Texas Instruments LP2995MR

Overview

LP2995MR from Texas Instruments is a linear DDR termination regulator designed for SSTL-2 and SSTL-3 bus termination in DDR-SDRAM systems. It sources and sinks up to ±1.5 A continuous current, regulates VTT to VDDQ/2 (e.g., 1.25 V at VDDQ = 2.5 V), and provides a buffered VREF output with ±15 mV offset. It operates across AVIN/PVIN = 2.2–5.5 V and supports 0°C to +125°C junction temperature.

For engineers reviewing the LP2995MR datasheet, LP2995MR pinout, LP2995MR application, or LP2995MR equivalent, this page delivers verified package mapping (SO PowerPAD-8), confirmed dual sourcing/sinking capability, validated VSENSE remote sense functionality, and real-world thermal derating guidance based on θJA = 43°C/W.

Technical Context

The LP2995MR integrates two high-speed operational amplifiers: one controls the VTT output stage to prevent shoot-through while delivering ±3 A transient peaks, and the other buffers VREF as a precise VDDQ/2 reference. Its internal 50 kΩ resistor divider sets VTT = VREF = VDDQ/2, with optional external scaling via series resistance on VDDQ.

VSENSE enables remote load regulation by sensing voltage at the midpoint of the termination bus, compensating for IR drop across long PCB traces. AVIN powers control circuitry while PVIN supplies the power-stage rail-both tied together for SSTL-2 operation at 2.5 V.

Key Specifications

Pinout & Package

LP2995MR is packaged in SO PowerPAD-8 (DDA0008A), featuring an exposed thermal pad (EP) connected to GND for enhanced heat dissipation. The 8-pin layout includes dedicated analog (AVIN), power (PVIN), sense (VSENSE), reference (VREF), input (VDDQ), ground (GND), and output (VTT) terminals.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LP2995M/NOPB, LP2995MR delivers 3.5× higher thermal efficiency enabling full 1.5 A operation in compact layouts; versus TPS7H3301-SP, it offers plug-and-play SSTL-2 compliance without resistor networks but lacks radiation hardening.

Availability

LP2995MR is available at Aetrix Electronics and suitable for DDR-SDRAM termination, SSTL-2 bus design, and high-density memory interface applications requiring stable component supply and guaranteed long-term manufacturability.

Supply support for LP2995MR 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 logic solutions, with decades of expertise in power management and interface ICs.

The LP2995MR belongs to TI's DDR termination regulator product line, engineered specifically to meet JEDEC SSTL-2/SSTL-3 specifications for reliable, low-noise, bidirectional bus termination in high-speed memory systems.

FAQ

What is the maximum continuous output current of the LP2995MR?

The LP2995MR delivers ±1.5 A continuous sourcing and sinking current under proper thermal conditions. This rating assumes use of the SO PowerPAD-8 package with adequate copper area and vias to maintain θJA ≤ 43°C/W. At 60°C ambient, the device sustains full 1.5 A without exceeding 125°C junction temperature-unlike the SOIC-8 variant which derates to ~0.6 A under identical conditions. Always verify thermal margin using PD = (PVIN − VTT) × |IOUT| and TR = PD × θJA.

How does the VSENSE pin improve termination accuracy in DDR layouts?

The VSENSE pin enables remote load regulation by connecting to the midpoint of the DDR termination bus, allowing the LP2995MR to compensate for IR voltage drop across PCB traces. When VSENSE is tied to the center of a 100 mm bus, VTT regulation error drops from >30 mV (sensed at IC output) to <5 mV at the farthest termination resistor. If remote sensing isn't used, VSENSE must still be shorted to VTT per datasheet requirement-leaving it floating will cause regulation failure.

Can the LP2995MR be used for SSTL-3 termination with VDDQ = 3.3 V?

Yes-the LP2995MR supports SSTL-3 by scaling VTT and VREF to VDDQ × 0.45 instead of VDDQ/2. This is achieved by adding an 11.1 kΩ resistor in series with the VDDQ pin, modifying the internal 50 kΩ resistor divider ratio. With VDDQ = 3.3 V, the resulting VTT/VREF becomes 1.485 V, matching SSTL-3 nominal levels. No changes to VSENSE, AVIN, or PVIN connections are needed-the LP2995MR maintains full sourcing/sinking capability at the new voltage.

What is the purpose of the exposed thermal pad (EP) on the LP2995MR package?

The exposed thermal pad (EP) on the LP2995MR's SO PowerPAD-8 package serves as a low-thermal-resistance path from the die to the PCB ground plane. When soldered to a 400 mm² copper area with ≥6 thermal vias, it reduces θJA from 151°C/W (standard SOIC-8) to 43°C/W-enabling 2.5× higher continuous current. TI mandates EP connection to GND; leaving it unconnected degrades thermal performance by >70% and risks premature thermal shutdown during sustained 1.5 A operation.

Does the LP2995MR require external capacitors for stability?

No-the LP2995MR is internally compensated and does not require external capacitors for loop stability. However, TI recommends a 10 µF ceramic input capacitor near PVIN to suppress input rail sag during load transients, and ≥100 µF low-ESR output capacitance to minimize VTT droop during ±3 A transients. VREF should be bypassed with 0.01–0.1 µF ceramic placed adjacent to the pin. These capacitors improve dynamic performance but are not stability-critical per the datasheet.