BD9B304QWZ-E2 - 3A Sync Buck DC/DC, 2.7-5.5V Input | ROHM
Teilenummer: BD9B304QWZ-E2 ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $1.62 | $1,62 |
| 10 | $1.45 | $14,50 |
| 100 | $1.18 | $118,00 |
| 500 | $0.97 | $485,00 |
| 1.000 | $0.83 | $830,00 |
| 3.000 | $0.72 | $2.160,00 |
BD9B304QWZ-E2 Übersicht
A buck (step-down) DC/DC converter is a switch-mode power supply topology that efficiently converts a higher DC input voltage to a lower DC output voltage by rapidly switching an inductor-capacitor filter network. Buck converters sit within the broader hierarchy of voltage regulators -> DC-DC converters -> power management ICs -> semiconductors, and are preferred over linear regulators whenever (VIN - VOUT) x IOUT would create excessive heat dissipation. The synchronous topology replaces the traditional Schottky rectifier with a second MOSFET to reduce conduction loss.
Key features include a 1.0 MHz / 2.0 MHz selectable switching frequency (set by an external resistor), built-in 40 mOhm high-side and low-side N-channel MOSFETs, constant on-time (COT) control for fast transient response, internal soft-start, and over-current / thermal shutdown protection. The selectable frequency allows the designer to trade efficiency against inductor size.
The COT architecture produces a near-ripple-free output with a small output capacitor and eliminates the compensation network typical of voltage-mode or current-mode PWM parts. High-side and low-side RDSon of 40 mOhm each keep full-load efficiency in the mid-90% range at 5 V to 3.3 V conversion, and the 1 MHz / 2 MHz switching options push the fundamental above the AM band for EMI-sensitive consumer designs.
Typical applications include point-of-load (POL) rails for FPGAs, ASICs, and SoCs, USB Type-C / PD auxiliary supplies, portable battery-powered devices running from a single-cell Li-ion (2.7V-4.2V) or 5V USB rail, solid-state drive (SSD) power management, and HDMI / DisplayPort interface power. The exposed thermal pad of the XFDFN-8 package ties directly to a small ground copper pour for heat extraction.
When designing with the BD9B304QWZ-E2, pay attention to inductor selection - a 1.0 uH to 2.2 uH shielded power inductor is typical for 1 MHz operation. Keep the input/output ceramic capacitors (typically 22 uF X5R or X7R) within 2 mm of the IC pins to minimize parasitic loop inductance that could cause switching-node ringing.
This page synthesizes distributor pricing, parametric drop-in alternatives in the same XFDFN-8 footprint, and practical design notes not found in the manufacturer datasheet alone.
Drop-in-Alternativen für BD9B304QWZ-E2 – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Varianten dieser Serie
Modelle derselben Serie, die drop-in-kompatibel sind mit BD9B304QWZ-E2 (gleiche Bauform und Footprint) – abweichend in Input Voltage Range, Maximum Output Current, Output Voltage Range, Package, Topology.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
BD9B304QWZ
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
BD9B304QWZ-EVK-001
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
BD9B300MUF-CE2
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
BD9B305QWZ
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
TPS62840DLCR
✅ Drop-In✓ Auf Lager
$1.21 / Stück
Datenblatt ansehen →LMR33630
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
BD9B304QWZ-E2 Grenzwerte & elektrische Eigenschaften
| Topologie | Synchronous Buck (Step-Down) |
| Eingangsspannungsbereich | 2.7 V to 5.5 V |
| Ausgangsspannungsbereich | 0.8 V to 0.8 x VIN (adjustable) |
| Maximaler Ausgangsstrom | 3.0 A |
| Schaltfrequenz | 1.0 MHz / 2.0 MHz (selectable via RT pin) |
| High-Side MOSFET RDSon | 40 mOhm |
| Low-Side MOSFET RDSon | 40 mOhm |
| Control Method | Constant On-Time (COT) |
| Anzahl der Ausgänge | 1 |
| Gehäuse | 8-XFDFN Exposed Pad (UMMP008AZ) |
| Montageart | Surface Mount |
| RoHS-Status | Compliant |
| Lead-Free | Yes |
| Built-in Protection | Over-current protection, Thermal shutdown, Soft-start |
BD9B304QWZ-E2 Pin-Konfiguration
| Pin 1 | VIN — Power supply input (2.7V to 5.5V) |
| Pin 2 | SW — Switching node - connection to power inductor |
| Pin 3 | GND — Ground reference |
| Pin 4 | FB — Feedback / output voltage sense (sets VOUT via resistor divider) |
| Pin 5 | EN — Enable input (active high) |
| Pin 6 | RT — Timing resistor for 1 MHz / 2 MHz switching frequency selection |
| Pin 7 | PGND — Power ground - connect to exposed pad |
| Pin 8 | BST — Bootstrap capacitor for high-side gate driver |
Typische Anwendungen
BD9B304QWZ-E2 ist geeignet für 6 Anwendungs: Point-of-Load (POL) Power for FPGA / SoC, USB Type-C / 5V VBUS Power Conversion, Portable / Battery-Powered Devices, Solid-State Drive (SSD) Power Management, HDMI / DisplayPort Interface Power, Industrial Sensor and IoT Edge Modules.
Point-of-Load (POL) Power for FPGA / SoC
The BD9B304QWZ-E2 is well-suited as a 3A point-of-load converter for FPGAs, ASICs, and SoCs that require low-voltage core rails. With its 2.7V-5.5V input and adjustable output from 0.8V to 0.8 x VIN, the device can directly generate typical SoC core voltages such as 1.0V, 1.2V, or 1.8V from a 5V rail. The selectable 1 MHz / 2 MHz switching frequency and constant on-time (COT) control deliver fast transient response, critical for processor cores that step current in microseconds during DVFS transitions. At full 3A load with VIN=5V and VOUT=1.2V, dissipation is approximately 0.5W, well within the XFDFN-8 package's thermal capability when the exposed pad is connected to a 10 mm^2 copper pour.
Empfohlen
USB Type-C / 5V VBUS Power Conversion
The BD9B304QWZ-E2 is ideal for stepping down 5V VBUS from a USB Type-C or USB-PD source to lower voltages required by downstream peripherals. Its 5.5V maximum input safely tolerates the 5.25V upper bound of a USB 5V rail plus cable and connector drop. The 3A output capability can power SSD controllers, hub ICs, or HDMI / DisplayPort interface chips. The 2 MHz switching option places the fundamental above 1 MHz, easing EMI compliance for USB-IF and consumer CE testing, while the COT architecture produces a near-ripple-free output that is gentle on downstream analog blocks. The 2 mm x 2 mm XFDFN-8 footprint is small enough to fit inside a USB Type-C connector housing.
Empfohlen
Portable / Battery-Powered Devices
The BD9B304QWZ-E2 fits naturally into single-cell Li-ion or Li-polymer powered portable products where the input voltage swings from 4.2V (fully charged) down to 2.7V (cutoff). The 2.7V minimum input ensures the converter stays in regulation right down to the battery cutoff, maximizing usable runtime. Its high efficiency (mid-90% at moderate loads) extends battery life, and the COT topology supports 100% duty cycle operation, allowing the output to track the battery directly when VIN approaches VOUT. Quiescent current in the microamp range preserves standby time. The 8-XFDFN package and small 1.0 uH - 2.2 uH inductor deliver a complete solution footprint under 25 mm^2.
Empfohlen
Solid-State Drive (SSD) Power Management
Inside an SSD, the BD9B304QWZ-E2 can generate 3.3V or 1.8V rails from the host's 5V supply for the NAND flash, DRAM cache, and controller. The 3A output is sufficient for high-performance NVMe SSDs that draw 2-2.5A peak during intensive writes. Fast transient response is essential because NAND writes cause sharp load steps; the COT control responds in a single switching cycle. The exposed thermal pad handles the modest dissipation typical of SSD duty cycles. ROHM's reliability pedigree in consumer storage makes the BD9B304QWZ-E2 a common choice for SATA and NVMe SSD power trees in compact M.2 form factors.
Empfohlen
HDMI / DisplayPort Interface Power
HDMI 2.0 / 2.1 transmitters and DisplayPort 1.4 / 2.0 interfaces typically require 3.3V main supply and 1.8V or 1.0V auxiliary rails. The BD9B304QWZ-E2 can generate any of these rails directly from a 5V source. Its low output ripple, resulting from the COT control and small output capacitance, helps meet the tight supply-noise tolerance of high-speed SerDes PHYs. The 2 mm x 2 mm XFDFN package fits under the connector or behind the display panel. Engineers designing 4K / 8K displays commonly use multiple BD9B304QWZ-E2 instances on the same board to power different interface domains independently.
Empfohlen
Industrial Sensor and IoT Edge Modules
In industrial sensor nodes and IoT edge devices, the BD9B304QWZ-E2 provides a clean, regulated rail from a 5V bus or USB supply for MCUs, radios, and sensors. Industrial temperature ranges (typically -40C to +85C or -40C to +125C) require robust thermal performance, which the exposed-pad XFDFN package delivers. The 40 mOhm RDSon keeps efficiency high even at the 3A maximum, reducing heat inside sealed industrial enclosures. The selectable 1 MHz / 2 MHz switching helps avoid interference with sub-GHz or 2.4 GHz radios used in many IoT modules. The 2.7V-5.5V input also accommodates backup battery sources during brown-out events.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für BD9B304QWZ-E2 – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | BD9B304QWZ | BD9B304QWZ-EVK-001 | BD9B300MUF-CE2 | BD9B305QWZ | TPS62840 | LMR33630 |
|---|---|---|---|---|---|---|---|
| Brand | ROHM Semiconductor | ROHM Semiconductor | ROHM Semiconductor | ROHM Semiconductor | ROHM Semiconductor | Texas Instruments | Texas Instruments |
| Package | 8-XFDFN Exposed Pad (UMMP008AZ) | 8-XFDFN Exposed Pad - same | 8-XFDFN Exposed Pad - same | VQFN-8 - different footprint | 8-XFDFN Exposed Pad - same | 8-XFDFN - same 2x2 mm footprint | 8-HSOIC / 8-WSON - different footprint |
| Input Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 3.8 V to 36 V |
| Output Current | 3.0 A | 3.0 A | 3.0 A | 3.0 A | 5.0 A | 3.5 A | 3.0 A |
| Switching Frequency | 1.0 MHz / 2.0 MHz selectable | 1.0 MHz / 2.0 MHz selectable | 1.0 MHz / 2.0 MHz selectable | 1.0 MHz / 2.0 MHz selectable | 1.0 MHz / 2.0 MHz selectable | up to 2.5 MHz | 400 kHz to 2.1 MHz adjustable |
| High-Side RDSon | 40 mOhm | 40 mOhm | 40 mOhm | 40 mOhm | 30 mOhm | 50 mOhm | 75 mOhm |
| Control Method | Constant On-Time (COT) | Constant On-Time (COT) | Constant On-Time (COT) | Constant On-Time (COT) | Constant On-Time (COT) | DCS-Control | Voltage Mode PWM |
| Output Voltage Range | 0.8 V to 0.8 x VIN | 0.8 V to 0.8 x VIN | 0.8 V to 0.8 x VIN | 0.8 V to 0.8 x VIN | 0.8 V to 0.8 x VIN | 0.8 V to 4.0 V | 1.0 V to 24 V |
Wichtigste Unterscheidungsmerkmale
- Selectable 1 MHz / 2 MHz switching frequency (vs. TPS62840)
- Compact 2 mm x 2 mm 8-XFDFN footprint (vs. LMR33630)
- Lower minimum input voltage (2.7V vs 3.8V) (vs. LMR33630)
- COT control yields fast transient response (vs. TPS62840)
Designhinweise
Place the input capacitor (typically 22 uF X5R / X7R 6.3V or higher) within 2 mm of the VIN pin to minimize parasitic loop inductance in the high-frequency switching loop. Connect the exposed thermal pad (PGND) directly to a ground copper pour of at least 10 mm^2 to keep junction temperature within safe operating area at 3A load. Avoid routing signal traces under the switching node (SW pin) to prevent capacitive coupling and noise injection into the feedback loop.
Estimated: at VIN=5V, VOUT=3.3V, IOUT=3A, the converter dissipates approximately (5-3.3) x 3 = 5.1W at 100% efficiency, or roughly 0.3-0.6W at mid-90% efficiency. With the XFDFN-8 exposed pad on a 10 mm^2 copper pour, theta_JA is typically 60-80 C/W, yielding a 25-40 C junction temperature rise above ambient - acceptable for -40C to +85C industrial operation. Reduce VIN-VOUT drop (e.g., to 5V-to-1.8V for an SoC core) or limit maximum load to 2A in sealed enclosures without additional heatsinking.
Do not exceed the 5.5V maximum VIN rating - USB VBUS transients during hot-plug can briefly exceed 6V and damage the IC. Place a TVS diode (e.g., SMAJ5.0A) at the input for USB-powered designs. The bootstrap capacitor (between BST and SW) must be a 0.1 uF ceramic placed within 1 mm of the BST pin; an undersized or distant capacitor causes high-side gate-drive weakness and RDSon degradation. The RT resistor sets switching frequency - do not leave this pin floating or the converter may operate at an undefined frequency.
Route the feedback (FB) trace away from the SW switching node and the power inductor to avoid noise injection that destabilizes the COT loop. Use a Kelvin-sense connection from the output capacitor's positive terminal directly to the FB pin and resistor divider ground, rather than tying the divider ground to a noisy chassis ground. Keep the power inductor and input/output capacitor loop as small and tight as possible - a typical 4-layer board with a continuous ground plane underneath is recommended for EMI compliance.
For 1 MHz operation, use a 1.0 uH - 2.2 uH shielded power inductor rated for at least 4A saturation current and low DCR (under 30 mOhm). For 2 MHz operation, drop to 0.47 uH - 1.0 uH to maintain acceptable inductor ripple. The output capacitor should be 22 uF - 47 uF X5R / X7R with a voltage rating at least 1.5x VOUT. Ceramic capacitors from Murata, TDK, or Samsung are preferred for low ESR and small footprint; do not use low-cost Y5V dielectrics whose capacitance drops 50%+ with applied voltage.
Compliance-Informationen
RoHS and REACH compliance per ROHM product page. Not AEC-Q100 qualified; the part is targeted at consumer / industrial / portable applications rather than automotive. Halogen-free status not explicitly stated in retrieved data; recommend checking the manufacturer's environmental compliance letter for the latest information.
