcc 10 V Storage temperature range Tstg -55 to +150 ℃ Power dissipation Pd 587 * mW Junction temperature Tjmax +150 ℃ * IC mounted on a PCB board (70mm x 70mm x 1.6mm, glass epoxy). Reduced by 4.7mW for each increase in Ta of 1 ℃ over 25 ℃.
  • Recommended Operating Conditions Parameter Symbol Limit Unit Min Typ Max Supply voltage Vcc 4 7 9 V Oscillating frequency fosc 100 - 1200 kHz Operating temperature range Topr -40 - +85 ℃ No.09028EAT07

www.rohm.com 2009.05 - Rev.A © 2009 ROHM Co., Ltd. All rights reserved.

  • Electrical characteristics (Unless otherwise specified, Ta=25℃, Vcc=7.0V) Parameter Symbol Limits Unit Condition Min Typ Max 【Oscillator】 Oscillating frequency fosc 522 600 678 kHz R RT=24kΩ Frequency tolerance FDV -5 0 5 % Vcc=4 to 9V Swing voltage Vpptr - 0.5 - V 【Stand-by, Soft start】 CTL/SS pin source current ISS -1.90 -1.00 -0.55 µA V CTL/SS=1.5V CTL/SS pin clamp voltage VSS 2.2 2.4 2.6 V CTL threshold voltage VCTLTH 1.2 1.3 1.4 V 【PWM comparator】 0% threshold voltage D0 1.5 1.6 1.7 V Maximum duty cycle DMAX 80 90 99.5 % 【Error amplifier】 Threshold voltage VIN 0.98 1.00 1.02 V Band width BW - 3.0 - MHz AV=0dB Voltage gain Av - 70 - dB Input bias current IIB -150 -70 - nA Maximum output voltage VCH 2.3 2.4 2.6 V Minimum output current VCL - 0.03 0.20 V Output source current IOI -3.1 -1.6 -1.0 mA V FB=1.0V Output sink current IOO 12 50 125 mA V FB=1.0V 【Reference voltage】 Output voltage VREF 2.475 2.500 2.525 V I VREF=0mA Load regulation △VREFlo - - 10 mV I VREF=0 to -1mA Output short current IVREF -45 -16 -1 mA 【Whole device】 Stand-by current ICCS 420 610 960 µA Circuit current ICCA 3.4 5.0 7.8 mA No load 【Output】 ON resistance RON 0.9 2.5 8.0 Ω Output rise/fall time Tr/Tf - 20 - nsec Cout=1000pF Output source current IOUTSO - -0.80 - A Ta=-40 to 85℃,VCC=4 to 9V, OUT=0V,rush current Output sink current IOUTSI - 0.85 - A Ta=-40 to 85℃,VCC=4 to 9V, OUT=VCC,rush current 【Under voltage lock out】 Threshold voltage VUT 3.7 3.8 3.9 V Vcc sweep down Hysteresis width VUThy 0.05 0.10 0.15 V

www.rohm.com 2009.05 - Rev.A © 2009 ROHM Co., Ltd. All rights reserved. VREF voltage vs . Ambient temperature 2.47 2.48 2.49 2.5 2.51 2.52 2.53 -60 -40 -20 0 20 40 60 80 100 120 140 Ambient temperature [℃] VREF voltage [V] Oscillating frequency vs. Ambient temperature 550 560 570 580 590 600 610 620 630 640 650 -60 -40 -20 0 20 40 60 80 100 120 140 Ambient temperature [℃] Oscillating frequency [kHz] Oscillating frequency vs. Ambient temperature 1000 1020 1040 1060 1080 1100 1120 1140 1160 1180 1200 -60 -40 -20 0 20 40 60 80 100 120 140 Ambient temperature [℃] Oscillating frequency [kHz] Oscillating frequency vs. Timing resistance 100 1000 10000 1 10 100 1000 Timing resistance (RT) [kΩ] Oscillating frequency [kHz]

  • Reference data (Unless otherwise specified, Ta=25℃)
  • Block diagram Fig.5 Fig.1 VREF voltage – Ambient temperature Fig.2 Oscillating frequency – Timing resistance (R RT) Fig.3 Oscillating frequency – Ambient temperature Fig.4 Oscillating frequency – Ambient temperature RT=24kΩ RT=10kΩ (RT=24kΩ) (RT=10kΩ) 1.0V VREF VREF GND OUT VCC TRI RTVCC INV FB Error Amp Vdt PWM COMP U.V.L.O Vref T.S.D CTL/SS Clamper

www.rohm.com 2009.05 - Rev.A © 2009 ROHM Co., Ltd. All rights reserved. 8pin 7pin 6pin 5pin 1pin 2pin 3pin 4pin VCC OUT GND VREF RT CTL/SS FB INV

  • Pin configuration Fig.6
  • Pin number , Pin name Pin No. Pin name Function

1 VCC Power supply

2 OUT FET driver output

3 GND Ground

4 VREF Reference voltage (2.5V ±1%) output

5 INV Inverting input of error amplifier

6 FB Output of error amplifier

7 CTL/SS Stand-by switch/Soft start capacitor connecting pin

8 RT Timing resistor connecting pin

  • Block description ・VOLTAGE REFERENCE(VREF) BLOCK This voltage reference block generates 2.5V internal reference voltage. ・OSCILLATOR BLOCK Oscillator block sets the oscillating frequency adjusted by an external resistance in RT pin. The oscillating frequency can be set within a range of 100~1200kHz.. (See the description of how to set the frequency on page6.) ・PWM COMP The PWM comparator transforms the voltage outputted from error amp to PWM waveform and outputs to FET driver. The maximum duty cycle is limited up to 90%. ・ERROR AMP BLOCK The error amp block detects the output voltage from the INV pin, amplifies the difference between the detected voltage and the reference voltage, and outputs it to FB pin. The reference voltage is 1V±2%. ・PROTECTION CIRCUIT BLOCK The under voltage lock out circuit is activated to shut down the whole circuit when the VCC voltage is up to 3.8V. When the thermal shutdown circuit detects abnormal heating of the chip (150℃), the output becomes off. And the output turns back on when the chip temperature goes down to a specific level.

www.rohm.com 2009.05 - Rev.A © 2009 ROHM Co., Ltd. All rights reserved.

  • Application example Fig.7
  • Selecting application components (1) Output inductor It is recommended to use an inductor which satisfies the following rating current (the following value of current), and also has low DCR. The shield type inductor is preferable. I peak = Io・(Vo/VIN) / η + VIN ・(VOUT-VIN) / (2・VOUT・L・f) [A] [ Io : Output Vo : Output voltage VIN : Input voltage η : Efficiency L : Inductance f : Oscillating frequency ] (2) Output capacitor It is recommended to use the output capacitor which has the enough margin to maximum rating for output voltage and low fluctuation for temperature. The ripple voltage of the output is influenced by ESR of the output capacitor. Vripple = VIN・(VOUT-VIN) / (VOUT・L・f)・ESR [V] (f >> 1 / (2π√LC)・Vo / VIN) [ Io : Output Vo : Output voltage VIN : Input voltage η : Efficiency L : Inductance C : Output capacitor f : Oscillating frequency ] (3) FET It is recommended to use FETs which satisfy followings and have small Ciss or Qg and ON resistance. D-S Voltage : Over (Output voltage + Vf of Di) G-S Voltage : Over input voltage D-S Current : Over Ipeak at the section of output inductor (4) Diode It is recommended to use a schottky diode which satisfies followings and has low forward voltage drop and high switching speed. Maximum current : Over maximum output current Direct reverse voltage : Over output voltage * Please provide sufficient margin in the choice of external components by factoring into the worst case characteristics and temperature range. VOUT VCC VCC OUT GND VREF RT CTL/SS FB INV ON/OFF H:OFF L:ON *1μF *RRT R1 R2

www.rohm.com 2009.05 - Rev.A © 2009 ROHM Co., Ltd. All rights reserved. Oscillating frequency vs. Timing resistance 100 1000 10000 1 10 100 1000 Timing resistance (RT) [kΩ] Oscillating frequency [kHz] (5) Setting the oscillator frequency Refer to Fig.5 and determine Timing resistor (RRT) when setting the oscillating frequency. Fig.8 Oscillating frequency – Timing resistance (R RT) (6) Setting the output voltage The output voltage is calculated by the following equation. Vo = VINVth・(R1+R2)/R2 [V] R1,R2 : Resistor divider network VINth : Error amp threshold voltage (typ.1V) ( b u t V o < V I N・5 because of MAXDUTY Min=80%) (7) CTL/SS setting the soft start time The time after CTL/SS is released before the output voltage starts to rise. t(start) = CCTL・(VDo-Voff)/Iss [S] approximated equation The time after the output voltage starts up before it reaches the specified output level. t(soft) = CCTL・(VDUTY-VDo)/Iss [S] approximated equation VDUTY = VDo+0.5・(1-VIN/VOUT) [V] CCTL : CTL/SS–GND capacitande Vdo : 0% duty threshol d (Typ 1.6V) Voff : Output off CTL/SS voltage Iss : CTL/SS charge current (Typ 1uA) VDUTY : stabilization operating ON duty.

  • Timing chart Fig.9 Output waveform ON/OFF Oscillator output Stand-by threshold voltage t(start) t(soft) VDUTY Dead-time setting voltage CTL/SS terminal voltage FB terminal voltage

www.rohm.com 2009.05 - Rev.A © 2009 ROHM Co., Ltd. All rights reserved.

  • Recommended board patterns *Place these parts with attention about patterns shown in following Fig.7 Fig.10 C1 : Capacitor terminals have to be close enough to terminals of VCC and GND. It is safe to pass OUT signal line under C1. C2 : Capacitor terminals have to be close enough to terminals of VREF and GND. R1 : Pattern area has to be small enough to reduce parasitic capacitance of RT terminal. Fig.11 Recommended board patterns VCC OUT GND VREF RT CTL/SS FB INV RT RRT VCC OUT GND VREF L:ON VOUT VCC VCC OUT GND VREF RT CTL/SS FB INV H:OFF 1μF * RRT R1 R2 FET L Di Lay out by the shortest pattern. Short GNDs at one point as this figure.

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  • I/O Equivalent Circuit OUT (2) VREF (4) INV (5) FB (6) CTL/SS (7) RT (8) Fig.12 VCC OUT GND 250k GND 1.67k VCC VREF 200k 50k 193k ~ ~ VCC INV GND VREF RT GND 500k 1k 100k GND FB 20p 200k VCC CTL/SS GND 20k 5k VCC

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  • Operation Notes (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 fuse should be implemented when use of the IC in a special mode where the absolute maximum ratings may be exceeded is anticipated. (2) GND potential Ensure a minimum GND pin potential in all operating conditions. In addition, ensure that no pins other than the GND pin. Carry a voltage lower then or equal to the GND pin, including during actual transient phenomena. (3) Thermal design Use a thermal design that allows for a sufficient margin in light of the power dissipation (Pd) in actual operating conditions. (4) Inter-pin shorts and mounting errors Use caution when orienting and positioning the IC for mounting on printed circuit boards. Improper mounting may result in damage to the IC. Shorts between output pins or between output pins and the power supply and GND pin caused by the presence of a foreign object may result in damage to the IC. (5) Operation in a strong electromagnetic field Use caution when using the IC in the presence of a strong electromagnetic field as doing so may cause the IC to malfunction. (6) Thermal shutdown circuit (TSD circuit) This IC incorporates a built-in thermal shutdown circuit (TSD circuit). The TSD circuit designed only to shut the IC off to prevent runaway thermal operation. do not continue to use the IC after operating this circuit or use the IC in an environment where the operation of the thermal shutdown circuit is assumed. (7) Testing on application boards When testing the IC on an application board, connecting a capacitor to pin with low impedance subjects the IC to stress. Always discharge capacitors after each process or step. Ground the IC during assembly steps as an antistatic measure, and use similar caution when transporting or storing the IC. Always turn the IC’s power supply off before connecting it to or removing it from a jig or fixture the inspection process. (8) Common impedance Power supply and ground wiring should reflect consideration of the need to lower common impedance and minimize ripple as much as possible (by making wiring as short and thick as possible or rejecting ripple by incorporating inductance and capacitance). (9) Applications with modes that reverse VCC and pin potentials may cause damage to internal IC circuits. For example, such damage might occur when VCC is shorted with the GND pin while an external capacitor is charged. It is recommended to insert a diode for preventing back current flow in series with VCC or bypass diodes between VCC and each pin. Fig.13 (10) Timing resistor Timing resistor connected between RT and GND, has to be placed near RT terminal (8pin). And pattern has to be short Enough. Output pin VCC Back current prevention diode Bypass diode

www.rohm.com 2009.05 - Rev.A © 2009 ROHM Co., Ltd. All rights reserved. (11) 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 Fig.14, ○the P/N junction functions as a parasitic diode when GND > (Pin A) for the resistor or GND > (Pin B) for the transistor (NPN). ○Similarly, when GND > (Pin B) for the transistor (NPN), the parasitic diode described above combines With the N layer of other adjacent elements to operate as a parasitic NPN transistor. The formation of parasitic elements as a result of the relationships of the potentials of different pins is an inevitable result of the IC’s architecture. The operation of parasitic elements can cause interference with circuit operation as well as IC malfunction and damage. For these reasons, it is necessary to use caution so that the IC is not used in away that will trigger the operation of parasitic elements, such as by the application of voltage lower than the GND (PCB) voltage to input and output pins. Fig.14

  • Power Dissipation Reduction Fig.15 0.4 0.6 0.2 50 15075 100 1250 25 AMBIENT TEMPERATURE : Ta(℃) pd(W) 0.8 175 IC mounted on a ROHM standard board (70mm x 70mm x 1.6mm, glass epoxy) POWER DISSIPATION : pd(W) B C E Parasitic diode PCB N GND PP P N B EC P P N N P NNN (Pin A) (Pin B) PCB GND Parasitic transistors GND Parasitic diode (Pin A) GND (Pin B) GND Parasitic elements Other adjacent element 0.587W

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  • Ordering part number B D 9 7 6 3 F V M - T R Part No. Part No. Package FVM: MSOP8 Packaging and forming specification TR: Embossed tape and reel ( M S O P 8 ) (Unit : mm) MSOP8 0.08 S S 4.0±0.2 2.8±0.1 2.9±0.1 0.475 5 7 (MAX 3.25 include BURR) 1PIN MARK 0.9MAX 0.75±0.05 0.65 0.08±0.05 0.22 +0.05–0.04 0.6±0.2 0.29±0.15 0.145 +0.05 –0.03 4°+6° −4° Direction of feed Reel ∗ Order quantity needs to be multiple of the minimum quantity. <Tape and Reel information> Embossed carrier tapeTape Quantity Direction of feed The direction is the 1pin of product is at the upper right when you hold reel on the left hand and you pull out the tape on the right hand 3000pcs TR 1pin

R0039Awww.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. Notice ROHM Customer Support System http://www.rohm.com/contact/ Thank you for your accessing to ROHM product informations. More detail product informations and catalogs are available, please contact us. Notes N o c o p y i n g o r r e p r o d u c t i o n o f t h i s d o c u m e n t , i n p a rt o r i n w h o l e , i s p e r m i t t e d w i t h o u t t h e consent of ROHM Co.,Ltd. The content specified herein is subject to change for improvement without notice. The content specified herein is for the purpose of introducing ROHM's products (hereinafter "Products"). If you wish to use any such Product, please be sure to refer to the specifications, which can be obtained from ROHM upon request. Examples of application circuits, circuit constants and any other information contained herein illustrate the standard usage and operations of the Products. The peripheral conditions must be taken into account when designing circuits for mass production. Great care was taken in ensuring the accuracy of the information specified in this document. However, should you incur any damage arising from any inaccuracy or misprint of such information, ROHM shall bear no responsibility for such damage. The technical information specified herein is intended only to show the typical functions of and examples of application circuits for the Products. ROHM does not grant you, explicitly or implicitly, any license to use or exercise intellectual property or other rights held by ROHM and other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the use of such technical information. The Products specified in this document are intended to be used with general-use electronic equipment or devices (such as audio visual equipment, office-automation equipment, commu- nication devices, electronic appliances and amusement devices). The Products specified in this document are not designed to be radiation tolerant. While ROHM always makes efforts to enhance the quality and reliability of its Products, a Product may fail or malfunction for a variety of reasons. Please be sure to implement in your equipment using the Products safety measures to guard against the possibility of physical injury, fire or any other damage caused in the event of the failure of any Product, such as derating, redundancy, fire control and fail-safe designs. ROHM shall bear no responsibility whatsoever for your use of any Product outside of the prescribed scope or not in accordance with the instruction manual. T h e P r o d u c t s a r e n o t d e s i g n e d o r m a n u f a c t u r e d t o b e u s e d w i t h a n y e q u i p m e n t , d e v i c e o r system which requires an extremely high level of reliability the failure or malfunction of which may result in a direct threat to human life or create a risk of human injury (such as a medical instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, fuel-controller or other safety device). ROHM shall bear no responsibility in any way for use of any of the Products for the above special purposes. If a Product is intended to be used for any such special purpose, please contact a ROHM sales representative before purchasing. If you intend to export or ship overseas any Product or technology specified herein that may be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to obtain a license or permit under the Law.