My Inquiry
My Account
Analog Devices Inc. LTC3876EUHF#TRPBF
- Part No.:
- LTC3876EUHF#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- Special Purpose Regulators
- Package:
- 38-WFQFN Exposed Pad
- Datasheet:
-
LTC3876EUHF#TRPBF.pdf
- Description:
- IC REG CTRLR DDR 2OUT 38QFN
- Quantity:
- Payment:
- Shipping:
Inventory:1,461
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3876EUHF#TRPBF from Analog Devices (formerly Linear Technology) is a dual-channel synchronous DC/DC controller IC designed specifically for DDR memory power delivery, integrating VDDQ and VTT regulation with differential sensing and a precision ±50mA linear VTTR reference. It supports DDR1–DDR3 standards, operates from 4.5V to 38V input, delivers 1.0V–2.5V VDDQ and 0.5V–1.25V VTT/VTTR outputs, and achieves ±0.67% VDDQ accuracy and ±1.2% VTTR regulation over temperature.
For engineers reviewing the LTC3876EUHF#TRPBF datasheet, LTC3876EUHF#TRPBF pinout, LTC3876EUHF#TRPBF application, or LTC3876EUHF#TRPBF equivalent, key selection considerations include differential VDDQ sensing architecture, dual-channel valley current mode control with programmable 200kHz–2MHz switching, ±50mA VTTR load capability, thermal performance in 5mm × 7mm QFN, and DDR-specific features including VTT tracking, PGOOD monitoring, and load transient suppression via DTR1.
Technical Context
The LTC3876EUHF#TRPBF implements two independent valley current-mode controllers: Channel 1 regulates VDDQ using differential feedback (VOUTSENSE1+ / VOUTSENSE1–) referenced to a precise 0.6V internal bandgap, while Channel 2 controls VTT by tracking the VTTR reference with <20mV total DC error. Both channels support RSENSE or DCR current sensing, programmable frequency via RT resistor, and phase control via PHASMD pin.
Its analog subsystem includes dedicated error amplifiers (ITH1/ITH2), precision differential sense amplifiers, a Kelvin-connected VTTR reference buffered from VDDQSNS–VOUTSENSE1–, and integrated gate drivers with 2.5Ω TG pull-up and 0.8Ω BG pull-down on-resistance. The device enables forced continuous or discontinuous mode operation per channel and supports external clock synchronization via MODE/PLLIN with configurable CLKOUT phase alignment.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4.5V to 38V - supports wide-range industrial and server power rails without pre-regulation. |
| VDDQ Output Range | 1.0V to 2.5V - covers DDR1 (2.5V), DDR2 (1.8V), DDR3 (1.5V), and LPDDR variants. |
| VTT/VTTR Output Range | 0.5V to 1.25V - tracks one-half VDDQ with ±1.2% accuracy across ±50mA load and temperature. |
| Switching Frequency | 200kHz to 2MHz - programmable via RT pin; enables optimization of efficiency vs. size for high-current DDR applications. |
| VDDQ Voltage Accuracy | ±0.67% - guaranteed differential regulation ensures tight DDR termination compliance under line/load/temperature variation. |
| Min On/Off Time | tON(MIN) = 30ns, tOFF(MIN) = 90ns - supports high VIN-to-low VOUT conversion at high frequencies with stable light-load operation. |
| Package | 38-pin 5mm × 7mm QFN (UHF) - thermally enhanced with exposed PGND pad (Pin 39) for low θJA = 34°C/W. |
Pinout & Package
38-pin plastic QFN package (UHF), 5mm × 7mm body, 0.5mm pitch, exposed thermal pad (Pin 39) soldered to PCB PGND. Pin numbering follows top-view standard with Pin 1 at top-left corner.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| ITH2 (Pin 1) | VTT Current Control Threshold | Error amplifier output for Channel 2; sets valley current limit with zero-sense at 1.2V; supports symmetric ± current sensing. |
| VDDQSNS (Pin 2) | VDDQ Sense Reference Input | Positive input to internal 210kΩ VTT reference divider; connects to VDDQ feedback network to establish VTTR = 0.5×(VDDQSNS – VOUTSENSE1–). |
| VTTR (Pin 3) | VTT Linear Reference Output | Buffered, Kelvin-sensed 0.5×VDDQ reference; specified for ±50mA load with 1.2% accuracy; directly drives DDR VREF pin. |
| VTTRVCC (Pin 4) | VTTR Reference Supply | Power input for VTTR buffer; requires RC decoupling (2.2μF + 1Ω) from DRVCC to suppress noise coupling into reference path. |
| MODE/PLLIN (Pin 5) | Mode Selection / Clock Sync Input | Selects forced continuous/discontinuous mode or accepts external clock (100kHz–2.6MHz) for synchronization of both channels. |
| CLKOUT (Pin 6) | Programmable Clock Output | Open-drain output swinging between INTVCC and SGND; phase relative to SW1 is set by PHASMD pin (0°/60°/90°/120°/180°/240°). |
| SGND (Pin 7) | Signal Ground Reference | Analog ground for all small-signal pins; must be connected to exposed pad and PGND via single low-inductance trace to minimize noise. |
| RT (Pin 8) | Frequency Programming Input | Resistor-to-SGND sets switching frequency (200kHz–2MHz); floating defaults to ~190kHz; enables precise timing control without external oscillator. |
Key Features
| Feature | Design Value |
|---|---|
| Dual DDR Power Controllers | Independent VDDQ (Channel 1) and VTT (Channel 2) regulation with synchronized or phase-shifted operation for optimal thermal distribution in high-density memory modules. |
| Differential VDDQ Sensing | VOUTSENSE1+/VOUTSENSE1– inputs enable remote sensing across PCB traces and connectors, eliminating IR drop errors and ensuring accurate voltage at DDR IC pins. |
| ±50mA VTTR Linear Reference | VTTR output maintains 1.2% regulation accuracy over full ±50mA load range and –40°C to 125°C, meeting DDR3/DDR4 VREF stability requirements without external op-amps. |
| Valley Current Mode Control | Control architecture provides inherent cycle-by-cycle current limiting, fast transient response, and stable operation with ceramic output capacitors and low-ESR designs. |
| Load Transient Suppression (DTR1) | DTR1 pin detects rapid load release and forces BG off to accelerate inductor current decay, reducing VDDQ overshoot during memory read-to-idle transitions. |
Applications
| Motherboard Memory Power | Servers & Data Center Memory Modules |
|---|---|
Use Scenario: Providing regulated 1.5V VDDQ and 0.75V VTT to DDR3 DIMMs on x86 server motherboards with 4.5V–14V input rail. IC Role / Device Role / Timing Role: Dual-channel controller managing both memory core supply and termination voltage with differential sensing and tracking reference. Use Value: Enables single-chip DDR3 compliance with ±0.67% VDDQ accuracy and <20mV VTT tracking error, reducing BOM count and layout complexity versus discrete solutions. | Use Scenario: High-current DDR4 memory subsystems in 1U rack servers requiring 20A VDDQ and ±10A VTT sourcing/sinking capability. IC Role / Device Role / Timing Role: Primary power controller delivering tightly tracked VDDQ/VTT with programmable 2MHz switching and thermal-aware phase control. Use Value: Supports forced continuous mode for low-noise operation and phase shifting (via PHASMD) to distribute heat across multiple phases, improving system thermal margin. |
| Industrial Embedded Memory Systems | Networking Equipment Memory Interfaces |
Use Scenario: DDR2-powered FPGA-based industrial controllers operating from wide-input 9V–36V DC supplies in harsh environments. IC Role / Device Role / Timing Role: Robust DDR power manager with 4.5V–38V input tolerance, –40°C to 125°C operation, and integrated overvoltage/current protection. Use Value: Eliminates need for external UVLO/OVP circuitry; built-in PGOOD, foldback current limiting, and thermal shutdown ensure reliable field operation. | Use Scenario: Line-card memory interfaces in telecom switches requiring synchronized multi-controller timing and low EMI. IC Role / Device Role / Timing Role: Clock generator and synchronizer via CLKOUT/MODE/PLLIN, enabling deterministic phase alignment across multiple LTC3876 units. Use Value: Reduces system-level jitter and improves signal integrity by eliminating asynchronous switching noise between adjacent memory power domains. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-channel DDR power controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ISL6522CRZ-T | Single-channel DDR controller with external VTT LDO; no integrated VTTR reference or differential VDDQ sensing. | Lacks dual-channel integration and ±50mA VTTR capability; requires additional components for full DDR3 compliance. | Choose when cost sensitivity outweighs integration benefits and board space allows discrete VTT implementation. |
| TPS51220ARUKT | Integrated MOSFET drivers with lower current rating (12A max); no VTTR reference; uses single-ended sensing only. | Not suitable for high-current DDR3/DDR4 systems requiring >15A VDDQ or precision VTT tracking. | Select for compact notebook memory power where 12A VDDQ and basic VTT buffering suffice. |
Compared with ISL6522CRZ-T and TPS51220ARUKT, the LTC3876EUHF#TRPBF delivers higher integration (dual controllers + VTTR reference), superior accuracy (±0.67% VDDQ), and robust differential sensing-making it optimal for high-reliability, high-current DDR3/DDR4 server and industrial applications where component count and regulation fidelity are critical.
Availability
LTC3876EUHF#TRPBF is available at Aetrix Electronics and suitable for motherboard memory power, server DDR modules, industrial embedded systems, and networking equipment requiring stable component supply and long-term lifecycle support.
Supply support for LTC3876EUHF#TRPBF 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
Analog Devices, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors.
The LTC3876EUHF#TRPBF belongs to Linear's Power Management product line, engineered specifically for high-efficiency, high-accuracy DDR memory power delivery in demanding computing and infrastructure applications.
FAQ
What is the maximum supported input voltage for the LTC3876EUHF#TRPBF?
The LTC3876EUHF#TRPBF supports an absolute maximum input voltage of 40V on the VIN pin, with a recommended operating range of 4.5V to 38V. This wide input range allows direct connection to unregulated 5V, 12V, or 24V system rails without intermediate regulation, simplifying power architecture in servers and industrial systems where input voltage may vary significantly under load or during transients.
How does the LTC3876EUHF#TRPBF achieve ±0.67% VDDQ output voltage accuracy?
The LTC3876EUHF#TRPBF achieves ±0.67% VDDQ accuracy through a combination of differential sensing (VOUTSENSE1+ and VOUTSENSE1–), a precision 0.6V internal bandgap reference, and trimming of the error amplifier transconductance (gm(EA) = 1.7mS). The differential architecture rejects common-mode noise and PCB IR drop, while production testing across line, load, and temperature ensures the combined specification remains within ±0.67% under real-world conditions defined in the datasheet's combined regulation test.
Can the LTC3876EUHF#TRPBF be used for DDR4 memory power applications?
Yes, the LTC3876EUHF#TRPBF supports DDR4 memory power requirements through its programmable VDDQ range (1.0V–2.5V), which covers DDR4's nominal 1.2V supply, and its ±50mA VTTR reference capable of driving DDR4 VREF loads. While originally characterized for DDR1–DDR3, its electrical specifications-including 200kHz–2MHz switching, differential sensing, and tight tracking-meet DDR4's dynamic regulation and noise immunity demands when implemented with appropriate external components per the application circuit guidelines.
What is the function of the DTR1 pin on the LTC3876EUHF#TRPBF?
The DTR1 pin on the LTC3876EUHF#TRPBF detects rapid load current reduction (e.g., DDR memory transitioning from active read to idle state) and triggers immediate bottom gate (BG) turn-off to accelerate inductor current decay. This action minimizes VDDQ output voltage overshoot during load-release transients-a critical requirement for DDR signal integrity. When not needed, DTR1 can be disabled by tying it to INTVCC.
Does the LTC3876EUHF#TRPBF support external clock synchronization?
Yes, the LTC3876EUHF#TRPBF supports external clock synchronization via the MODE/PLLIN pin. When an external clock signal (100kHz–2.6MHz, CMOS-compatible) is applied, both VDDQ and VTT channels operate in forced continuous mode and lock to the input frequency with phase alignment controlled by the PHASMD pin. This feature enables deterministic timing across multiple LTC3876EUHF#TRPBF devices in multi-phase or multi-rank memory systems, reducing beat-frequency noise and improving EMI performance.
LTC3876EUHF#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 38-WFQFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Applications:
- Controller, DDR
- Voltage - Input:
- 4.5V ~ 38V
- Number of Outputs:
- 2
- Voltage - Output:
- Adjustable
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 38-QFN (5x7)
LTC3876EUHF#TRPBF FAQ
1.How can I place an order for LTC3876EUHF#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3876EUHF#TRPBF on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LTC3876EUHF#TRPBF reliable?
The price and inventory of LTC3876EUHF#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3876EUHF#TRPBF is usually 5 days.
3.What payment methods are accepted for LTC3876EUHF#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3876EUHF#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3876EUHF#TRPBF?
LTC3876EUHF#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3876EUHF#TRPBF order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LTC3876EUHF#TRPBF?
For technical support, including LTC3876EUHF#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3876EUHF#TRPBF requirements.
6.How does Aetrix verify that LTC3876EUHF#TRPBF is sourced from the original manufacturer or authorized distributors?
All LTC3876EUHF#TRPBF products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LTC3876EUHF#TRPBF meets industry standards.
7.What is the process for return or replacement of LTC3876EUHF#TRPBF?
All LTC3876EUHF#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3876EUHF#TRPBF, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LTC3876EUHF#TRPBF part is unused and in its original packaging.
Return procedure for LTC3876EUHF#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3876EUHF#TRPBF Tags
-
TPS51206DSQR
Texas Instruments
-
TPS51200DRCR
Texas Instruments
-
TPS51200DRCT
Texas Instruments
-
TPS62740DSSR
Texas Instruments
-
TPS51100DGQR
Texas Instruments
-
NCP51200MNTXG
onsemi
-
NCP51400MNTXG
onsemi
-
RT9026GSP
Richtek USA Inc.
-
LP2998MRX/NOPB
Texas Instruments
-
TPS51200QDRCRQ1
Texas Instruments
-
DPA423GN-TL
Power Integrations
-
LM10011SD/NOPB
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
