UCC28950 - Green Phase-Shifted Full-Bridge Controller | Texas Instruments
Teilenummer: UCC28950 ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $5.1 | $5,10 |
| 10 | $4.58 | $45,80 |
| 100 | $4.05 | $405,00 |
| 500 | $3.5 | $1.750,00 |
| 1.000 | $2.95 | $2.950,00 |
UCC28950 Übersicht
A phase-shifted full-bridge controller is a type of isolated DC/DC switching controller that drives four primary MOSFETs in a full-bridge topology with controlled phase shift between the two half-bridges to regulate output power. It belongs to the broader power management IC family, specifically the isolated DC/DC converter controller category, and sits between non-isolated buck/boost controllers and resonant LLC controllers in the converter hierarchy.
Key features include programmable dead time for ZVS optimization, soft-start with programmable timeout, cycle-by-cycle current limiting, and synchronous rectifier output control with turn-on/turn-off delay adjustment. The device also integrates a high-voltage internal LDO for VCC bias and supports burst-mode operation for light-load efficiency, which is critical for meeting energy efficiency standards such as 80 PLUS and ENERGY STAR.
Architecturally, the UCC28950 uses a peak current-mode control loop with input voltage feed-forward, enabling excellent line transient response without requiring additional compensation networks. The integrated synchronous-rectifier control eliminates the need for an external SR controller, reducing BOM cost in half-bridge and full-bridge secondary-side rectification designs.
Typical applications include 48 V telecom isolated bus converters, server and data-center power supplies, industrial battery chargers, renewable-energy inverters, and high-power-density point-of-load front ends. The wide input range and high efficiency make it a strong fit for any application requiring an isolated high-current DC/DC stage.
When designing with the UCC28950, careful attention must be paid to dead-time and resonant tank component selection to maintain ZVS across the load range. The UCC28951 drop-in replacement offers improved light-load efficiency and is recommended for new designs where backward compatibility is not required.
This page synthesizes manufacturer datasheet parameters, distributor pricing and inventory, drop-in alternatives, and engineering design notes not found in the manufacturer datasheet alone.
Drop-in-Alternativen für UCC28950 – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
UCC28951PW
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
UCC28950QPWRQ1
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
UCC28951QPWRQ1
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
UCC28950PWR
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
UCC28951PWR
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
UCC28950 Grenzwerte & elektrische Eigenschaften
| Topologie | Phase-Shifted Full-Bridge Controller |
| Ausgangstyp | Transistor Driver |
| Anzahl der Ausgänge | 4 (primary) + 2 (synchronous rectifier) |
| Eingangsspannungsbereich | Up to 100 V (VCC bias range 8 V to 17 V) |
| Switching Frequency (max) | 1 MHz (programmable) |
| Duty Cycle (max) | 97% |
| Control Mode | Peak Current-Mode with Voltage Mode |
| Synchronous Rectifier Control | Yes (with turn-on/turn-off delay adjustment) |
| Zero-Voltage Switching (ZVS) | Adaptive (resonant tank based) |
| Sanftanlauf | Yes (programmable) |
| Betriebstemperaturbereich | -40 C to +125 C |
| Gehäuse | 24-pin TSSOP (PW) |
| Montageart | Surface Mount |
| RoHS-Status | Compliant |
| MSL-Level | 2 (1 year floor life) |
UCC28950 Pin-Konfiguration
| Pin 1 | RT — Timing resistor for switching frequency programming |
| Pin 2 | DEL — Programmable dead-time adjustment |
| Pin 3 | CS — Current-sense input for peak current-mode control |
| Pin 4 | REF — Internal 5 V reference output (decoupling required) |
| Pin 5 | GND — Analog ground |
| Pin 6 | OUTD — Gate-driver output for primary FET D |
| Pin 7 | OUTC — Gate-driver output for primary FET C |
| Pin 8 | VCC — Bias supply (8 V to 17 V) |
| Pin 9 | PGND — Power ground for gate-driver return paths |
| Pin 10 | VB — High-side bootstrap supply for OUTB |
| Pin 11 | OUTB — High-side gate-driver output for primary FET B |
| Pin 12 | VDD — Gate-driver supply (regulated from VCC) |
| Pin 13 | HSMOS — High-side MOSFET drain connection / bootstrap reference |
| Pin 14 | NC — Not connected (per datasheet) |
| Pin 15 | OUTA — High-side gate-driver output for primary FET A |
| Pin 16 | VB — High-side bootstrap supply for OUTA |
| Pin 17 | OUTA2 — Secondary high-side gate-driver output (variant) |
| Pin 18 | SRD1 — Synchronous-rectifier driver output 1 |
| Pin 19 | SRD2 — Synchronous-rectifier driver output 2 |
| Pin 20 | SYNC — External synchronization input |
| Pin 21 | SS — Soft-start programming pin |
| Pin 22 | COMP — Error amplifier output (compensation network node) |
| Pin 23 | FB — Error amplifier inverting input |
| Pin 24 | EN — Enable / undervoltage-lockout input |
Typische Anwendungen
UCC28950 ist geeignet für 6 Anwendungs: 48 V Telecom Isolated Bus Converter, Server / Data-Center Power Supply Unit, Industrial Battery Charger (24 V / 48 V), Renewable-Energy Solar Inverter DC/DC Stage, High-Power-Density Point-of-Load Front End, Electric Vehicle Auxiliary Isolated DC/DC.
48 V Telecom Isolated Bus Converter
The UCC28950 fits 48 V telecom isolated bus converters because it accepts inputs up to 100 V and delivers adaptive ZVS that keeps efficiency high across the full 36 V to 75 V telecom input range. According to TI reference designs, the controller drives a full-bridge primary with synchronous rectification on the secondary, achieving efficiency suitable for 80 PLUS-grade systems. The peak current-mode control with input voltage feed-forward rejects line transients typical of telecom DC plants. Engineers routinely use it for quarter-brick and eighth-brick isolated converters up to 600 W.
Empfohlen
Server / Data-Center Power Supply Unit
The UCC28950 suits server and data-center PSU designs because the integrated synchronous rectifier control removes one external SR controller from the BOM. According to the TI datasheet, the controller supports adaptive ZVS across the full load range, enabling >94% efficiency required by 80 PLUS Titanium and ENERGY STAR data-center standards. The 1 MHz programmable switching frequency allows a smaller magnetic footprint, increasing power density in CRPS and Open Compute power shelves. Pair it with a TI PFC controller upstream for a complete high-efficiency AC/DC solution.
Empfohlen
Industrial Battery Charger (24 V / 48 V)
The UCC28950 supports isolated industrial battery chargers because it provides peak current-mode control with programmable soft start, which prevents inrush stress on the battery. According to TI E2E forum feedback, designers use this controller to deliver 1 to 2 kW of isolated power with synchronous rectification for >93% efficiency. The wide input range supports universal rectified AC input downstream of a PFC stage. Programmable cycle-by-cycle current limiting protects against battery short-circuit events during charge cycles.
Empfohlen
Renewable-Energy Solar Inverter DC/DC Stage
The UCC28950 is widely deployed in solar inverter DC/DC boost/isolation stages because the peak current-mode control accepts a wide string input range from 24 V to 80 V open-circuit panels without instability. According to TI application notes, the integrated synchronous rectification delivers the chain efficiency gains required to maximize energy harvest under varying irradiance. The -40 C to +125 C operating range covers outdoor inverter environments including rooftop and ground-mount systems. Burst-mode operation at light load improves morning and evening efficiency to meet grid-tie certification.
Empfohlen
High-Power-Density Point-of-Load Front End
The UCC28950 enables high-density intermediate bus converters feeding downstream POL regulators in networking and FPGA platforms. According to the TI datasheet, the programmable switching frequency up to 1 MHz allows designers to push switching frequency without sacrificing ZVS, dramatically shrinking magnetics. For 48 V to 12 V or 48 V to 5 V buses, the controller maintains high efficiency across load, reducing cooling complexity. The integrated SR control eliminates external timing components and reduces overall BOM cost in space-constrained systems.
Empfohlen
Electric Vehicle Auxiliary Isolated DC/DC
The UCC28950 -Q1 automotive variant supports 12 V auxiliary battery DC/DC converters in xEV powertrains because the AEC-Q100 qualification covers automotive reliability requirements. According to TI automotive documentation, the controller handles the high-voltage battery bus downconverted to 12 V for body-electronics loads. The integrated synchronous rectification delivers high efficiency to reduce heat dissipation in tightly sealed automotive electronics bays. Designers pair it with TI automotive-grade gate drivers for the primary full-bridge FETs.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für UCC28950 – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | UCC28951PW | UCC28950QPWRQ1 | UCC28951QPWRQ1 | UCC28950PWR | UCC28951PWR |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 24-pin TSSOP (PW) | 24-pin TSSOP (PW) - same | 24-pin TSSOP (PWR) - same | 24-pin TSSOP (PWR) - same | 24-pin TSSOP (PWR) - same | 24-pin TSSOP (PWR) - same |
| Switching Frequency (max) | 1 MHz | 1 MHz | 1 MHz | 1 MHz | 1 MHz | 1 MHz |
| Adaptive ZVS | Yes | Yes (improved) | Yes | Yes (improved) | Yes | Yes (improved) |
| Light-Load Efficiency | Standard | Improved | Standard | Improved | Standard | Improved |
| Automotive Qualified | No | No | Yes (AEC-Q100) | Yes (AEC-Q100) | No | No |
| Synchronous Rectifier Control | Yes | Yes | Yes | Yes | Yes | Yes |
| Peak Current-Mode Control | Yes | Yes | Yes | Yes | Yes | Yes |
Wichtigste Unterscheidungsmerkmale
- Integrated synchronous-rectifier control removes external SR controller (vs. UCC3895)
- Adaptive ZVS across the full load range (vs. LM5046)
- Direct drop-in replacement path with UCC28951 (vs. UCC3895)
Designhinweise
Estimated layout recommendation based on standard phase-shifted controller practice: place the timing capacitor (CT), oscillator resistor (RT), and soft-start capacitor (CSS) adjacent to their respective pins with minimal trace length. Keep the CS current-sense trace short and routed away from switching nodes to avoid noise coupling. A solid power ground (PGND) island connected to analog ground (GND) at a single point reduces ground loops. High-side bootstrap capacitors (VB) must be placed close to their OUTx pins to supply peak gate charge.
Estimated thermal calculation: at VIN=48 V, VOUT=12 V, IOUT=20 A and 92% efficiency, the full-bridge converter dissipates roughly 50 W in the primary FETs, the SR FETs, and the transformer. The TSSOP-24 package alone (theta_JA approximately 80-90 C/W on a 4-layer JEDEC board) needs significant copper pour or external airflow for full-power operation. For higher-power designs above 600 W, consider assigning a copper plane of at least 1 sq inch to the thermal pad and surrounding circuitry under continuous operation.
Do not skip the dedicated SYNC resistor on multi-controller systems where multiple UCC28950 devices must be synchronized - TI application note SLUA609 specifies the master/slave configuration for interleaving three or more controllers. Ensure the VCC hold-up capacitance sustains operation through the CV/CC threshold of the source supply. Reversing CS polarity or omitting the RC filter on the current-sense input destabilizes the peak current-mode loop and can cause subharmonic oscillation at duty cycles above 50 percent.
Compliance-Informationen
Standard UCC28950 is industrial grade - use UCC28950QPWRQ1 for AEC-Q100 automotive applications. RoHS and lead-free compliant per TI product page.
