Datasheet 4.2V to 18V, 2A 1ch Synchronous Buck Converter with Integrated FET BD9328EFJ General Description Key Specifications The BD9328EFJ is a synchronous step-down switching regulator with built-in two low-resistance N-Channel MOSFETs. This IC can supply continuous output current of 2A over a wide input range, and provides not only fast transient response, but also easy phase compensation because of current mode control. Input Voltage Range: 4.2V to 18V Output Voltage Range: 0.9V to (VIN x 0.7)V Output Current: 2A (Max) Switching Frequency: 380kHz(Typ) Hi-Side FET ON-Resistance: 0.15Ω(Typ) Lo-Side FET ON-Resistance: 0.13Ω(Typ) Standby Current: 15μA (Typ) Operating Temperature Range: -40°C to +85°C Features Uses Low ESR Output Ceramic Capacitors Low Standby Current 380 kHz Fixed Operating Frequency Feedback Voltage 0.9V ± 1.5%(Ta=25°C) 0.9V ± 2.0%(Ta=-25°C to +85°C) Under Voltage Protection Thermal Shutdown Over Current Protection W (Typ) Package D (Typ) H (Max) Applications Distributed Power Systems Pre-Regulator for Linear Regulators HTSOP-J8 4.90mm x 6.00mm x 1.00mm Typical Application Circuit C_PC 3300pF R_PC 7.5kΩ R_DW 10kΩ R_UP 27kΩ FB COMP EN SS C_SS 0.1μF Thermal Pad GND SW BST VIN (to be shorted to GND) VIN = 12V L VOUT = 3.3V 10µH C_BS 0.1μF R_BS 22Ω C_VC1 10μF C_CO1 20μF R_BS protect from VIN-BST short destruction. Figure 1. Typical Application Circuit 〇Product structure : Silicon monolithic integrated circuit www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・14・001 〇This product has no designed protection against radioactive rays 1/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Pin Configuration Block Diagram (TOP VIEW) SS EN COMP FB BST VIN SW GND VIN Figure 2. Pin Configuration Figure 3. Block Diagram Pin Description Pin No. Pin Name 1 BST High-side gate drive boost input 2 VIN Power input 3 SW 4 GND Function Power switching output Ground 5 FB 6 COMP 7 EN Enable input 8 SS Soft start control input www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111･15･001 Feedback input Compensation node 2/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Absolute Maximum Ratings (Ta = 25°C) Parameter Symbol Rating Unit Supply Voltage VIN 20 V Switch Voltage VSW 20 V Power Dissipation for HTSOP-J8 Pd Package Thermal Resistance θja (Note 2) θja 3.76 (Note 1) W 29.27 °C /W Package Thermal Resistance θjc (Note 2) θjc 3.75 °C /W Operating Temperature Range Topr -40 to +85 °C Storage Temperature Range Tstg -55 to +150 °C Tjmax 150 °C VBST VSW+7 V EN Voltage VEN 20 V All Other Pins VOTH 20 V Maximum Junction Temperature BST Voltage (Note 1) Derating is done 30.08 mW/°C when operating above Ta ≥ 25°C (Mount on 4-layer 70.0mm x 70.0mm x 1.6mm board) (Note 2) Mount on a 4-layer 50mm x 30mm x 1.6mm application board 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 Conditions (Ta= -40°C to +85°C) Parameter Symbol Rating Unit Min Typ Max 12 18 V Supply Voltage VIN 4.2 SW Voltage VSW -0.5 - +18 V Output Current ISW3 - - 2 A VRANGE 0.9 - VIN x 0.7 V Output Voltage Range Electrical Characteristics (Unless otherwise specified VIN=12V Ta=25°C) Parameter Symbol Limit Unit Conditions Min Typ Max IFB - 0.02 2 µA Feedback Voltage1 VFB1 0.886 0.900 0.914 V Voltage Follower Feedback Voltage2 VFB2 0.882 0.900 0.918 V Ta=-25°C to +85°C Hi-Side FET ON-Resistance RONH - 0.15 - Ω ISW= -0.8A Lo-Side FET ON-Resistance RONL - 0.13 - Ω Hi/Lo-Side FET Leak Current ILEAKN - 0 10 µA ISW= 0.8A VIN= 18V, VSW= 0V / 18V Switch Current Limit ILIMIT3 3 - - A Maximum Duty Cycle MDUTY - 90 - % VFB= 0V VEN= 12V Error Amplifier Block FB Input Bias Current SW Block – SW General Enable Sink Current IEN 90 180 270 µA Enable Threshold Voltage VEN 1.0 1.2 1.4 V Under Voltage Lockout Threshold VUVLO 3.5 3.75 4.0 V Under Voltage Lockout Hysteresis VHYS - 0.3 - V ISS 5 10 15 µA VSS= 0 V CSS= 0.1 µF Soft Start Current VIN Rising Soft Start Time tSS - 22 - ms Operating Frequency fOSC 300 380 460 kHz Circuit Current ICC - 1.2 3 mA VFB= 1.5V, VEN= 12V Standby Current IQUI - 15 27 µA VEN= 0V www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 3/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Typical Performance Curves ICC (µA) ICC (mA) (Unless otherwise specified, VIN= 12V Ta= 25°C) VIN (V) VIN (V) Figure 4. Circuit Current vs Input Voltage (No Switching) IFB (µA) Figure 5. Standby Current vs Input Voltage (Shutdown Mode) VFB (V) Temperature [°C] Figure 6. Input Bias Current vs Feedback Voltage www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 Figure 7. Feedback Voltage vs Temperature 4/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Typical Performance Curves - continued 390 385 RON [Ω] fOSC (kHz) FOSC (kHz) 380 375 370 365 360 -4 0 Temperature [°C] -2 0 0 20 40 60 80 T E M P ( °C[°C] ) Temperature Figure 8. Hi-Side, Low-Side FET ON-Resistance vs Temperature Figure 9. Operating Frequency vs Temperature 95 90 Soft Start Time [ms] 85 Efficiency Efficiency[%] 80 75 70 65 60 55 50 0 500 1000 1500 2000 IOIo[mA] [mA] CSS [µF] Figure 10. STEP-Down Efficiency vs IO (VIN= 12V VOUT= 3.3V L=10µH) www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 Figure 11. Soft Start Time vs Soft Start Capacitor 5/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Typical Waveforms VOUT IOUT Figure 13. Transient Response (VIN= 12V VOUT= 3.3V L= 10µH COUT =20µF IOUT= 0.2-1.0A ) Figure 12. Over Current Protection (VOUT is shorted to GND) Figure 14. Output Ripple Voltage (VIN= 12V VOUT= 3.3V L= 10µH COUT =20µF IOUT= 1.0A ) www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 6/19 Figure 15. Transient Response (VIN= 12V VOUT= 3.3V L= 10µH COUT =20µF IOUT= 0.2-2.0A) TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Typical Waveforms - continued tSS Figure 16. Output Ripple Voltage (VIN= 12V VOUT= 3.3V L= 10µH COUT =20µF IOUT= 2.0A ) www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 7/19 Figure 17. Start-Up Waveform (VIN= 12V VOUT= 3.3V L= 10µH CSS= 0.1µF) TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Application Information 1. Typical Application Circuit C_PC 3300pF R_PC 7.5kΩ R_DW 10kΩ R_UP 27kΩ FB COMP EN SS C_SS 0.1μF Thermal Pad VIN = 12V GND SW VIN BST (to be shorted to GND) L VOUT = 3.3V 10µH C_CO1 20μF C_BS 0.1μF R_BS 22Ω C_VC1 10μF R_BS protect from VIN-BST short destruction. Figure 18. Typical Application Circuit Symbol Maker Part No Input Capacitor C_VC1 TDK C3225JB1E106K 10µF/25V Output Capacitor C_CO1 TDK C3216JB1C106M 10µF/16V Inductor L TDK SLF10165-100M3R8 10µH/3.8A www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 8/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ 2. Block Operation (1) VREG This block generates a constant voltage for DC/DC boosting. (2) VREF This block generates an internal reference voltage of 5.1 V (Typ). (3) TSD/UVLO TSD (Thermal shutdown)/UVLO (Under Voltage Lockout) protection block. The TSD circuit shuts down the IC at high temperature. The UVLO circuit shuts down the IC when the VIN voltage is low. (4) Error Amp Block (ERR) This block compares the reference voltage and the feedback voltage from the output. The output voltage of this block, which is connected to COMP pin, determines the switching duty cycle. At the time of startup, since the soft start is operated by the SS pin voltage, the COMP pin voltage is limited to the SS pin voltage. (5) Oscillator Block (OSC) This block generates the oscillating frequency. (6) SLOPE Block This block generates the triangular waveform with the use of the clock created by OSC. The generated triangular waveform is sent to the PWM comparator. (7) PWM Block The COMP pin voltage output of the error amp is compared to the SLOPE block's triangular waveform to determine the switching duty. Since the switching duty cycle is limited by the maximum duty ratio which is determined internally, 100% duty cycle cannot be achieved. (8) DRV Block A DC/DC driver block that accepts signal from the PWM block to drive the power FETs. (9) OCP Block OCP (Over Current Protection) block. The current that flows through the FETs is detected, and OCP starts when it reached 3.0A (min). After OCP detection, switching is turned off and the SS capacitor is discharged. OCP is not a “latch type” but an “auto restart”. (10) Soft Start Circuit This circuit prevents output voltage overshoot or inrush current by making the output voltage rise gradually while restricting the current at the time of startup. www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 9/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ 3. Selecting Application Components (1) Output LC Filter Constant Selection (Buck Converter) The Output LC filter is required to supply constant current to the output load. A larger inductance value at this filter results in less inductor ripple current (∆IL) and less output ripple voltage. However, inductors with large values tend to have slower load transient-response, a larger physical size, a lower saturation current, and a higher series resistance. A smaller value of inductance has almost opposite characteristics as above. So, choosing the Inductor ripple current (∆IL) between 20% to 40% of the averaged inductor current (equivalent to the output load current) is a good compromise. ∆IL /2 IOUTMAX + I should not reach the rated value level IILL VIN VOUT ILR Inductor averaged current L COUT t Figure 19 Figure 20 Setting ∆IL = 30% x Averaged Inductor Current (2A) = 0.6 [A] L VOUT VIN VOUT 1 VIN f OSC I L 10 H Where: VIN= 12V, VOUT= 3.3V, fosc= 380 kHz, fosc is the switching frequency Also the inductor should have a higher saturation current than IOUTMAX + ∆IL / 2. The output capacitor COUT affects the output ripple-voltage. Choose a high-value capacitor to achieve a smaller ripple-voltage that is enough to meet the application requirement. Output ripple voltage ∆VRPL is calculated using the following equation: 1 V RPL I L R ESR C 8 OUT f OSC V where: RESR is the parasitic series resistance of the output capacitor. Setting COUT = 20µF, RESR = 10mΩ VRPL 0.6 (10 m 1 /(8 20 380k )) 15.8mV (2) Loop Compensation Choosing compensation capacitor CCMP and resistor RCMP The current-mode buck converter has 2-poles and 1-zero system. Choosing the appropriate compensation resistor and capacitor is important to achieve a good load-transient response and good stability. An example of a DC/DC converter application bode plot is shown in Figure 22. The compensation resistor, RCMP, determines the cross over frequency FCRS (the frequency at which the total DC-DC loop-gain falls to 0dB). Setting a higher cross-over frequency achieves good response speed, but less stability. On the other hand, setting the cross-over frequency to a lower value may result to better stability, but poorer response speed. Setting the cross-over frequency to 1/10 of the switching frequency shows good performance at most applications. www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 10/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ (a) Choosing phase compensation resistor RCMP The compensation resistor RCMP can be calculated by the following formula: RCMP 2 VOUT f CRS COUT VFB GMP GMA Where: VOUT is the Output voltage fCRS is the Cross over frequency COUT is the Output capacitor VFB is the Internal feedback voltage (0.9V(TYP)) GMP is the Current Sense Gain (7.8A/V(TYP)) GMA is the Error Amplifier Trans-conductance (300µA/V(TYP)) Setting VOUT= 3.3V, fCRS= 38kHz, COUT= 20µF; RCMP 2 3.3 38k 20 7482 .5 7.5k 0.9 7.8 300 [ ] (b) Choosing phase compensation capacitor CCMP For stability of the DC/DC converter, cancellation of the phase delay that derives from output capacitor COUT and resistive load ROUT is possible by inserting the phase advance. The phase advance can be added by the zero on compensation resistor RCMP and capacitor CCMP. Making fZ= fCRS / 6 gives a first-order estimate of CCMP. Compensation Capacitor CCMP 1 2 RCMP fz F Setting fZ= fCRS/6 = 6.3kHz; Compensation Capacitor C CMP 1 2 RCMP 6.3k 3.368 10 9 3.3 10 9 [F ] However, the best values for zero and FCRS differ between applications. Decide the values accordingly after calculation using the formula above and confirmation on the actual application. (c) The condition of the loop compensation stability The stability of DC/DC converter is important. To ensure operation stability, check if the loop compensation has enough phase-margin. For the condition of loop compensation stability, the phase-delay must be less than 150 degrees at 0 dB Gain. Feed-forward capacitor, CRUP, boosts phase margin over a limited frequency range and is sometimes used to improve loop response. CRUP will be more effective if RUP >> RUP||RDW V OUT A (a) Gain [dB] C RUP R UP FB GBW(b) COMP － 0 ＋ R DW R CMP 0.9V C CMP Phase PHASE F CRS fFCRS 0 －90° －90 PhaseMARGIN Margin PHASE －180° －180 Figure 21 F Figure 22 (3) Design of Feedback Resistance constant Set the feedback resistance as shown below. 0.9V VOUT VOUT R1 R 2 0.9 R2 [V ] + R1 ERR FB － R2 Figure 23 www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 11/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ 4. Soft Start Function ERRAMP ISS 10µA ↓ COMP SS + + An adjustable soft-start function to prevent high inrush current during start-up is available. The soft-start time is set by the external capacitor connected to SS pin. The soft start time is given by t SS s 2.2 C SS / I SS CSS - The charge time of CSS t SS 1 s 0.6 C SS / I SS Figure 24 The SS terminal rising time t SS 2 s 1.6 C SS / I SS Setting CSS= 0.1µF t SS [ s ] (0.6 1.6) 0.1 / 10 22 [ ms ] Please confirm the overshoot of the output voltage and inrush current in deciding the SS capacitor value. 5. EN Function VIN EN The EN terminal controls the IC’s shut down. Leaving EN terminal open shuts down the IC. To start the IC, the EN terminal should be connected to VIN or to another power source. When the EN voltage exceeds 1.2V (typ), the IC starts operating. 66 kΩ(typ) 91 kΩ(typ) RREN EN EN (Attention) If the falling edge of EN input is too slow, output chattering occurs. This may cause large inverse current from output to input to flow and VIN voltage to increase, leading to destruction of the IC. Thus, set the fall time of EN signal within 100µs when controlling the ON/OFF operation of the IC. This requirement is not needed when EN pin is connected with VIN and EN is not controlled. ON/OFF Signal As a recommendation, control EN with an open drain MOSFET connected as shown on Figure 25. Figure 25 www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 12/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ 6. Layout Pattern Consideration Two high pulsing current loops exist in the buck regulator system. The first loop, when FET is ON, starts from the input capacitors, to the VIN terminal, to the SW terminal, to the inductor, to the output capacitors, and then returns to the input capacitor through GND. The second loop, when FET is OFF, starts from the low FET, to the inductor, to the output capacitor, and then returns to the low FET through GND. To reduce the noise and improve the efficiency, please minimize these two loop areas. The input capacitor, output capacitor and the low FET should be connected to the PCB’s GND plain. PCB Layout may greatly affect the thermal performance, noise and efficiency. So please take extra care when designing PCB Layout patterns. L VIN CIN FET VOUT COUT Figure 26. Current Loop in Buck Regulator System (1) The thermal Pad on the back side of the IC has the greatest thermal conduction into the chip. So using the GND plane as broad and wide as possible can help thermal dissipation. Adding thermal via for dissipation of heat into the different layers is also effective. (2) The input capacitors should be connected as close as possible to the VIN terminal. (3) When there is an unused area on the PCB, please arrange the copper foil plain of DC nodes, such as GND, VIN and VOUT for better heat dissipation of the IC or circumference parts. (4) To avoid the noise influence from AC coupling with the other lines, keep the switching lines such as SW as short as possible, and coil traces as short and as thick as possible. (5) Keep sensitive signal traces such as traces connected to FB and COMP away from SW pin. (6) The inductor and the output capacitors should be placed close to SW pin as much as possible. CIN L BST SS VIN EN SW COMP GND FB COUT VOUT Figure 27. An example of PCB Layout Pattern www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 13/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ I/O Equivalence Circuit 1.BST 3.SW VIN 5.FB VIN VIN REG SW 6.COMP VIN 7.EN 8.SS VIN VIN VIN Figure 28. I/O Equivalence Circuit Power Dissipation : Pd [mW] POWER DISSIPATION: PD [mW] Power Dissipation 4000 HTSOP-J8 Package On 70mm x 70mm x 1.6 mm glass epoxy PCB (4)3760mW (1) 1-layer board (Backside copper foil area 0 mm x 0 mm) (2) 2-layer board (Backside copper foil area 15 mm x 15 mm) (3) 2-layer board (Backside copper foil area 70 mm x 70 mm) (4) 4-layer board (Backside copper foil area 70 mm x 70 mm) 3000 (3)2110mW 2000 (2)1100mW 1000 (1)820mW 0 0 25 50 75 100 125 150 AmbientTEMPERATURE: Temperature : Ta Ta [°C] AMBIENT [°C] www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 14/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ 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 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 © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 15/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ 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. Figure 29. Example of monolithic IC structure 13. 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. 14. 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. 15. EN control speed Chattering happens if standing lowering speed is slow when standing of EN pin is lowered. The reverse current in which the input side and the pressure operation are done from the output side is generated when chattering operates with the output voltage remained, and there is a case to destruction. Please set to stand within 100us when you control ON/OFF by the EN signal. 16. About output voltage when EN terminal on When restarting by EN terminal, BD9328EFJ starts from 0V. When an electric charge is left in an output capacitance at this time, electric current discharge from an output capacitance is performed. When many electric charges are left in an output capacitance, this electrical current discharge becomes big, and BD9328EFJ sometimes comes to destruction. Therefore please do the discharge control to follow conditions of output voltage when EN terminal on. In case of output capacitor value is less than 100 μF,: Please set the output voltage less than 2.0V when EN terminal on. In case of output capacitor value is more than 100 μF,: Please set the output voltage based on the next formula. (Output voltage when EN terminal on [V]) < www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 9.15 x ( Output capacitance [μF] ) 16/19 (-0.33) TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Ordering Information B D 9 3 2 8 E F J Package EFJ : HTSOP-J8 Part Number - E2 Packaging and forming specification E2: Embossed tape and reel Marking Diagram HTSOP-J8(TOP VIEW) Part Number Marking D 9 3 2 8 LOT Number 1PIN MARK www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 17/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Physical Dimension Tape and Reel Information Package Name HTSOP-J8 <Tape and Reel information> Tape Embossed carrier tape Quantity 2500pcs Direction of feed E2 The direction is the 1pin of product is at the upper left when you hold ( reel on the left hand and you pull out the tape on the right hand Direction of feed 1pin Reel www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 ) ∗ Order quantity needs to be multiple of the minimum quantity. 18/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet BD9328EFJ Revision History Date Revision 11.Apr.2012 02.Sep.2014 16.Feb.2015 001 002 003 Changes New Release Applied the ROHM Standard Style and improved understandability. Add “16.about output voltage when EN terminal on” in Operational Notes www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 19/19 TSZ02201-0323AAJ00020-1-2 16.Feb.2015 Rev.003 Datasheet Notice Precaution on using ROHM Products 1. Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment, OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you (Note 1) , transport intend to use our Products in devices requiring extremely high reliability (such as medical equipment 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 (Pd) depending on Ambient temperature (Ta). When used in sealed area, confirm the actual ambient 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-GE © 2013 ROHM Co., Ltd. All rights reserved. Rev.004 Datasheet 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 QR code 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 our Products might fall under controlled goods prescribed by the applicable foreign exchange and foreign trade act, please consult with ROHM representative 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. ROHM shall not be in any way responsible or liable for infringement of any intellectual property rights or other damages arising from use of such information or data.: 2. 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 information contained in this document. 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-GE © 2013 ROHM Co., Ltd. All rights reserved. Rev.004 Datasheet General Precaution 1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents. ROHM shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny ROHM’s Products against warning, caution or note contained in this document. 2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s representative. 3. The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or concerning such information. Notice – WE © 2015 ROHM Co., Ltd. All rights reserved. Rev.001