BD9745EKN-E2 Rohm Semiconductor, BD9745EKN-E2 Datasheet
BD9745EKN-E2
Specifications of BD9745EKN-E2
Related parts for BD9745EKN-E2
BD9745EKN-E2 Summary of contents
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STRUCTURE Silicon Monolithic Integrated Circuit PRODUCT SERIES 7-Channel Switching Regulator Controller for Digital Camera ＢＤ９７４５ＥＫＮ TYPE PACKAGE Fig. 1 (Plastic mold) HQFN-48U package PIN ASSIGNMENT Fig. 2 BLOCK DIAGRAM Fig. 3 APPLICATION CIRCUIT Fig. 4 ● 1.5V Minimum input operating. ...
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Recommended operating conditions Parameter VREF Pin Connect Capacitor VREGA Pin Connect Capacitor SCP Pin Connect Capacitor 【 Oscillator 】 Oscillator Frequency OSC Timing Resistor 【Driver】 P-channel Drain Current(CH1～4) N-channel Drain Current(CH1～4) N-channel Drain Current (CH6) P-channel Drain Current (Load ...
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VCC=5V, RT=62kohm, STB1～7=3V） Parameter Symbol 【 Reference Voltage for CH5 】 Reference Voltage Vref5 Line Regulation DVLi Load Regulation DVLo Short Circuit Output Current Ios 【 Internal Regulator 】 REGA Output Voltage VREGA 【 Low Voltage Input Prevented ...
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VCC=5V, RT=62kohm, STB1～7=3V） Parameter 【 Output Circuit 】 CH1,2,3,4 Pch FET ON Resistor CH1 Nch FET ON Resistor CH2,3,4 Nch FET ON Resistor CH6,7 Load SW ON Resistor CH6 Nch FET ON Resistor OUT5 High-level Output Voltage ON ...
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Notice : Do not use the dotted line area Fig. 1 PACKAGE Fig. 2 PIN ASSIGNMENT REV. D For soldering 5/21 ...
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DESCRIPTION PIN No. NAME PVCC5 33 17-18,6-7,43 PGND12,34,567 30 VREGA 14,20,9,4 Hx1,2,3,4 15-16,19,8,5,44 Lx1 46,40 HS6H, HS7H 45,41 HS6L, HS7L 26,25,27,28,36,38 INV1,2,3,4,6 ...
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REG A To Control Block SCP CMOM1,5,6 2.2V SS STB1 VBAT - Start-Up + ERRCOMP1 OSC 26.INV1 + - + ERRAMP1 0.8V STEP UP/DOWN SELECTOR1 SCPCOMP2 UDSEL1 - + 25.INV2 + - + 0.8V ERRAMP2 ...
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Vo1 INV1 0.8V SCPCOMP2 Vo2 - + INV2 0.8V SCPCOMP3 Vo3 - + INV3 0.8V SCPCOMP4 Vo4 - + INV4 0.8V To ERRAMP VREF VOLTAGE REFERENNCE SS5 NON5 Vo5 Vo6 INV6 0.8V Vo7 INV7 0.8V INV7I 0.4V UVLO SOFT START ...
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Vo1 INV1 Vo2 INV2 SCPCOMP3 Vo3 INV3 SCPCOMP4 Vo4 INV4 To ERRAMP VREF VOLTAGE REFERENNCE NON5 Vo5 Vo6 INV6 Vo7 INV7 INV7I UVLO STB ※ Note The following application circuit is recommended. Make sure to confirm its characteristics. When making ...
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I/O Equivalent Circuit Diagrams Pin. Pin Input / No Name Output 26 INV1 I 25 INV2 I Error amp inverting input pin. 27 INV3 I 28 INV4 I 36 INV6 I 38 INV7 I 37 INV7I I 35 NON5 ...
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Pin. Pin Input / No Name Output 30 VREGA O REGA output voltage VREF O Reference voltage for CH5 UDSEL1 I Step-up/down switching 24 UDSEL2 I mode selection 3 UDSEL4 I H= Step-down L= Step-up 22 VBAT - ...
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Pin. Pin Input / No Name Output 14,20,4 Hx1, 2,4 O 15, -16,19,5 Lx1, 2,4 O 17-18,6-7 PGND12 Hx3 O 8 Lx3 O 21 PVCC - 42 OUT7 PGND567 Description Pch FET source. Nch, ...
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Pin. Pin Input / No Name Output 2 PVCC5 - Power supply for Driver. 1 OUT5 O Connect to the gate of CH5 external Pch FET. 43 PGND567 - Ground. 44 Lx6 O Nch FET Drain. 45 PGND567 - 46,40 ...
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... Inverting voltage of CH5 is following this reference. To prevent any oscillations at the output μ F external capacitor is recommended. 5．OSC The BD9745EKN include a triangular waveform oscillator for voltage-mode PWM controllers, and slope oscillator for current-mode PWM controllers. To set the oscillator frequency, connect a timing resistor to the RT (29 pin). ...
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START , SS1 The circuit prevents inrush current in startup by ramping DC/DC output voltage. The soft-start time of each channel is designed below. a. CH1・・・・・・・Typical IC Design’s output startup time is 4.2msec. Only CH1, the startup time doesn’t ...
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DRIVER This CMOS inverting output circuit is a Driver block with built-in and external Nch FET. PVCC pin voltage for DRIVER must have same voltage with VCC pin voltage for main block. 12．Pch DRIVER This CMOS inverting output circuit ...
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APPLICATION INFORMATION １.) CH1 Start up sequence. Using step up function in CH1, please take below measure to prevent operation faults and destruction on start-up. ａ：CH1 output input to VCC It must be put schottky Di between Lx1 and ...
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Applying condition of VBAT voltage. The up/down selector UDSEL1,2,4 is constructed by inverter circuit whose power is VBAT, therefore it is possible that operation faults is happen to apply STB voltage without applying VBAT voltage rule, VBAT ...
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Built-in Pch FET(CH1～4,CH67),the drop of current ability in low battery voltage situation The ON resistance of the built-in Pch FET increase because the FET operates in the saturation region below VGS=1.3V. Therefore when CH6, 7 step-up converter or step-down ...
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Setting the output voltage. a. Setting for positive to negative converter (CH5). The reference of CH5 Error AMP is internally connected to ground. So the high accuracy regulator can be formed up to set up a resistor divider to ...
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Notes １.) Absolute maximum ratings This product is produced with strict quality control. However, the IC may be destroyed if operated beyond its absolute maximum ratings. If the device is destroyed by exceeding the recommended maximum ratings, the failure ...
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No copying or reproduction of this document, in part or in whole, is permitted without the 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 ...