BD9C401EFJ-E2

Datasheet 4.5V to 18V Input, 4.0A Integrated MOSFET Single Synchronous Buck DC/DC Converter BD9C401EFJ General Description BD9C401EFJ is a synchronous buck switching regulator with built-in low on-resistance power MOSFETs. With wide input voltage range, It is capable of providing current of up to 4A. It is a current mode control DC/DC converter a n d f e a t u r e s h i g h - s p e e d t r a n s i e n t r e s p o n s e. Phase compensation can also be set easily. Features ■ Synchronous Single DC/DC Converter ■ Over Current Protection ■ Thermal Shutdown Protection ■ Under Voltage Lockout Protection ■ Short Circuit Protection ■ Fixed Soft Start Function Key Specifications  Input Voltage Range:  Reference Voltage:  Maximum Output Current:  Switching Frequency:  Pch MOSFET On Resistance:  Nch MOSFET On Resistance:  Standby Current:  Operating Temperature Range: Package HTSOP-J8 4.5V to 18.0V 0.8V ± 1% 4A(Max) 500kHz(Typ) 65mΩ(Typ) 35mΩ(Typ) 1μA (Typ) -40°C to +85°C W(Typ) x D(Typ) x H(Max) 4.90mm x 6.00mm x 1.00mm Applications ■ LCD TVs ■ Set-top Boxes ■ DVD/Blu-ray Disc Players/Recorders ■ Broadband Network and Communication Interface ■ Entertainment Devices HTSOP-J8 Typical Application Circuit VIN 12V VIN 10µF 4.7µH 0.1µF VOUT 3.3V SW Enable EN COMP AGND 22µF×2 PGND FB Figure 1. Application Circuit 〇Product structure: silicon monolithic integrated circuit 〇This product has no protection against radioactive rays www.rohm.com TSZ02201-0J2J0AJ00440-1-2 © 2013 ROHM Co., Ltd. All rights reserved. 1/20 TSZ22111 • 14 • 001 24.JUL.2018 Rev.004 BD9C401EFJ Pin Configuration (TOP VIEW) PGND 1 8 SW VIN 2 7 SW AGND 3 6 EN FB 4 5 COMP Figure 2. Pin Assignment Pin Descriptions Pin No. Pin Name Function 1 PGND 2 VIN 3 AGND 4 FB 5 COMP 6 EN Turning this pin signal low (0.8 V or lower) forces the device to enter the shutdown mode. Turning this pin signal high (2.0 V or higher) enables the device. This pin must be terminated. SW Switch nodes. These pins are connected to the drain of Pch MOSFET and the drain of Nch MOSFET. E-Pad A backside heat dissipation pad. Connecting to the internal PCB ground plane by using multiple vias provides excellent heat dissipation characteristics. Ground pins for the output stage of the switching regulator. This pins supply power to the control circuit and the output stage of the switching regulator. Connecting a 10 µF and a 0.1µF ceramic capacitor is recommended. Ground pin for the control circuit. An inverting input node for the gm error amplifier. See page 14 for how to calculate the resistance of the output voltage setting. An input pin for the switch current comparator and an output pin for the gm error amplifier. Connect a frequency phase compensation component to this pin. See page 14 for how to calculate the resistance and capacitance for phase compensation. 7 8 - www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 2/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Block Diagram EN 6 VREF OSC SCP OCP UVLO IBIAS VIN TSD 2 S FB 7 SW 8 LOGIC ERR 4 OUTPUT SLOPE COMP PWM 5 R PGND 1 SoftStart 3 AGND Figure 3. Block Diagram Absolute Maximum Ratings (Ta = 25C) Parameter Symbol Rating Unit Supply Voltage VIN 20 V SW Pin Voltage VSW 20 V EN Pin Voltage VEN 20 V Power Dissipation (Note 1) Pd 3.76 W Operating Temperature Range Topr -40 to +85 °C Storage Temperature Range Tstg -55 to +150 °C Tjmax 150 °C VLVPINS 7 V Maximum Junction Temperature FB, COMP Pin Voltage Conditions When mounted on a 70 mm x 70 mm x 1.6 mm 4-layer glass epoxy board (Note1) Derate by 30.08 mW when operating above 25C. Caution: Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit between pins or an open circuit between pins and the internal circuitry. Therefore, it is important to consider circuit protection measures, such as adding a fuse, in case the IC is operated over the absolute maximum ratings. Recommended Operating Range (Ta= -40°C to +85°C) Parameter Symbol Rating Min Typ Max Unit Supply Voltage VIN 4.5 - 18.0 V Output Current IOUT - - 4.0 A VRANGE VIN × 0.125(Note 1) - VIN × 0.7 V Output Voltage Setting Range (Note 1) VIN x 0.125 ≥ 0.8 [V] www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 3/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Electrical Characteristics (Ta = 25C, VIN = 12 V, VEN = 5 V unless otherwise specified) Parameter Symbol Limits Min Typ Max Unit Conditions Circuit Current in Active IQ_active - 1.5 2.5 mA VFB= 0.75V, VEN= 5V Circuit Current in Standby IQ_stby - 1.0 10.0 μA VEN = 0V FB Pin Voltage VFB 0.792 0.800 0.808 V FB-COMP Short (Voltage follower) FB Input Current IFB - 0 2 μA Switching Frequency fOSC 450 500 550 kHz High Side FET On Resistance RONH - 65 - mΩ VIN= 12V , ISW = -1A Low Side FET On Resistance RONL - 35 - mΩ VIN= 12V , ISW = -1A Power MOS Leakage Current ILSW - 0 5 μA VIN= 18V , VSW = 18V Current Limit ILIMIT 4.5 - - A Min_duty - - 12.5 % VUVLO 3.75 4.0 4.25 V VUVLOHYS - 0.2 - V EN High-Level Input Voltage VENH 2.0 - - V EN Low-Level Input Voltage VENL - - 0.8 V Soft Start Time TSS 0.5 1.0 2.0 msec Minimum Duty Ratio UVLO Threshold UVLO Hysteresis Voltage (Note 1) VFB :FB Pin Voltage, VEN :EN Pin Voltage, (Note 2) Current capability should not exceed Pd. www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 VIN Sweep up ISW :SW Pin Current 4/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Typical Performance Curves 100 60 90 80 VOUT = 5.0V 50 VOUT = 3.3V 60 Tc[℃] Efficiency [%] 70 50 40 40 30 30 20 10 20 0 0 0.5 1 1.5 2 2.5 3 0 1 2 ILOAD[A] Vout(AC) SW 3 ILOAD[A] Figure 4. Efficiency Figure 5. TC vs ILOAD (VIN=12V, L=4.7µH) (VIN=12V, Vout=3.3V, L=4.7µH, Cout=44µF) [20mV/div] Vout(AC) [5V/div] SW T - Time - 1µsec/div [20mV/div] [5V/div] T - Time - 1µsec/div Figure 6. Vout Ripple Figure 7. Vout Ripple (VIN=12V, Vout=3.3V, L=4.7µH, Cout=44µF, Iout=0A) (VIN=12V, Vout=3.3V, L=4.7µH, Cout=44µF, Iout=4A) www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 4 5/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ 3.40 3.40 3.38 3.38 3.36 3.36 3.34 3.34 3.32 3.32 Vout [V] Vout [V] Typical Performance Curves (Continued) 3.30 3.28 3.30 3.28 3.26 3.26 3.24 3.24 3.22 3.22 3.20 3.20 0 1 2 3 4 4 6 8 10 12 14 16 ILOAD [A] Figure 8. Load Regulation VIN [V] Figure 9. Line Regulation (VIN=12V, Vout=3.3V, L=4.7µH, Cout=44µF) (Vout=3.3V, L=4.7µH, Cout=44µF, Iout=0A) 560 18 3.40 3.38 3.36 3.34 520 3.32 Vout [V] Frequency [kHz] 540 500 480 3.30 3.28 3.26 3.24 460 3.22 440 3.20 4 6 8 10 12 14 16 18 -40 -20 0 20 40 60 80 VIN [V] Figure 10. Switching Frequency Ta [℃] Figure 11. Vout vs Temperature (Vout=3.3V, L=4.7µH, Cout=44µF, Iout=0A) (Vin=12V, Vout=3.3V, L=4.7µH, Cout=44µF, Iout=0A) www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 6/20 100 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Typical Performance Curves (Continued) EN [5V/div] EN [5V/div] Vout [2V/div] Vout [2V/div] SW SW [10V/div] T - Time – 1msec/div [10V/div] T - Time – 200msec/div Figure 12. Start-up with EN Figure 13. Shutdown Wave Form (Vin=12V, Vout=3.3V, L=4.7µH, Cout=44µF, Iout=0A) (Vin=12V, Vout=3.3V, L=4.7µH, Cout=44µF, Iout=0A) Vout [5V/div] Δ = +105mV Δ = -100mV SW VOUT (AC) [100mV/div] [20V/div] IL [5A/div] Iout [1A/div] T - Time – 1msec/div T - Time - 200µsec/div Figure 14. Transient Response Figure 15. OCP Function (Vin=12V, Vout=3.3V, L=4.7µH, Cout=44µF, Iout=2A) (Vin=12V, Vout=3.3V, L=4.7µH, Cout=44µF, Vout is short to GND) www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 7/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Function Explanations 1. Enable control The IC shutdown can be controlled by the voltage applied to the EN pin. When VEN reaches 2.0 V, the internal circuit is activated and the IC starts up. VIN 0V EN VENH VENL 0V Vout 0V TSS Figure 16. Timing Chart of Enable Control 2. Protective Functions The protective circuits are intended for prevention of damage caused by unexpected accidents. Do not use them for continuous protective operation. 2-1. Short Circuit Protection Function (SCP) The short circuit protection block (SCP) compares the FB pin voltage with the internal reference voltage VREF. When the FB pin voltage fall below VSCP (= VREF – 240mV) and with that situation continuing for off latch time, it latches output in off situation. Table 1. Short Circuit Protection Function EN Pin Short Circuit Protection Function FB Pin < VSCP 2.0 V or higher 0.8 V or lower ON Enabled > VSCP - Short Circuit Protection Operation OFF Disabled OFF Soft start Typ：1msec VOUT1 SCP delay time Typ：1msec SCP delay time Typ：1msec 0.8V FB SCP threshold：0.56Ｖ SCP release before counter fix HG SCP Protect HG=H LG=L LG OCP threshold IL EN EN threshold Normal operation OCP Normal operation OCP SCP (OFF Latch) Stand by Normal operation latch release by EN or UVLO HG Hi side FET GATE signal LG : Low side FET GATE signal Figure 17. Short Circuit Protection function (SCP) timing chart www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 8/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ 2-2. Under Voltage Lockout Protection (UVLO) The Under Voltage Lockout Protection (UVLO) circuit monitors the VIN pin voltage. The device stops the switching operation and the output voltage drops when the VIN pin voltage is 3.8V (Typ) in the case of VIN sweep down. The device starts the switching operation and the output voltage gradually rises when the VIN pin voltage is 4.0V (Typ) in the case of VIN sweep up. In the case of the application that EN pin is shortened to VIN pin like Figure 18-a, please use the UVLO function on the below conditions. · VIN Sweep Down: Set the falling slew rate of VIN to 0.9V/ms or more and drop the VIN voltage to 0V. · VIN Sweep Up: Set the rising slew rate of VIN to 1.8V/ms or more and start the VIN voltage from 0V. If the slew rate is slower than the above values, UVLO circuit is not able to operate normally and the output of UVLO block may become indefinite at the lower VIN voltage than UVLO release or detect voltage. The Vout voltage may be re-outputted in the case of the indefinite UVLO output. If the VIN pin voltage has the rising slew rate of less than 1.8V/ms or the falling slew rate of less than 0.9V/ms, the start-up and shutdown must be controlled by EN function instead of UVLO function as shown Figure 18-b. VIN (=EN) Vout UVLO Detect Voltage Hysteresis UVLO Release Voltage 0V 0.9V/ms or more 1.8V/ms or more Vout 0V TSS Figure 18-a. UVLO Timing Chart (VIN=EN) VIN UVLO Detect Voltage UVLO Release Voltage 0V Less than 1.8V/ms Less than 0.9V/ms EN VENH VENL 0V Vout 0V TSS Figure 18-b. EN Control Timing Chart in the case of slow VIN slew rate If there is any questions about above EN control or considerations of other control method, please contact us. www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 9/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ 2-3. Thermal Shutdown When the chip temperature exceeds Tj = 175°C (Typ), the DC/DC converter output is stopped. The thermal shutdown circuit is intended for shutting down the IC from thermal runaway in an abnormal state with the temperature exceeding Tjmax = 150C (Typ). It is not meant to protect or guarantee the soundness of the application. Do not use the function of this circuit for application protection design. VIN EN SCP delay time Typ:1msec Vout SCP threshold Soft Start Tj TSD release HG LG Normal operation TSD Normal operation TSD TSD release SCP (OFF Latch) Normal operation HG : Hi side FET GATE signal LG : Low side FET GATE signal Figure 19. TSD Timing chart 2-4. Over Current Protection The Over Current Protection operates by using the current mode control to limit the current that flows through the top MOSFET at each cycle of the switching frequency. When an abnormal state continues, the output is fixed in a low level. 2-5. Error detection (off latch) release method BD9C401EFJ enters the state of off latch when the protection function operates. To release the off latch state, the VIN pin voltage should be changed to less than UVLO level (=3.8V [Typ] ) or, the EN pin voltage falls below VENL.voltage. www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 10/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Application Example PGND SW 1 VIN (12V) Cin1 10µF 8 Cin2 0.1µF L 4.7µH VOUT (3.3V) SW VIN Cout 22µF×2 7 2 AGND BD9C401EFJ EN 6 3 R_DW 2.4kΩ COMP FB 5 Rcmp 12kΩ 4 Ccmp 4700pF R_UP 7.5kΩ Figure 20. Application Circuit (VIN=12V, VOUT=3.3V) *Please confirm the above components values and the characteristics on the application board because there is a case needed to adjust the values due to the application load. *If it is considered to use the other application circuit or the other components values, please contact us. Input capacitor(Cin1) Input capacitor(Cin2) Output capacitor(Cout) Inductor (L) Maker TDK TDK TDK TDK 10µF/25V 0.1µF/25V 22µF/16V x 2 4.7µH Part No C3225JB1E106K C1608JB1H104K C3216JB1C226M x 2 SPM6530-4R7 The example of output voltage setting at VIN=12V FB Vo(V) R_UP [kΩ] R_DW [kΩ] 5 4.3 0.82 3.3 7.5 2.4 1.8 15 12 1.5 16 18 1.2(Note1) 10 20 1(Note1) 5.1 20 (Note 1) VOUT has restriction with VIN. See page 14. www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 11/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ PCB Layout Design In the step-down DC/DC converter, a large pulse current flows into two loops. The first loop is the one into which the current flows when the top FET is turned ON. The flow starts from the input capacitor C IN, runs through the FET, inductor L and output capacitor COUT and back to GND of CIN via GND of COUT. The second loop is the one into which the current flows when the bottom FET is turned on. The flow starts from the bottom FET, runs through the inductor L and output capacitor COUT and back to GND of the bottom FET via GND of COUT. Route these two loops as thick and as short as possible to allow noise to be reduced for improved efficiency. It is recommended to connect the input and output capacitors directly to the GND plane. The PCB layout has a great influence on the DC/DC converter in terms of all of the heat generation, noise and efficiency characteristics. VIN MOS FET CIN VOUT L COUT GND Figure 21. Current Loop of Buck Converter Accordingly, design the PCB layout considering the following points.      Connect an input capacitor as close as possible to the IC VIN pin on the same plane as the IC. If there is any unused area on the PCB, provide a copper foil plane for the GND node to assist heat dissipation from the IC and the surrounding components. Switching nodes such as SW are susceptible to noise due to AC coupling with other nodes. Route the coil pattern as thick and as short as possible. Provide lines connected to FB and COMP far from the SW nodes. Place the output capacitor away from the input capacitor in order to avoid the effect of harmonic noise from the input. Vout SW L IC GND VIN Top layer Mid layer1 Mid layer2 Bottom layer Figure 22. Example of evaluation board layout www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 12/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Selection of Components Externally Connected 1. Output LC Filter Constant The DC/DC converter requires an LC filter for smoothing the output voltage in order to supply a continuous current to the load. Selecting an inductor with a large inductance causes the ripple current ∆I L that flows into the inductor to be small. However, decreasing the ripple voltage generated in the output is not advantageous in terms of the load transient response characteristic. An inductor with a small inductance improves the transient response characteristic but causes the inductor ripple current to be large which increases the ripple voltage in the output voltage, showing a trade-off relationship. It is recommended to select an inductance such that the size of the ripple current component of the coil will be 20% to 40% of the average output current (average inductor current). VIN IL Inductor saturation current > IOUTMAX +ΔIL /2 ΔIL IOUTMAX L Driver Average inductor current VOUT COUT t Figure 23. Waveform of current through inductor Figure 24. Output LC filter circuit With VIN = 12 V, VOUT = 3.3 V and the switching frequency FOSC = 500 kHz, the calculation is shown in the following equation. Coil ripple current ΔIL = 30% x Average output current (4A) = 1.2 [A] L = V OUT × (V 　 IN -V OUT ) × 1 = 3.99μ ≒4.7μ V IN × FOSC × ⊿I L [H] where : FOSC is a switching f requency The saturation current of the inductor must be larger than the sum of the maximum output current and 1/2 of the inductor ripple current ∆IL. The output capacitor COUT affects the output ripple voltage characteristics. The output capacitor COUT must satisfy the required ripple voltage characteristics. The output ripple voltage can be represented by the following equation. ⊿V RPL = ⊿I L × (R 　 ESR + 1 ) 　 [V] 8 × C OUT × FOSC where : R ESR is the Equiv alent Series Resistance (ESR) of the output capacitor. Also this IC provides 1msec[Typ] soft start function to reduce sudden current which flows in output capacitor when startup. But when capacity value of output capacitor COUT becomes bigger than the following method, correct soft start waveform may not appear in some cases. ( ex. Vout over shoot at soft start .) Select output capacitor COUT fulfilling the following condition including scattering and margin.. C OUT < I OCP (= 4.5A[min])× TSS (= 0.5ms[min]) VOUT 　 [F] where : I OCP 　 is switch current restrictedv alue TSS 　 is sof tstart time Caution) Concerning COUT total the capacity value of every part connected to Output line. www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 13/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ 2. Output Voltage Setting The output voltage value can be set by the feedback resistance ratio. 𝑉𝑂𝑈𝑇 = VOUT VFB ERR 𝑅1 +𝑅2 𝑅2 × 𝑉𝐹𝐵 [V] VFB is 0.8V (Typ) at VIN=12V. The output voltage can be calculated as below formula. R1 𝑉𝑂𝑈𝑇 = FB R2 𝑅1 +𝑅2 𝑅2 × 0.800 [V] Output voltage VOUT and VFB have the VIN dependence as shown in Figure 9 VOUT Line Regulation. For example, the output voltage at VIN=5V can be set as below. Figure 25. Feedback Resistors Circuit 𝑉𝑂𝑈𝑇 = 𝑅1 +𝑅2 𝑅2 × 0.793 [V] If it is considered to use on the other input voltage, please refer to Figure 9 and set the output voltage value by considering the VIN dependence. Please contact us if needed. VOUT has restriction with VIN by the following equation. VOUTMIN: VIN x 0.125 (VIN x 0.125 ≥ 0.8V) VOUTMAX: VIN x 0.7 3. Phase Compensation Component A current mode control buck DC/DC converter is a two-pole, one-zero system. Two poles are formed by an error amplifier and load and the one zero point is added by phase compensation. The phase compensation resistor RCMP determines the crossover frequency FCRS where the total loop gain of the DC/DC converter is 0 dB. A high value crossover frequency FCRS provides a good load transient response characteristic but inferior stability. Conversely, a low value crossover frequency FCRS greatly stabilizes the characteristics but the load transient response characteristic is impaired. Here, select the constant so that the crossover frequency FCRS will be 1/20 of the switching frequency. (1) Selection of Phase Compensation Resistor RCMP The Phase Compensation Resistance RCMP can be determined by using the following equation. RCMP = 2π × VOUT × FCRS × COUT 　 V FB × G MP × G MA [Ω] (3-1) VOUT is Output Voltage FCRS is Crossov erFrequency C OUT is Output Capacitance V FB is Feedback Ref erenceVoltage (0.8 V (Ty p)) G MP is Current Sense Gain (7.8 A/V (Ty p)) G MA is Error Amplif ierTrans conductance (300 μA/V (Ty p)) (2) Selection of Phase Compensation Capacitance CCMP The phase compensation capacitance CCMP can be determined by using the following equation. CCMP = VOUT × COUT 　 [F] (3-2) IOUT × RCMP *When capacity value of CCMP and resistance value of RCMP don’t meet the following method, correct soft start waveform may not appear in some cases. Select CCMP and RCMP fulfilling the following condition including scattering and margin so that VCMP voltage reaches 1.4V or over within Off-latch delay time of SCP detection (500µsec(MIN) ). VCMP  RCMP × ICMP + ICMP × T  1.4 CCMP www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 [V] 14/20 (3-3) TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ ICMP × T  0.715 CCMP [V] (3-4) VCMP is COMP Terminal voltage RCMP is resistor connected to COMP Terminal CCMP is capacitor connected to COMP Terminal ICMP is Error Amplifier Source Current (45uA(MIN)) T is SCP delay time(500µsec(MIN) ) (3) Loop Stability To ensure the stability of the DC/DC converter, make sure that a sufficient phase margin is provided. A phase margin of at least 45º in the worst conditions is recommended. VOUT RUP (a) A Gain [dB] FB COMP GBW(b) 【dB】 RDW 0.8V RCMP CCMP 0 Phase[deg] －90° －90 PHASE MARGIN Phase 【°】 f FCRS 0 －180° －180 f Figure 26. Phase Compensation Circuit Figure 27. Bode Plot I/O Equivalent Circuit Diagram 4.FB 5. COMP VIN VREG 20kΩ FB 10kΩ VIN 2kΩ 0.5kΩ 2kΩ COMP 0.5kΩ 10kΩ AGND AGND 6.EN 7,8.SW ＶＩＮ VIN EN 250kΩ ＳＷ 725kΩ AGND ＰＧＮＤ Figure 28. www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 15/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Operational Notes 1. Reverse Connection of Power Supply Connecting the power supply in reverse polarity can damage the IC. Take precautions against reverse polarity when connecting the power supply, such as mounting an external diode between the power supply and the IC’s power supply pins. 2. Power Supply Lines Design the PCB layout pattern to provide low impedance supply lines. Separate the ground and supply lines of the digital and analog blocks to prevent noise in the ground and supply lines of the digital block from affecting the analog block. Furthermore, connect a capacitor to ground at all power supply pins. Consider the effect of temperature and aging on the capacitance value when using electrolytic capacitors. 3. Ground Voltage Ensure that no pins are at a voltage below that of the ground pin at any time, even during transient condition. 4. Ground Wiring Pattern When using both small-signal and large-current ground traces, the two ground traces should be routed separately but connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal ground caused by large currents. Also ensure that the ground traces of external components do not cause variations on the ground voltage. The ground lines must be as short and thick as possible to reduce line impedance. 5. Thermal Consideration Should by any chance the power dissipation rating be exceeded the rise in temperature of the chip may result in deterioration of the properties of the chip. The absolute maximum rating of the Pd stated in this specification is when the IC is mounted on a 70mm x 70mm x 1.6mm 4-layer glass epoxy board. In case of exceeding this absolute maximum rating, increase the board size and copper area to prevent exceeding the Pd rating. 6. Recommended Operating Conditions These conditions represent a range within which the expected characteristics of the IC can be approximately obtained. The electrical characteristics are guaranteed under the conditions of each parameter. 7. Inrush Current When power is first supplied to the IC, it is possible that the internal logic may be unstable and inrush current may flow instantaneously due to the internal powering sequence and delays, especially if the IC has more than one power supply. Therefore, give special consideration to power coupling capacitance, power wiring, width of ground wiring, and routing of connections. 8. Operation Under Strong Electromagnetic Field Operating the IC in the presence of a strong electromagnetic field may cause the IC to malfunction. 9. Testing on Application Boards When testing the IC on an application board, connecting a capacitor directly to a low-impedance output pin may subject the IC to stress. Always discharge capacitors completely after each process or step. The IC’s power supply should always be turned off completely before connecting or removing it from the test setup during the inspection process. To prevent damage from static discharge, ground the IC during assembly and use similar precautions during transport and storage. 10. Inter-pin Short and Mounting Errors Ensure that the direction and position are correct when mounting the IC on the PCB. Incorrect mounting may result in damaging the IC. Avoid nearby pins being shorted to each other especially to ground, power supply and output pin. Inter-pin shorts could be due to many reasons such as metal particles, water droplets (in very humid environment) and unintentional solder bridge deposited in between pins during assembly to name a few. www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 16/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Operational Notes – continued 11. Unused Input Pins Input pins of an IC are often connected to the gate of a MOS transistor. The gate has extremely high impedance and extremely low capacitance. If left unconnected, the electric field from the outside can easily charge it. The small charge acquired in this way is enough to produce a significant effect on the conduction through the transistor and cause unexpected operation of the IC. So unless otherwise specified, unused input pins should be connected to the power supply or ground line. 12. Regarding the 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 the P layers with the N layers of other elements, creating a parasitic diode or transistor. For example (refer to figure below): When GND > Pin A and GND > Pin B, the P-N junction operates as a parasitic diode. When GND > Pin B, the P-N junction operates as a parasitic transistor. Parasitic diodes inevitably occur in the structure of the IC. The operation of parasitic diodes can result in mutual interference among circuits, operational faults, or physical damage. Therefore, conditions that cause these diodes to operate, such as applying a voltage lower than the GND voltage to an input pin (and thus to the P substrate) should be avoided. Resistor Transistor (NPN) Pin A Pin B C E Pin A N P+ P N N P+ N Pin B B Parasitic Elements N P+ N P N P+ B N C E Parasitic Elements P Substrate P Substrate GND GND Parasitic Elements GND Parasitic Elements GND N Region close-by Figure 29. Example of monolithic IC structure 13. Ceramic Capacitor When using a ceramic capacitor, determine the dielectric constant considering the change of capacitance with temperature and the decrease in nominal capacitance due to DC bias and others. 14. Area of Safe Operation (ASO) Operate the IC such that the output voltage, output current, and power dissipation are all within the Area of Safe Operation (ASO). 15. Thermal Shutdown Circuit(TSD) This IC has a built-in thermal shutdown circuit that prevents heat damage to the IC. Normal operation should always be within the IC’s power dissipation rating. If however the rating is exceeded for a continued period, the junction temperature (Tj) will rise which will activate the TSD circuit that will turn OFF all output pins. When the Tj falls below the TSD threshold, the circuits are automatically restored to normal operation. Note that the TSD circuit operates in a situation that exceeds the absolute maximum ratings and therefore, under no circumstances, should the TSD circuit be used in a set design or for any purpose other than protecting the IC from heat damage. 16. Over Current Protection Circuit (OCP) This IC incorporates an integrated overcurrent protection circuit that is activated when the load is shorted. This protection circuit is effective in preventing damage due to sudden and unexpected incidents. However, the IC should not be used in applications characterized by continuous operation or transitioning of the protection circuit. www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 17/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Power Dissipation HTSOP-J8 Package Board size: 70mm x 70mm x 1.6mm (1) 4-layer board (surface heat dissipation copper foil 70mm  70mm) (2) 2-layer board (surface heat dissipation copper foil 70mm  70mm) (3) 2-layer board (surface heat dissipation copper foil 15mm  15mm) (4) 1-layer board (surface heat dissipation copper foil 0mm  0mm) Ordering Information B D 9 C 4 Part Number 0 1 E F J Package EFJ: HTSOP-J8 - E2 Packaging and forming specification E2: Embossed tape and reel Marking Diagram (TOP VIEW) HTSOP-J8(TOP VIEW) Part Number Marking D 9 C 4 0 1 LOT Number T Numbe 1PIN MARK www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 18/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Physical Dimension, Tape and Reel Information Package Name www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 HTSOP-J8 19/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 BD9C401EFJ Revision History Date Revision 7.MAR.2013 001 New Release 6.AUG.2013 002 Add Example of evaluation board layout 8.APR.2014 003 Expression change Output Voltage Setting 004 P.8 P.9 P.11 P.14 24.JUL.2018 Changes www.rohm.com © 2013 ROHM Co., Ltd. All rights reserved. TSZ22111 • 15 • 001 Add VIN signal on Figure16. Add the explanation of UVLO and detailed timing chart. Add the description. Add the description. 20/20 TSZ02201-0J2J0AJ00440-1-2 24.JUL.2018 Rev.004 Notice Precaution on using ROHM Products 1. Our Products are designed and manufactured for application in ordinary electronic equipment (such as AV equipment, OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you (Note 1) intend to use our Products in devices requiring extremely high reliability (such as medical equipment , transport equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance. Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific Applications. (Note1) Medical Equipment Classification of the Specific Applications JAPAN USA EU CHINA CLASSⅢ CLASSⅡb CLASSⅢ CLASSⅢ CLASSⅣ CLASSⅢ 2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which a failure or malfunction of our Products may cause. The following are examples of safety measures: [a] Installation of protection circuits or other protective devices to improve system safety [b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure 3. Our Products are designed and manufactured for use under standard conditions and not under any special or extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any special or extraordinary environments or conditions. If you intend to use our Products under any special or extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of product performance, reliability, etc, prior to use, must be necessary: [a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents [b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust [c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2 [d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves [e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items [f] Sealing or coating our Products with resin or other coating materials [g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning residue after soldering [h] Use of the Products in places subject to dew condensation 4. The Products are not subject to radiation-proof design. 5. Please verify and confirm characteristics of the final or mounted products in using the Products. 6. In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied, confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect product performance and reliability. 7. De-rate Power Dissipation depending on ambient temperature. When used in sealed area, confirm that it is the use in the range that does not exceed the maximum junction temperature. 8. Confirm that operation temperature is within the specified range described in the product specification. 9. ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in this document. Precaution for Mounting / Circuit board design 1. When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product performance and reliability. 2. In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method must be used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products, please consult with the ROHM representative in advance. For details, please refer to ROHM Mounting specification Notice-PGA-E © 2015 ROHM Co., Ltd. All rights reserved. Rev.003 Precautions Regarding Application Examples and External Circuits 1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the characteristics of the Products and external components, including transient characteristics, as well as static characteristics. 2. You agree that application notes, reference designs, and associated data and information contained in this document are presented only as guidance for Products use. Therefore, in case you use such information, you are solely responsible for it and you must exercise your own independent verification and judgment in the use of such information contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of such information. Precaution for Electrostatic This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron, isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control). Precaution for Storage / Transportation 1. Product performance and soldered connections may deteriorate if the Products are stored in the places where: [a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2 [b] the temperature or humidity exceeds those recommended by ROHM [c] the Products are exposed to direct sunshine or condensation [d] the Products are exposed to high Electrostatic 2. Even under ROHM recommended storage condition, solderability of products out of recommended storage time period may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is exceeding the recommended storage time period. 3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads may occur due to excessive stress applied when dropping of a carton. 4. Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of which storage time is exceeding the recommended storage time period. Precaution for Product Label A two-dimensional barcode printed on ROHM Products label is for ROHM’s internal use only. Precaution for Disposition When disposing Products please dispose them properly using an authorized industry waste company. Precaution for Foreign Exchange and Foreign Trade act Since concerned goods might be fallen under listed items of export control prescribed by Foreign exchange and Foreign trade act, please consult with ROHM in case of export. Precaution Regarding Intellectual Property Rights 1. All information and data including but not limited to application example contained in this document is for reference only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any other rights of any third party regarding such information or data. 2. ROHM shall not have any obligations where the claims, actions or demands arising from the combination of the Products with other articles such as components, circuits, systems or external equipment (including software). 3. No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any third parties with respect to the Products or the information contained in this document. Provided, however, that ROHM will not assert its intellectual property rights or other rights against you or your customers to the extent necessary to manufacture or sell products containing the Products, subject to the terms and conditions herein. Other Precaution 1. This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM. 2. The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written consent of ROHM. 3. In no event shall you use in any way whatsoever the Products and the related technical information contained in the Products or this document for any military purposes, including but not limited to, the development of mass-destruction weapons. 4. The proper names of companies or products described in this document are trademarks or registered trademarks of ROHM, its affiliated companies or third parties. Notice-PGA-E © 2015 ROHM Co., Ltd. All rights reserved. Rev.003 Datasheet General Precaution 1. Before you use our Products, you are requested to carefully read this document and fully understand its contents. ROHM shall not be in any way responsible or liable for failure, malfunction or accident arising from the use of any ROHM’s Products against warning, caution or note contained in this document. 2. All information contained in this document is current as of the issuing date and subject to change without any prior notice. Before purchasing or using ROHM’s Products, please confirm the latest information with a ROHM sales representative. 3. The information contained in this document is provided on an “as is” basis and ROHM does not warrant that all information contained in this document is accurate and/or error-free. ROHM shall not be in any way responsible or liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccuracy or errors of or concerning such information. Notice – WE © 2015 ROHM Co., Ltd. All rights reserved. Rev.001