Texas Instruments TPS51100DGQRG4

Overview

TPS51100DGQRG4 from Texas Instruments is a 3-A sink/source DDR termination regulator with integrated VTTREF buffered reference output, designed for DDR, DDR2, and DDR3 memory bus termination. It operates from 4.75 V to 5.25 V VIN and supports VLDOIN from 1.2 V to 3.6 V, delivers ±20 mV accuracy on both VTT and VTTREF, and maintains fast transient response using only 20 µF ceramic output capacitance (2 × 10 µF). It is used in notebook PCs and space-constrained embedded systems requiring JEDEC-compliant VTT regulation.

For engineers reviewing the TPS51100DGQRG4 datasheet, TPS51100DGQRG4 pinout, TPS51100DGQRG4 application, or TPS51100DGQRG4 equivalent, key selection criteria include its dual-state S3/S5 sleep control, remote sensing (VTTSNS), droop compensation, ±40 mV load regulation over ±3 A, and thermal shutdown at 160°C - all critical for DDR power integrity in low-power, high-density memory subsystems.

Technical Context

The TPS51100DGQRG4 implements a tracking linear regulator architecture where VTT dynamically follows half of VDDQSNS via an integrated divider, LPF, and buffer to generate VTTREF. Its feedback loop employs remote sensing (VTTSNS) to reject PCB trace resistance effects and maintain tight regulation under fast load transients up to ±3 A.

It features dual independent sleep-state controls: S3 input places VTT in high-impedance while retaining VTTREF, and S5 input discharges both VTT and VTTREF to ground during soft-off. UVLO on VIN (3.4–4.0 V threshold) and thermal shutdown (160°C, 10°C hysteresis) provide non-latching protection without external circuitry.

Key Specifications

Pinout & Package

The TPS51100DGQRG4 is housed in a thermally enhanced 10-pin HVSSOP PowerPAD™ package (3.00 mm × 3.00 mm body, 4.98 mm × 3.05 mm footprint) with exposed die pad for PCB-level thermal dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DDR termination regulator applications.

Compared with TPS51100DGQRG4, the TPS51116RGER offers higher efficiency but adds complexity and board area, while the ISL6521CRZ-T lacks integrated VTTREF and S5 control - making TPS51100DGQRG4 the optimal choice for new DDR2/DDR3 designs prioritizing integration, JEDEC compliance, and minimal external components.

Availability

TPS51100DGQRG4 is available at Aetrix Electronics and suitable for DDR memory termination, SSTL-18 bus regulation, and HSTL level translation requiring stable component supply, JEDEC compliance, and thermal reliability in space-constrained embedded systems.

Supply support for TPS51100DGQRG4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with decades of expertise in memory interface power solutions.

The TPS51100DGQRG4 belongs to TI's DDR termination regulator product line, engineered specifically for JEDEC-compliant VTT and VTTREF generation in notebook, server, and industrial memory subsystems where space, thermal performance, and sleep-state fidelity are critical.

FAQ

What is the primary function of the TPS51100DGQRG4 in a DDR memory system?

The TPS51100DGQRG4 serves as a 3-A sink/source termination regulator that generates precise VTT and VTTREF voltages for DDR, DDR2, and DDR3 memory buses. It tracks half of VDDQSNS to produce VTTREF, then regulates VTT to match it with ±20 mV accuracy. Its integrated S3/S5 control enables JEDEC-compliant suspend states, and remote VTTSNS sensing ensures regulation accuracy at the memory module - all within a compact 10-pin HVSSOP package.

How does the TPS51100DGQRG4 achieve fast transient response with only 20 µF of output capacitance?

The TPS51100DGQRG4 achieves fast transient response through an optimized feedback loop with droop compensation and remote sensing (VTTSNS). By connecting VTTSNS directly to the positive terminal of the VTT output capacitor(s), the device rejects PCB trace resistance, allowing the control loop to respond to load steps up to ±3 A while maintaining ±40 mV regulation. This eliminates the need for large bulk capacitance or external compensation networks.

What are the voltage requirements for VLDOIN and how does it affect TPS51100DGQRG4 operation?

VLDOIN must be supplied between 1.2 V and 3.6 V and serves as the power source for both the VTT LDO and VTTREF output stage. When VLDOIN equals VDDQSNS (e.g., 1.5 V for DDR3), VTT is regulated to 0.75 V; when VLDOIN is 1.8 V (DDR2), VTT is 0.9 V. Lower VLDOIN reduces power dissipation during VTT sourcing, making it critical for thermal design - especially in high-current or high-ambient-temperature environments.

Can the TPS51100DGQRG4 be used for DDR4 memory termination?

No, the TPS51100DGQRG4 is not specified for DDR4. It supports DDR, DDR2, and DDR3 per JEDEC standards, with VTTREF derived as exactly 0.5 × VDDQSNS - matching DDR3's 0.75-V VTT (at 1.5-V VDDQ) and DDR2's 0.9-V VTT (at 1.8-V VDDQ). DDR4 requires 0.675-V VTT referenced to 1.35-V VDDQ, which falls outside the device's supported VLDOIN and tracking range; TI's TPS51200 or TPS51216 are recommended for DDR4.

What thermal design practices are required to ensure reliable operation of the TPS51100DGQRG4?

To ensure reliable operation, the TPS51100DGQRG4's exposed PowerPAD must be soldered to a dedicated thermal land (minimum 3 mm × 3 mm) connected via ≥4 vias (0.33 mm diameter) to an internal ground plane. Layout must isolate PGND from signal GND, route VTTSNS separately from high-current VTT traces, and place input/output capacitors as close as possible to their respective pins. With this implementation, junction-to-board thermal resistance drops to 45.4°C/W, enabling continuous ±3-A operation at 85°C ambient.