BD9C401EFJ
Synchronous Buck ConverterThe BD9C401EFJ is a synchronous buck converter from ROHM. View the full BD9C401EFJ datasheet below including key specifications, electrical characteristics, absolute maximum ratings.
Manufacturer
ROHM
Category
Synchronous Buck Converter
Key Specifications
| Parameter | Value |
|---|---|
| Output Current | 4A |
| Switching Frequency | 500kHz |
| Function | Step-Down |
| Height - Seated (Max) | 1 mm |
| Lead Free | Lead Free |
| Length | 4.9 mm |
| Lifecycle Status | Production (Last Updated: 5 months ago) |
| Max Input Voltage | 18 V |
| Max Operating Temperature | 85 °C |
| Max Output Current | 4 A |
| Max Output Voltage | 12.6 V |
| Max Switching Frequency | 550 kHz |
| Min Input Voltage | 4.5 V |
| Min Operating Temperature | -40 °C |
| Min Output Voltage | 562.5 mV |
| Min Supply Voltage | 4.5 V |
| Mount | Surface Mount |
| Mounting Type | Surface Mount |
| Nominal Input Voltage | 12 V |
| Number of Channels | 1 |
| Number of Circuits | 1 |
| Number of Outputs | 1 |
| Number of Outputs | 1 |
| Number of Pins | 8 |
| Number of Terminals | 8 |
| Operating Supply Voltage | 18 V |
| Operating Temperature | -40°C ~ 85°C (TA) |
| Output Configuration | Positive |
| Output Configuration | Positive |
| Output Current | 4 A |
| Output Type | Adjustable |
| Output Type | Adjustable |
| Package / Case | 8-SOIC (0.154", 3.90mm Width) Exposed Pad |
| Packaging | MouseReel |
| Packaging | Cut Tape |
| REACH SVHC | Yes |
| RoHS | Compliant |
| Schedule B | 8542390000 |
| Standard Pack Qty | 2500 |
| Supplier Device Package | 8-HTSOP-J |
| Synchronous Rectifier | Yes |
| Synchronous Rectifier | Yes |
| Terminal Pitch | 1.27 mm |
| Topology | Buck |
| Topology | Buck |
| Input Voltage (Max) | 18V |
| Input Voltage (Min) | 4.5V |
| Output Voltage (Max) | 12.6V |
| Output Voltage | 0.8V |
| Width | 3.9 mm |
Overview
Part: BD9C401EFJ — ROHM Semiconductor
Type: Synchronous Buck DC/DC Converter
Description: 4.5–18 V input, 4 A synchronous buck switching regulator with built-in low on-resistance power MOSFETs, current mode control, and fixed soft start function.
Operating Conditions:
- Supply voltage: 4.5–18.0 V
- Operating temperature: -40 to +85 °C
- Maximum output current: 4.0 A
- Output voltage setting range: VIN × 0.125 to VIN × 0.7 V (VIN × 0.125 ≥ 0.8 V)
Absolute Maximum Ratings:
- Max supply voltage: 20 V
- Max SW pin voltage: 20 V
- Max EN pin voltage: 20 V
- Max junction temperature: 150 °C
- Max storage temperature: -55 to +150 °C
Key Specs:
- Reference voltage: 0.8 V ± 1%
- Switching frequency: 500 kHz (Typ)
- High Side FET On Resistance: 65 mΩ (Typ, VIN = 12V, ISW = -1A)
- Low Side FET On Resistance: 35 mΩ (Typ, VIN = 12V, ISW = -1A)
- Standby current: 1.0 μA (Typ, VEN = 0V)
- Circuit current in active: 1.5 mA (Typ, VFB = 0.75V, VEN = 5V)
- Current limit: 4.5 A (Min)
- Soft Start Time: 1.0 msec (Typ)
Features:
- Synchronous Single DC/DC Converter
- Over Current Protection
- Thermal Shutdown Protection
- Under Voltage Lockout Protection
- Short Circuit Protection
- Fixed Soft Start Function
Applications:
- LCD TVs
- Set-top Boxes
- DVD/Blu-ray Disc Players/Recorders
- Broadband Network and Communication Interface
- Entertainment Devices
Package:
- HTSOP-J8 (E-Pad for heat dissipation)
Features
- ■ Synchronous Single DC/DC Converter
- ■ Over Current Protection
- ■ Thermal Shutdown Protection
- ■ Under Voltage Lockout Protection
- ■ Short Circuit Protection
- ■ Fixed Soft Start Function
Applications
- ■ LCD TVs
- ■ Set-top Boxes
- ■ DVD/Blu-ray Disc Players/Recorders
- ■ Broadband Network and Communication Interface
- ■ Entertainment Devices
Pin Configuration
Figure 2. Pin Assignment
Electrical Characteristics
(Ta = 25 C, VIN = 12 V, VEN = 5 V unless otherwise specified)
| Parameter | Symbol | Limits | Limits | Limits | Unit | Conditions |
|---|---|---|---|---|---|---|
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions |
| Circuit Current in Active | I Q_active | - | 1.5 | 2.5 | mA | V FB = 0.75V, V EN = 5V |
| Circuit Current in Standby | I Q_stby | - | 1.0 | 10.0 | μA | V EN = 0V |
| FB Pin Voltage | V FB | 0.792 | 0.800 | 0.808 | V | FB-COMP Short (Voltage follower) |
| FB Input Current | I FB | - | 0 | 2 | μA | |
| Switching Frequency | f OSC | 450 | 500 | 550 | kHz | |
| High Side FET On Resistance | R ONH | - | 65 | - | mΩ | V IN = 12V , I SW = -1A |
| Low Side FET On Resistance | R ONL | - | 35 | - | mΩ | V IN = 12V , I SW = -1A |
| Power MOS Leakage Current | I LSW | - | 0 | 5 | μA | V IN = 18V , V SW = 18V |
| Current Limit | I LIMIT | 4.5 | - | - | A | |
| Minimum Duty Ratio | Min_duty | - | - | 12.5 | % | |
| UVLO Threshold | V UVLO | 3.75 | 4.0 | 4.25 | V | V IN Sweep up |
| UVLO Hysteresis Voltage | V UVLOHYS | - | 0.2 | - | V | |
| EN High-Level Input Voltage | V ENH | 2.0 | - | - | V | |
| EN Low-Level Input Voltage | V ENL | - | - | 0.8 | V | |
| Soft Start Time | T SS | 0.5 | 1.0 | 2.0 | msec |
(Note 2) Current capability should not exceed Pd.
Absolute Maximum Ratings
| Parameter | Symbol | Rating | Unit | Conditions |
|---|---|---|---|---|
| Supply Voltage | V IN | 20 | V | |
| SW Pin Voltage | V SW | 20 | V | |
| EN Pin Voltage | V EN | 20 | V | |
| Power Dissipation (Note 1) | Pd | 3.76 | W | When mounted on a 70mm x 70 mm x 1.6 mm4-layer glass epoxy board |
| Operating Temperature Range | Topr | -40 to +85 | °C | |
| Storage Temperature Range | Tstg | -55 to +150 | °C | |
| Maximum Junction Temperature | Tjmax | 150 | °C | |
| FB, COMP Pin Voltage | VLVPINS | 7 | V |
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
| Parameter | Symbol | Rating | Rating | Rating | Unit |
|---|---|---|---|---|---|
| Min | Typ | Max | |||
| Supply Voltage | V IN | 4.5 | - | 18.0 | V |
| Output Current | I OUT | - | - | 4.0 | A |
| Output Voltage Setting Range | V RANGE | V IN × 0.125 (Note 1) | - | V IN × 0.7 | V |
(Note 1) VIN x 0.125 ≥ 0.8 [V]
Thermal Information
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
HG : Hi side FET GATE signal
LG : Low side FET GATE signal
Typical Application
Figure 1. Application Circuit
Product structure: silicon monolithic integrated circuit
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This product has no protection against radioactive rays
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Related Variants
The following components are covered by the same datasheet.
| Part Number | Manufacturer | Package |
|---|---|---|
| BD9C401EFJ-E2 | ROHM | 8-SOIC (0.154", 3.90mm Width) Exposed Pad |
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