RTQ2811A - 17V/20A ACOT Buck Converter for Server POL | Richtek
MPN: RTQ2811A ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.2 | $3.20 |
| 10 | $2.88 | $28.80 |
| 100 | $2.55 | $255.00 |
| 500 | $2.21 | $1,105.00 |
| 1,000 | $1.92 | $1,920.00 |
RTQ2811A Overview
A DC/DC buck converter (step-down switching regulator) is a type of switched-mode power supply (SMPS) that uses high-side and low-side MOSFET switches plus an LC output filter to convert a higher DC input voltage into a lower, regulated DC output voltage. Within the power management hierarchy, a buck converter sits under DC-DC converters, which sit under voltage regulators, which sit under power management ICs (PMICs), which sit under integrated circuits. The ACOT topology used in the RTQ2811A is a fast-transient variant of the constant on-time control family that minimizes output capacitance while maintaining tight DC regulation.
Key differentiating features include ACOT control for sub-microsecond transient response, integrated high-side and low-side MOSFETs supporting up to 20A continuous output current, programmable switching frequency, internal compensation, and integrated protection features including OCP, OVP, UVP, and thermal shutdown. The exposed-pad QFN package keeps thermal resistance low for sustained high-current operation in confined server environments. According to the manufacturer application note AN094, the RTQ2811A is specifically designed for next-generation AI server SSDs and POL power modules.
Typical applications include server/datacenter SSD power, AI accelerator cards, point-of-load modules for ASICs, FPGA core rails, networking switch ASICs, and high-current PoL converters for telecom boards. When designing, prioritize input capacitor placement adjacent to the high-side MOSFET return path and use a sufficient copper pour on the exposed pad to keep junction rise within safe limits at 20A load.
Drop-in alternatives for RTQ2811A — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
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Request AlternativesRTQ2811A Maximum Ratings & Electrical Characteristics
| Topology | Synchronous Step-Down (ACOT) |
| Maximum Output Current | 20 A |
| Maximum Input Voltage | 17 V |
| Switching Frequency | Programmable |
| Control Architecture | ACOT (Adaptive Constant On-Time) |
| MOSFETs | Integrated high-side and low-side |
| Operating Temperature | -40C to +125C |
| Over-Current Protection | Yes |
| Over-Voltage Protection | Yes |
| Under-Voltage Protection | Yes |
| Thermal Shutdown | Yes |
| Internal Compensation | Yes |
| Mounting Type | Surface Mount |
RTQ2811A standard Pin Configuration Guide
Pin configuration for RTQ2811A (standard package). This power device features gate, drain, and source terminals. For non-polarized packages, refer to the manufacturer datasheet for exact pin 1 orientation and footprint details. Common applications include power supply design, motor driving, and load switching.
No detailed pinout data available for RTQ2811A.
Refer to the datasheet for full pin configuration.
Typical Applications
RTQ2811A is suitable for 6 applications: Data Center Server SSD Power, AI Accelerator Card Point-of-Load, Telecom Board POL Modules, Networking Switch ASIC Power, FPGA Core Rail Supply, Industrial Server Motherboard VR.
Data Center Server SSD Power
The RTQ2811A's 20A output current and ACOT control architecture make it well-suited to power next-generation enterprise SSDs in hyperscale data centers. Server SSDs require sub-microsecond transient response during heavy read/write workloads; the ACOT topology minimizes output capacitance while maintaining tight regulation. Per Richtek AN094, the device is specifically designed for this use case, integrating high efficiency, intelligent monitoring, programmable control, and flexible architecture options to deliver stable power in high-density, high-transient-load environments.
Recommended
AI Accelerator Card Point-of-Load
The RTQ2811A 20A buck converter supplies sub-1V core rails to AI accelerator ASICs that demand fast load-step response. The ACOT control topology delivers sub-microsecond transient recovery, critical when an AI workload transitions between idle inference and sustained matrix multiplication. Integrated high-side and low-side MOSFETs in an exposed-pad QFN package allow compact PCB placement near the ASIC, minimizing parasitic inductance on the critical output loop.
Recommended
Telecom Board POL Modules
The RTQ2811A supports telecom board point-of-load modules that need 20A from a 12V bus with high efficiency. ACOT control maintains regulation across the wide load range typical of base-station digital signal processing. The 17V maximum input voltage provides sufficient headroom for transient telecom bus events. Integrated OCP/OVP/UVP/OTP protections simplify system-level safety certification for carrier-grade equipment.
Recommended
Networking Switch ASIC Power
The RTQ2811A powers high-performance switch ASICs that step down from a 12V intermediate bus. ACOT control handles fast load steps during packet-processing bursts without requiring excessive output bulk capacitance. The exposed-pad QFN package keeps thermal resistance low, which is important in the constrained airflow of dense switch chassis. Programmable switching frequency allows tuning for EMI compliance with nearby SerDes lanes.
Recommended
FPGA Core Rail Supply
The RTQ2811A provides the sub-1V core rail for mid-range FPGAs that draw up to 20A under peak DSP utilization. ACOT control responds to sub-microsecond load steps characteristic of FPGA fabric switching, reducing required decoupling and shrinking PCB area. Internal compensation eliminates external RC networks and reduces design iterations during FPGA bring-up. Verify the FPGA's input voltage tolerance and load step amplitude against the RTQ2811A transient specification.
Recommended
Industrial Server Motherboard VR
The RTQ2811A serves as a high-density voltage regulator on industrial server motherboards where space and thermal headroom are constrained. Integrated MOSFETs and ACOT control minimize external component count, freeing PCB real estate for memory or expansion slots. OCP, OVP, UVP, and OTP protections meet industrial server reliability targets. Industrial temperature grade supports deployment in non-datacenter environments such as factory automation and edge compute.
Recommended
Recommended Products Summary
Engineering reference data for RTQ2811A — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | RTQ2820A | TPS54331DR |
|---|---|---|---|
| Brand | Richtek | Richtek | Texas Instruments |
| Maximum Output Current | 20 A | 20 A | 3 A |
| Maximum Input Voltage | 17 V | 17 V | 28 V |
| Control Architecture | ACOT | ACOT | Current-mode PWM (Eco-Mode) |
| Integrated MOSFETs | Yes (HS + LS) | Yes (HS + LS) | Yes (HS + LS) |
| Switching Frequency | Programmable | Programmable | Up to ~600 kHz |
| Target Application | Server SSD / AI POL | General-purpose POL | Industrial / distributed POL |
Key Differentiators
- ACOT control for sub-microsecond transient response (vs TPS54331DR)
- 20A output in compact exposed-pad QFN (vs TPS54331DR)
- Designed for AI server SSD POL applications (vs RTQ2820A)
Design Notes
Estimated: at VIN=12V, VOUT=1.0V, and 20A load, the RTQ2811A dissipates approximately (12 - 1.0) x 20 = 220W if hard-switching, but practical efficiency is ~90%, so dissipation is closer to 22W. The exposed-pad QFN package requires substantial copper pour on inner and outer layers to keep junction temperature rise within safe operating area. Designers must consult the manufacturer thermal model for layout-specific theta_JA before finalizing the PCB stack-up.
Place input ceramic capacitors adjacent to the high-side MOSFET return path to minimize switching noise. Use a 4-layer PCB with dedicated power and ground planes; route the output inductor and capacitor loop as small as possible. The exposed pad must be soldered to a continuous ground plane with thermal vias to inner layers for heat extraction. Avoid routing sensitive analog feedback traces near the switching node.
Do not exceed 17V at the input; transients above this rating can damage the internal MOSFETs. Ensure feedback resistor values use 1% tolerance or better to maintain output voltage accuracy. The bootstrap capacitor value and diode selection are critical for proper high-side drive; do not substitute with arbitrary components. Verify the RTQ2811A's load-step transient specification against your application's worst-case load step amplitude.
Compliance Information
Compliance status not provided in verified web data. Richtek product selection guide (Jan 2024) lists company-wide compliance but specific RTQ2811A datasheet must be consulted for part-level certification.
