My Inquiry
My Account
Texas Instruments LP38853SX-ADJ/NOPB
- Part No.:
- LP38853SX-ADJ/NOPB
- Manufacturer:
- Texas Instruments
- Package:
- TO-263-8, D2PAK (7 Leads + Tab), TO-263CA
- Datasheet:
-
LP38853SX-ADJ/NOPB.pdf
- Description:
- IC REG LIN POS ADJ 3A DDPAK
- Quantity:
- Payment:
- Shipping:
Inventory:401
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LP38853SX-ADJ/NOPB from Texas Instruments is a 3-A, fast-response adjustable LDO linear regulator with dual-input bias architecture (VIN/VBIAS), ±2% output voltage accuracy across –40°C to +125°C, 240 mV typical dropout at full load, and integrated soft-start/enable functions - used in FPGA core power, server I/O rails, and SMPS post-regulation.
For engineers reviewing the LP38853SX-ADJ/NOPB datasheet, LP38853SX-ADJ/NOPB pinout, LP38853SX-ADJ/NOPB application, or LP38853SX-ADJ/NOPB equivalent, key selection considerations include VBIAS-dependent operating range (3–5.5 V), ADJ-pin feedback topology, thermal derating for DDPAK/TO-263 package, and soft-start capacitor timing dependency on rSS = 13.5 kΩ.
Technical Context
The LP38853SX-ADJ/NOPB uses an NMOS pass transistor driven by a separate VBIAS rail, enabling ultra-low VIN operation while maintaining high bandwidth and stability with only 10-µF ceramic output capacitance. Its CMOS control circuitry delivers low quiescent current (7–9 mA from VIN, 3–4.5 mA from VBIAS) across 0–3 A load.
It integrates undervoltage lockout (UVLO threshold 2.45 V, 150 mV hysteresis), thermal shutdown (160°C, 10°C hysteresis), and overcurrent protection (5.8 A short-circuit limit). Soft-start is implemented via internal 13.5 kΩ resistor charging external CSS, with enable logic referenced to VBIAS and 100 mV hysteresis.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Current | 3 A maximum continuous - supports high-current digital loads like FPGA cores without external current boosting. |
| Dropout Voltage | 240 mV typical at 3 A - enables regulation from VIN as low as VOUT + 0.24 V, critical for low-voltage system rails. |
| VOUT Accuracy | ±2% over –40°C to +125°C - ensures stable core voltage under thermal stress in servers and embedded systems. |
| VBIAS Range | 3 V to 5.5 V - must be ≥4.5 V when VOUT > 1.2 V; decouples gate drive from power path for efficiency. |
| Soft-Start Time | 675 µs with 10 nF CSS - limits inrush current into COUT during power-up, preventing supply sag or reset glitches. |
| PSRR @ 1 kHz | 70 dB (VIN), 58 dB (VBIAS) - suppresses switching noise from upstream SMPS or bias rails in mixed-signal systems. |
| Operating Temp | –40°C to +125°C junction - qualified for industrial and telecom infrastructure environments. |
Pinout & Package
LP38853SX-ADJ/NOPB is packaged in 7-pin DDPAK/TO-263 (KTW), with exposed thermal tab electrically connected to GND. The package measures 10.10 mm × 8.89 mm and requires PCB copper pour under the tab for thermal management.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| IN | Main power input | High-current path to NMOS source; must be ≥ VOUT + 240 mV and ≤ min(VBIAS, 4.5 V). |
| BIAS | Bias supply input | Powers internal reference, error amp, and gate driver; sets operational voltage window and UVLO behavior. |
| GND | Ground reference | Common return for IN, BIAS, and OUT paths; connects to thermal tab - must be low-impedance plane. |
| OUT | Regulated output | Delivers up to 3 A; requires 10-µF ceramic COUT placed near pin for stability and transient response. |
| ADJ | Feedback node | Connects to resistor divider (R1/R2); senses 500 mV reference - sets VOUT = 0.8–1.8 V via external ratio. |
| EN | Enable control | Active-high logic input (1.25 V threshold); internal 180-kΩ pullup to VBIAS - allows simple ON/OFF sequencing. |
| SS | Soft-start capacitor | Charged by internal 13.5-kΩ resistor; controls VOUT ramp rate - open if soft-start not required. |
Key Features
| Feature | Design Value |
|---|---|
| Dual-rail input architecture | VIN supplies load current; VBIAS powers control circuitry - enables <1-V VIN operation while preserving regulation accuracy. |
| Ultra-low dropout | 240 mV at 3 A - minimizes power loss and heat generation in high-current, low-voltage applications. |
| Stable with ceramic capacitors | Requires only 10-µF COUT - eliminates need for costly tantalum or electrolytic caps, reducing BOM cost and footprint. |
| Programmable soft-start | Timing set by external CSS (1–100 nF) and internal 13.5-kΩ resistor - prevents inrush-induced voltage droop on shared rails. |
| Integrated protection | Thermal shutdown (160°C), overcurrent limiting (5.8 A), and UVLO (2.45 V) - eliminates need for external fault management circuitry. |
Applications
| ASIC Core Power | Server I/O Supply |
|---|---|
Use Scenario: Powers CPU/GPU core logic in desktops, notebooks, and graphics cards where tight voltage tolerance and fast transient response are mandatory. IC Role / Device Role / Timing Role: Primary low-noise, high-accuracy LDO delivering dynamically scaled core voltage (0.8–1.2 V) with sub-2% error across temperature. Use Value: Maintains processor stability during burst-mode execution by rejecting 70 dB of 1-kHz switching noise from upstream DC/DC converters. |
Use Scenario: Supplies PCIe, SATA, and memory interface rails in rack-mounted servers requiring clean, sequenced 1.2–1.8 V outputs. IC Role / Device Role / Timing Role: Post-regulator after intermediate bus converters, providing precise voltage with programmable soft-start for inrush control. Use Value: Enables safe hot-plug sequencing via EN pin and avoids brownout during power-up by limiting dV/dt with CSS-controlled ramp. |
| FPGA Core Regulation | SMPS Post-Regulator |
Use Scenario: Delivers configurable core voltage (0.8–1.8 V) to Xilinx/Intel FPGAs in telecom baseband and test equipment. IC Role / Device Role / Timing Role: Adjustable LDO with ADJ-pin feedback loop - set via precision R1/R2 divider to match FPGA VCCINT requirements. Use Value: Achieves ±2% output accuracy over –40°C to +125°C, ensuring reliable configuration and operation in uncontrolled thermal environments. |
Use Scenario: Cleans residual ripple from high-efficiency buck converters powering DSPs, ADCs, or RF front-ends. IC Role / Device Role / Timing Role: Low-noise linear post-regulator with 150 µVRMS output noise (10 Hz–100 kHz) and 70-dB PSRR at 1 kHz. Use Value: Reduces switching artifacts that degrade SNR in analog signal chains - critical for 16-bit+ data converters. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS7A8300RGRT | 3-A, 50-µVRMS noise, 75-dB PSRR @ 1 kHz, but requires single 1.4–6.5 V input (no VBIAS rail) | Better noise/PSRR, but cannot operate below VIN = VOUT + 300 mV - unsuitable for ultra-low VIN use cases | Select when lowest noise is priority and input voltage margin permits; avoid when VBIAS decoupling is needed for gate drive. |
| LP38798SD-ADJ/NOPB | 2-A, same VBIAS architecture, 180-mV dropout, but only rated to +105°C junction and lacks SS pin | Limited thermal capability and no programmable soft-start - insufficient for 125°C server or high-inrush FPGA apps | Acceptable for lower-power, lower-temp industrial designs; not drop-in due to missing SS functionality and reduced current/temp rating. |
Compared with TPS7A8300RGRT and LP38798SD-ADJ/NOPB, the LP38853SX-ADJ/NOPB uniquely balances 3-A capability, dual-rail flexibility, 125°C operation, and soft-start programmability - making it optimal for thermally demanding, high-current, multi-rail systems where VIN headroom is constrained.
Availability
LP38853SX-ADJ/NOPB is available at Aetrix Electronics and suitable for FPGA core power, server I/O supplies, and SMPS post-regulation requiring stable component supply, long-term lifecycle support, and traceable sourcing for production programs.
Supply support for LP38853SX-ADJ/NOPB 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 company specializing in analog and embedded processing technologies, with leadership in power management ICs and high-reliability industrial components.
The LP38853SX-ADJ/NOPB belongs to TI's high-current LDO family designed specifically for fast-transient, low-dropout regulation in computing, networking, and telecom infrastructure - emphasizing thermal robustness, accuracy, and bias-rail flexibility.
FAQ
What is the minimum VBIAS voltage required for LP38853SX-ADJ/NOPB to operate at VOUT = 1.0 V?
The LP38853SX-ADJ/NOPB requires a minimum VBIAS of 3 V when VOUT is set to 1.0 V, as specified in the Recommended Operating Conditions table. This ensures proper gate drive for the NMOS pass element and maintains ±2% output accuracy across temperature. Operating below 3 V risks UVLO activation or degraded regulation performance.
Can LP38853SX-ADJ/NOPB be used with VOUT = 1.5 V while VBIAS = 3.3 V?
No - LP38853SX-ADJ/NOPB requires VBIAS ≥ 4.5 V when VOUT exceeds 1.2 V. At VOUT = 1.5 V and VBIAS = 3.3 V, the device may fail to regulate correctly or exhibit increased dropout and accuracy drift. For 1.5 V output, VBIAS must be set between 4.5 V and 5.5 V per the datasheet's operating conditions.
How is the soft-start time calculated for LP38853SX-ADJ/NOPB?
The soft-start time for LP38853SX-ADJ/NOPB is calculated as tSS = CSS × rSS × 5, where rSS = 13.5 kΩ (typical internal resistance at SS pin) and CSS is the external capacitor value. For example, with CSS = 10 nF, tSS = 675 µs. This exponential ramp ensures controlled VOUT rise and limits inrush current into COUT.
Does LP38853SX-ADJ/NOPB require an external bypass capacitor on the BIAS pin?
Yes - the LP38853SX-ADJ/NOPB requires a 1-µF ceramic capacitor (CBIAS) connected between BIAS and GND, placed close to the pin. This stabilizes the bias rail against transients and ensures consistent gate drive and reference performance, especially during load steps or enable transitions.
What is the maximum allowable output capacitance for LP38853SX-ADJ/NOPB?
The LP38853SX-ADJ/NOPB is stable with ≥10-µF ceramic output capacitance and does not specify a maximum COUT value. However, larger COUT values increase inrush current during soft-start and may require proportionally larger CSS to maintain controlled ramp rate - design validation is recommended for COUT > 100 µF.
LP38853SX-ADJ/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- TO-263-8, D2PAK (7 Leads + Tab), TO-263CA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Configuration:
- Positive
- Output Type:
- Adjustable
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- 0.8V
- Voltage - Output (Max):
- 1.8V
- Voltage Dropout (Max):
- 0.45V @ 3A
- Current - Output:
- 3A
- Current - Quiescent (Iq):
- 300 µA
- Current - Supply (Max):
- 9 mA
- PSRR:
- 80dB ~ 70dB (120Hz ~ 1kHz)
- Control Features:
- Enable, Soft Start
- Protection Features:
- Over Current, Over Temperature, Short Circuit, Under Voltage Lockout (UVLO)
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-263 (DDPAK-7)
LP38853SX-ADJ/NOPB FAQ
1.How can I place an order for LP38853SX-ADJ/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LP38853SX-ADJ/NOPB 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 LP38853SX-ADJ/NOPB reliable?
The price and inventory of LP38853SX-ADJ/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LP38853SX-ADJ/NOPB is usually 5 days.
3.What payment methods are accepted for LP38853SX-ADJ/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LP38853SX-ADJ/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LP38853SX-ADJ/NOPB?
LP38853SX-ADJ/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LP38853SX-ADJ/NOPB 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 LP38853SX-ADJ/NOPB?
For technical support, including LP38853SX-ADJ/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LP38853SX-ADJ/NOPB requirements.
6.How does Aetrix verify that LP38853SX-ADJ/NOPB is sourced from the original manufacturer or authorized distributors?
All LP38853SX-ADJ/NOPB 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 LP38853SX-ADJ/NOPB meets industry standards.
7.What is the process for return or replacement of LP38853SX-ADJ/NOPB?
All LP38853SX-ADJ/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LP38853SX-ADJ/NOPB, 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 LP38853SX-ADJ/NOPB part is unused and in its original packaging.
Return procedure for LP38853SX-ADJ/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LP38853SX-ADJ/NOPB Tags
-
MIC5504-1.8YM5-TR
Microchip Technology
-
MIC5504-3.3YM5-TR
Microchip Technology
-
MIC5365-3.0YC5-TR
Microchip Technology
-
MIC5365-1.8YC5-TR
Microchip Technology
-
MIC5365-2.5YC5-TR
Microchip Technology
-
MIC5365-3.3YC5-TR
Microchip Technology
-
MIC5365-3.3YD5-TR
Microchip Technology
-
MIC5317-3.3YM5-TR
Microchip Technology
-
TLV1117LV33DCYR
Texas Instruments
-
MIC5317-3.3YMT-TZ
Microchip Technology
-
MIC5528-3.3YMT-TR
Microchip Technology
-
TLV75801PDRVR
Texas Instruments
Tech Hub
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…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
