My Inquiry
My Account
Analog Devices Inc. LT1965IQ#TRPBF
- Part No.:
- LT1965IQ#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Datasheet:
-
LT1965IQ#TRPBF.pdf
- Description:
- IC REG LIN POS ADJ 1.1A 5DDPAK
- Quantity:
- Payment:
- Shipping:
Inventory:694
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT1965IQ#TRPBF from Analog Devices (formerly Linear Technology) is a 1.1A, low-noise, adjustable-output LDO linear regulator in a 5-lead DD-Pak package with –40°C to 125°C operating junction temperature range. It delivers 1.1A output current with 310mV typical dropout at full load, 40µVRMS output noise (10Hz–100kHz), and <1µA shutdown quiescent current - optimized for RF power supply filtering and post-regulation of switching converters.
For engineers reviewing the LT1965IQ#TRPBF datasheet, LT1965IQ#TRPBF pinout, LT1965IQ#TRPBF application, or LT1965IQ#TRPBF equivalent, this page provides verified circuit role (adjustable positive LDO), thermal performance (θJA = 30°C/W), stability conditions (stable with ≥10µF ceramic/tantalum), protection features (reverse-battery, reverse-current, foldback current limit), and validated alternative options for industrial and battery-powered systems.
Technical Context
The LT1965IQ#TRPBF implements a PNP-based pass transistor architecture with internal error amplifier referenced to a precision 1.20V ADJ pin voltage. Its controlled quiescent current remains stable across dropout - unlike many LDOs - enabling predictable thermal behavior during input voltage sag. The device uses Kelvin-sense-capable feedback via the ADJ pin, supporting remote sensing for high-accuracy regulation under PCB trace resistance.
It integrates reverse-battery protection (no external diode required), thermal limiting with automatic recovery, and foldback current limiting that reduces output current during short-circuit events. Shutdown is logic-controlled via the SHDN pin, with threshold defined as 0.2V (off-to-on) and 0.85V (on-to-off), compatible with standard CMOS/TTL interfaces.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Current | 1.1A continuous - supports high-current analog/RF loads without derating at TJ ≤ 125°C |
| Dropout Voltage | 310mV typical at 1.1A - enables operation with minimal VIN–VOUT margin (e.g., 3.3V out from 3.6V Li-ion) |
| Output Noise | 40µVRMS (10Hz–100kHz) - meets stringent spectral purity requirements for RF transceivers and ADC reference supplies |
| Quiescent Current | 500µA active / <1µA shutdown - extends battery life in always-on sensor nodes and portable instrumentation |
| Input Voltage Range | 1.8V to 20V - accommodates wide-input sources including multi-cell batteries and unregulated DC rails |
| Output Voltage Range | Adjustable 1.20V to 19.5V - configured via external resistor divider; ADJ pin voltage fixed at 1.20V ±18mV |
| Stability | Stable with ≥10µF ceramic or tantalum output capacitor - eliminates need for ESR-tuned capacitors |
Pinout & Package
LT1965IQ#TRPBF is housed in a thermally enhanced 5-lead Plastic DD-Pak package (θJA = 30°C/W, θJC = 3°C/W) with exposed tab soldered to PCB ground for optimal heat dissipation. The package is RoHS-compliant and lead-free.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1, 2 - OUT | Power Output | Dual-source output pins reduce IR drop and improve current sharing; requires ≥10µF output capacitance for stability |
| 3 - ADJ | Feedback Reference Input | Serves as error amplifier inverting input; biased at 1.20V; 1.3µA bias current flows into pin - impacts resistor divider accuracy |
| 4 - GND | Ground Reference | Main signal and thermal ground; connects internally to exposed tab; must be low-impedance for regulation accuracy |
| 5 - SHDN | Shutdown Control | Active-low logic input; pulls output off when <0.45V; draws <5.5µA; unused pin must connect to VIN |
| - Tab | Thermal Ground | Exposed copper pad (GND); mandatory solder connection to PCB ground plane for thermal performance and EMI reduction |
Key Features
| Feature | Design Value |
|---|---|
| Reverse-Battery Protection | Withstands –20V on IN pin without damage or reverse current - eliminates need for external series diode in battery inputs |
| No Reverse-Output Current | Blocks current flow from OUT to GND when IN = 0V - prevents backfeeding in redundant supply or hot-swap applications |
| Controlled Quiescent Current in Dropout | IQ remains ~500µA even as VIN approaches VOUT - avoids thermal runaway and enables predictable power budgeting |
| Thermally Enhanced DD-Pak | θJA = 30°C/W - delivers 1.1A output with <25°C rise above ambient at 25°C ambient, simplifying heatsink design |
| Fixed 1.20V Reference Accuracy | ADJ pin voltage = 1.182V to 1.218V over –40°C to 125°C - enables ±2% output tolerance with 1% resistors |
| Current Limit with Foldback | 1.1A nominal limit dropping to ~0.5A during sustained short - reduces power dissipation and junction temperature during faults |
Applications
| RF Power Amplifier Bias Supply | Post-Regulator for Buck Converter Outputs |
|---|---|
|
Use Scenario: Providing clean, low-noise 2.8V bias to GaAs pHEMT power amplifiers in cellular base station transceivers. IC Role / Device Role / Timing Role: Low-noise LDO delivering stable 1.1A current with minimal ripple-induced AM-to-PM distortion. Use Value: 40µVRMS noise ensures EVM degradation <0.3% at 2.6GHz; 310mV dropout allows direct use of 3.3V intermediate rail. |
Use Scenario: Tightening output regulation and reducing switching noise from a 3.3V buck converter feeding an FPGA core rail. IC Role / Device Role / Timing Role: Precision post-regulator rejecting 100kHz–1MHz switching artifacts while maintaining fast transient response. Use Value: 75dB ripple rejection at 120Hz and >50dB up to 10kHz suppresses converter ripple; 10µF ceramic stability simplifies layout. |
| Portable Medical Sensor Node | Industrial PLC Analog I/O Module |
|
Use Scenario: Powering ultra-low-power EEG front-end ASICs and 24-bit delta-sigma ADCs from a single-cell Li-ion battery (2.7–4.2V). IC Role / Device Role / Timing Role: Adjustable LDO delivering 1.8V/3.3V with <1µA shutdown IQ to extend battery runtime between calibrations. Use Value: <1µA shutdown current enables >1-year shelf life; reverse-current blocking prevents battery drain during firmware updates. |
Use Scenario: Regulating isolated 5V or 3.3V rails for precision DACs, op-amps, and RS-485 transceivers in harsh factory environments. IC Role / Device Role / Timing Role: Robust LDO with thermal shutdown and foldback current limiting protecting against field wiring faults. Use Value: 150°C max junction temperature rating and reverse-battery tolerance withstand accidental 24V reverse polarity connections. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar adjustable LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS7A4701RGWR | Lower noise (4.7µVRMS), lower IQ (525µA), but 1A max output and 350mV dropout at 1A | Superior for ultra-low-noise audio/precision ADCs; less suitable for 1.1A continuous loads | Select when noise <5µVRMS is critical and load current ≤1A; verify thermal margin with θJA = 50°C/W |
| MCP1826T-ADJE/DC | Higher dropout (500mV at 1.1A), higher noise (80µVRMS), but wider temp range (–40°C to 150°C) | Better for under-hood automotive; insufficient for RF-sensitive designs requiring <50µVRMS | Prefer for cost-sensitive industrial controls where 80µVRMS noise and 500mV dropout are acceptable |
Compared with TPS7A4701RGWR and MCP1826T-ADJE/DC, the LT1965IQ#TRPBF uniquely balances 1.1A capability, 310mV dropout, and 40µVRMS noise in a thermally superior DD-Pak - making it optimal for space-constrained RF and high-accuracy analog systems where both current and spectral purity are non-negotiable.
Availability
LT1965IQ#TRPBF is available at Aetrix Electronics and suitable for RF power supply filtering, post-regulation of switching converters, and portable medical sensor node power management requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for LT1965IQ#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 acquired Linear Technology in 2017 and maintains its legacy of high-performance analog ICs, emphasizing precision, low noise, and robustness in power management and signal conditioning.
The LT1965IQ#TRPBF belongs to the LT1965 series of low-noise, high-current LDO regulators designed specifically for sensitive analog and RF power domains where switching noise rejection and thermal reliability are critical.
FAQ
What is the maximum output current specification for the LT1965IQ#TRPBF?
The LT1965IQ#TRPBF is rated for 1.1A continuous output current at junction temperatures ≤125°C. At higher temperatures (up to 150°C for H-grade variants), the current limit reduces to 1A per datasheet specifications. Derating curves confirm stable operation up to 1.1A with proper PCB thermal design using the exposed DD-Pak tab.
Does the LT1965IQ#TRPBF require an external diode for reverse-battery protection?
No, the LT1965IQ#TRPBF includes integrated reverse-battery protection and withstands –20V on the IN pin without external components. When reverse voltage is applied, the device behaves like a series diode - blocking reverse current and preventing damage to itself or downstream circuitry.
How does the LT1965IQ#TRPBF achieve low output noise compared to standard LDOs?
The LT1965IQ#TRPBF achieves 40µVRMS (10Hz–100kHz) noise through proprietary bandgap and error amplifier design, combined with low-noise pass transistor architecture. Its internal reference and feedback path are optimized to minimize flicker and thermal noise contributions - critical for powering RF synthesizers and high-resolution ADCs.
Can the LT1965IQ#TRPBF be used with ceramic output capacitors?
Yes, the LT1965IQ#TRPBF is explicitly characterized and guaranteed stable with ≥10µF ceramic or tantalum output capacitors - no minimum ESR requirement. This eliminates the need for aluminum electrolytic or specialty ESR-tuned capacitors, reducing board area and improving reliability.
What is the function of the ADJ pin on the LT1965IQ#TRPBF, and how is output voltage set?
The ADJ pin on the LT1965IQ#TRPBF serves as the feedback reference input to the error amplifier and is held at a precise 1.20V (±18mV) relative to GND. Output voltage is set by an external resistor divider: VOUT = 1.20V × (1 + R1/R2). ADJ pin bias current (1.3µA) flows into the pin and must be accounted for in high-accuracy designs.
Is the LT1965IQ#TRPBF pin-compatible with other packages in the LT1965 family?
No - the LT1965IQ#TRPBF uses a 5-lead DD-Pak footprint distinct from the 8-lead DFN, MSOP, or TO-220 variants. Pin functions (OUT, ADJ, GND, SHDN, IN) are consistent across packages, but physical layout, thermal pad configuration, and pin numbering differ. PCB redesign is required when substituting packages.
LT1965IQ#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Configuration:
- Positive
- Output Type:
- Adjustable
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 20V
- Voltage - Output (Min/Fixed):
- 1.2V
- Voltage - Output (Max):
- 19.5V
- Voltage Dropout (Max):
- 0.49V @ 1.1A
- Current - Output:
- 1.1A
- Current - Quiescent (Iq):
- 1.1 mA
- Current - Supply (Max):
- 40 mA
- PSRR:
- 75dB (120Hz)
- Control Features:
- Enable
- Protection Features:
- Over Current, Over Temperature, Reverse Polarity
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DDPAK-5
LT1965IQ#TRPBF FAQ
1.How can I place an order for LT1965IQ#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT1965IQ#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 LT1965IQ#TRPBF reliable?
The price and inventory of LT1965IQ#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT1965IQ#TRPBF is usually 5 days.
3.What payment methods are accepted for LT1965IQ#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT1965IQ#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT1965IQ#TRPBF?
LT1965IQ#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT1965IQ#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 LT1965IQ#TRPBF?
For technical support, including LT1965IQ#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT1965IQ#TRPBF requirements.
6.How does Aetrix verify that LT1965IQ#TRPBF is sourced from the original manufacturer or authorized distributors?
All LT1965IQ#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 LT1965IQ#TRPBF meets industry standards.
7.What is the process for return or replacement of LT1965IQ#TRPBF?
All LT1965IQ#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LT1965IQ#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 LT1965IQ#TRPBF part is unused and in its original packaging.
Return procedure for LT1965IQ#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT1965IQ#TRPBF 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 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…
