My Inquiry
My Account
Texas Instruments LP38856SX-1.2/NOPB
- Part No.:
- LP38856SX-1.2/NOPB
- Manufacturer:
- Texas Instruments
- Package:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Datasheet:
-
LP38856SX-1.2/NOPB.pdf
- Description:
- IC REG LIN 1.2V 3A DDPAK/TO263-5
- Quantity:
- Payment:
- Shipping:
Inventory:1,071
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LP38856SX-1.2/NOPB from Texas Instruments is a 3-A, fast-response, high-accuracy LDO linear regulator with dual-rail operation (VIN and VBIAS), fixed 1.2 V output, 240 mV typical dropout at full load, ±1% output tolerance at 25°C, and stable operation with 10-µF ceramic output capacitance - used for powering microcontroller cores and FPGA I/O rails in compact power systems.
For engineers reviewing the LP38856SX-1.2/NOPB datasheet, LP38856SX-1.2/NOPB pinout, LP38856SX-1.2/NOPB application, or LP38856SX-1.2/NOPB equivalent, key selection considerations include its dual-supply architecture (VIN + VBIAS), ultra-low ground current (10 mA typ. at 3 A), 1 µA shutdown current, thermal/overcurrent protection, and compatibility with low-ESR ceramic capacitors without external compensation.
Technical Context
The LP38856SX-1.2/NOPB uses an N-MOS pass transistor driven by a separate VBIAS rail (3–5.5 V), enabling regulation from VIN as low as VOUT + VDO (≥1.44 V) while maintaining high bandwidth and fast transient response. Its CMOS control circuitry draws minimal quiescent current independent of load.
It integrates undervoltage lockout (UVLO threshold 2.45 V, 150 mV hysteresis), thermal shutdown (160°C), foldback overcurrent protection, and enable-controlled startup with 100 mV hysteresis on the EN pin. The device operates across –40°C to +125°C junction temperature with ±2% output accuracy over full temperature and load range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 1.2 V - eliminates external feedback resistors and simplifies layout for point-of-load applications. |
| Max Output Current | 3 A continuous - supports high-current digital loads including DSP cores and FPGA I/O banks. |
| Dropout Voltage | 240 mV (typ.) at 3 A - enables operation with minimal input headroom, e.g., 1.44 V input for 1.2 V output. |
| Output Accuracy | ±1% at TJ = 25°C; ±2% over 0°C to +125°C - ensures stable voltage margin for sensitive logic interfaces. |
| Ground Pin Current | 10 mA (typ.) at 3 A load - reduces power loss and PCB trace heating compared to bipolar LDOs. |
| Shutdown Current | 1 µA (typ.) - enables ultra-low-power system sleep modes without external disconnect switches. |
| PSRR @ 1 kHz | 65 dB (VIN), 58 dB (VBIAS) - suppresses switching noise from upstream SMPS or bias supplies. |
| Stability | Guaranteed with ≥10 µF ceramic COUT (X5R/X7R) - eliminates need for series ESR or compensation networks. |
Pinout & Package
LP38856SX-1.2/NOPB is housed in a 5-pin DDPAK/TO-263 package (10.16 mm × 8.42 mm) with exposed thermal tab electrically connected to GND. The tab serves as primary thermal path to PCB copper and must be soldered to a dedicated thermal pad.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - EN | Enable input | Active-high logic control; internal 180-kΩ pull-up to VBIAS; 1.25 V threshold with 100 mV hysteresis. |
| 2 - IN | Main power input | High-current path supplying load; must be ≥VOUT + VDO and ≤VBIAS; requires ≥10 µF ceramic capacitor. |
| 3 - GND | Analog/digital ground | Common reference for IN, OUT, BIAS, and EN; connects to thermal tab; requires low-inductance Kelvin return. |
| 4 - OUT | Regulated output | Delivers 1.2 V at up to 3 A; requires ≥10 µF ceramic capacitor placed within 1 cm and returned directly to GND pin. |
| 5 - BIAS | Bias supply input | Powers internal reference, error amplifier, and gate driver; 3–5.5 V range; requires ≥1 µF ceramic capacitor. |
Key Features
| Feature | Design Value |
|---|---|
| Dual-rail input architecture | VIN handles high-current load path; VBIAS powers control circuitry - enables ultra-low VIN operation without sacrificing speed or accuracy. |
| Fast transient response | Sub-20 µs turn-on delay and <50 µs load-step recovery (with 10 µF COUT) - maintains core voltage during CPU burst activity. |
| Integrated protection | Thermal shutdown (160°C, 10°C hysteresis) and foldback current limiting - prevents damage during overload or poor heatsinking. |
| Low-noise regulation | 150 µVRMS output noise (10 Hz–100 kHz) - suitable for noise-sensitive analog peripherals and PLL power domains. |
| Supply sequencing flexibility | No strict VIN/VBIAS power-up order required - simplifies multi-rail system design and avoids sequencing ICs. |
Applications
| Microcontroller Core Supply | FPGA I/O Bank Regulation |
|---|---|
|
Use Scenario: Powering ARM Cortex-A/M series SoC cores requiring tightly regulated 1.2 V at up to 3 A with fast dynamic response. IC Role / Device Role / Timing Role: Primary low-dropout post-regulator delivering clean, stable core voltage synchronized to processor activity. Use Value: 240 mV dropout enables use of intermediate bus voltages (e.g., 1.5 V or 1.8 V), reducing power loss vs. higher-input LDOs. |
Use Scenario: Providing compliant 1.2 V I/O supply for Xilinx Artix/Kintex or Intel Cyclone FPGA banks with simultaneous switching noise immunity. IC Role / Device Role / Timing Role: Dedicated LDO per I/O bank ensuring voltage integrity during high-speed data transfers and configuration loading. Use Value: 65 dB PSRR at 1 kHz attenuates SMPS ripple, preventing timing jitter and bit errors in high-speed SerDes links. |
| SMPS Post-Regulator | Server Memory Buffer Supply |
|
Use Scenario: Tightening output voltage tolerance and suppressing residual ripple from a 1.5 V buck converter feeding DDR memory subsystems. IC Role / Device Role / Timing Role: Precision post-regulator correcting line/load variations and high-frequency noise from upstream switching stage. Use Value: ±1% output accuracy over temperature ensures DDR4/5 VDDQ compliance margins remain intact under thermal stress. |
Use Scenario: Delivering 1.2 V to RDIMM or LRDIMM register buffers and data buffer ICs in enterprise servers. IC Role / Device Role / Timing Role: High-current, thermally robust LDO supporting burst-mode memory access with minimal voltage droop. Use Value: 10 mA typical ground current at 3 A load minimizes board-level IR drop and improves system efficiency at full memory bandwidth. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS7A8300RGRT | Single-rail input (2.2–6.5 V), 3-A, 1.2 V fixed, 115 mV dropout, 20 µA IQ - no VBIAS rail required. | Better suited for space-constrained designs where only one input rail is available; lower dropout but higher quiescent current. | Select when VIN ≥ 1.315 V and board area limits use of dual-rail layout; not drop-in due to different pinout and bias architecture. |
| TPS7A8400RGRT | Single-rail input (1.1–6.5 V), 3-A, adjustable or fixed 1.2 V, 130 mV dropout, 2.5 µA shutdown - includes soft-start. | Offers programmable soft-start and higher PSRR (75 dB @ 100 kHz); lacks VBIAS flexibility for ultra-low VIN cases. | Prefer when controlled ramp-up is needed to prevent inrush or when higher mid-band PSRR is critical; requires external feedback for fixed 1.2 V. |
Compared with TPS7A8300RGRT and TPS7A8400RGRT, the LP38856SX-1.2/NOPB uniquely supports VIN as low as 1.44 V via separate VBIAS, delivers lower ground current at full load, and guarantees stability with minimal 10-µF ceramic output capacitance - making it optimal for thermally demanding, dual-rail embedded systems.
Availability
LP38856SX-1.2/NOPB is available at Aetrix Electronics and suitable for server core supplies, FPGA I/O regulation, and SMPS post-regulation requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.
Supply support for LP38856SX-1.2/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 leader designing analog ICs, embedded processors, and connectivity solutions for industrial, automotive, and communications markets.
The LP38856SX-1.2/NOPB belongs to TI's high-current LDO family engineered for fast transient response and precision regulation in power-hungry digital systems - targeting core voltage delivery for microcontrollers, FPGAs, and ASICs where efficiency, thermal performance, and noise rejection are critical.
FAQ
What is the minimum input voltage required for LP38856SX-1.2/NOPB to regulate 1.2 V output?
The LP38856SX-1.2/NOPB requires VIN ≥ VOUT + VDO, where VDO is 240 mV (typical) at 3 A. Thus, minimum VIN is 1.44 V under typical full-load conditions. However, actual minimum depends on temperature and load - at –40°C and 3 A, VDO rises to 450 mV, requiring VIN ≥ 1.65 V. Always verify against worst-case electrical characteristics in the datasheet.
Can LP38856SX-1.2/NOPB operate with only one supply rail?
No - LP38856SX-1.2/NOPB requires two independent supplies: VIN (for power delivery to the load) and VBIAS (3–5.5 V, for internal circuitry and gate drive). Using a single rail violates operating conditions and may cause malfunction or damage. If only one rail is available, consider TI's TPS7A8300RGRT or TPS7A8400RGRT as alternatives.
What capacitor types and values are mandatory for stable operation of LP38856SX-1.2/NOPB?
LP38856SX-1.2/NOPB requires three capacitors: ≥10 µF X5R/X7R ceramic on IN, ≥10 µF X5R/X7R ceramic on OUT (placed ≤1 cm from OUT pin and returned directly to GND pin), and ≥1 µF ceramic on BIAS. Z5U/Y5F ceramics are unsuitable due to capacitance loss over temperature. Tantalum may be added in parallel with the output ceramic but is not a substitute.
Does LP38856SX-1.2/NOPB include reverse-voltage protection?
LP38856SX-1.2/NOPB has no integrated reverse-voltage protection. Its N-MOS pass transistor lacks a body diode, so reverse current flows only when VBIAS > UVLO threshold and VIN < VOUT - a condition outside specification. To prevent damage during reverse bias (e.g., hot-swap or backup battery scenarios), external Schottky clamping diodes are recommended per TI's application guidance.
How does the EN pin function on LP38856SX-1.2/NOPB, and what happens if left unconnected?
The EN pin on LP38856SX-1.2/NOPB is active-high with internal 180-kΩ pull-up to VBIAS. Driving EN ≥1.25 V (typ.) enables regulation; ≤1 V disables it, reducing IIN(GND) to 1 µA. If left floating, stray capacitance may delay startup as the internal resistor charges the node - TI recommends connecting EN directly to VBIAS if enable control is unused.
LP38856SX-1.2/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- 1.2V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.45V @ 3A
- Current - Output:
- 3A
- Current - Quiescent (Iq):
- 300 µA
- Current - Supply (Max):
- 15 mA
- PSRR:
- 80dB ~ 65dB (120Hz ~ 1kHz)
- Control Features:
- Enable
- 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-5)
LP38856SX-1.2/NOPB FAQ
1.How can I place an order for LP38856SX-1.2/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LP38856SX-1.2/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 LP38856SX-1.2/NOPB reliable?
The price and inventory of LP38856SX-1.2/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LP38856SX-1.2/NOPB is usually 5 days.
3.What payment methods are accepted for LP38856SX-1.2/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LP38856SX-1.2/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LP38856SX-1.2/NOPB?
LP38856SX-1.2/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LP38856SX-1.2/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 LP38856SX-1.2/NOPB?
For technical support, including LP38856SX-1.2/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LP38856SX-1.2/NOPB requirements.
6.How does Aetrix verify that LP38856SX-1.2/NOPB is sourced from the original manufacturer or authorized distributors?
All LP38856SX-1.2/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 LP38856SX-1.2/NOPB meets industry standards.
7.What is the process for return or replacement of LP38856SX-1.2/NOPB?
All LP38856SX-1.2/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LP38856SX-1.2/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 LP38856SX-1.2/NOPB part is unused and in its original packaging.
Return procedure for LP38856SX-1.2/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LP38856SX-1.2/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.…
