My Inquiry
My Account
Texas Instruments LP3984IMFX-1.8
- Part No.:
- LP3984IMFX-1.8
- Manufacturer:
- Texas Instruments
- Package:
- SC-74A, SOT-753
- Datasheet:
-
LP3984IMFX-1.8.pdf
- Description:
- IC REG LINEAR 1.8V 150MA SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:2,325
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LP3984IMFX-1.8 from Texas Instruments is a micropower 150 mA ultra-low-dropout CMOS voltage regulator in a 5-pin SOT-23 package, delivering a fixed 1.8 V output with ≤75 mV dropout at full load, 60 dB PSRR at 1 kHz, and 1.2 µA shutdown current - optimized for battery-powered CDMA/GSM handsets and portable information appliances.
For engineers reviewing the LP3984IMFX-1.8 datasheet, LP3984IMFX-1.8 pinout, LP3984IMFX-1.8 application, or LP3984IMFX-1.8 equivalent, key selection considerations include its 2.5–6.0 V input range, logic-controlled enable (VEN), stability with 1 µF tantalum output capacitor, fast 20 µs turn-on time, and −40°C to +125°C operating junction temperature.
Technical Context
The LP3984IMFX-1.8 employs a CMOS pass transistor architecture enabling ultra-low quiescent current and minimal ground current increase in dropout - critical for extending battery life in portable wireless systems. Its internal bandgap reference and error amplifier deliver tight output regulation with ±1.2% initial tolerance and <0.15%/V line regulation.
Designed for low-noise, high-PSRR operation, it maintains 60 dB power supply rejection at 1 kHz and 40 dB at 10 kHz while supporting stable operation with 1–22 µF tantalum output capacitors (2–10 Ω ESR). Thermal shutdown (160°C) and short-circuit current limiting (600 mA) provide robust protection without external components.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 1.8 V ±1.2% - ensures precise core voltage for 1.8 V logic rails in mobile baseband processors. |
| Max Output Current | 150 mA - sufficient to power RF transceivers, memory, or microcontrollers in compact handheld devices. |
| Dropout Voltage | 75 mV typ. at 150 mA - enables regulation down to VIN = 1.875 V, maximizing usable battery capacity in single-cell Li-ion or Li-poly systems. |
| Quiescent Current | ≤1.2 µA in shutdown - minimizes standby leakage, critical for always-on functions like RTC or RAM keep-alive. |
| PSRR | 60 dB @ 1 kHz, 40 dB @ 10 kHz - suppresses switching noise from PMICs or DC/DC converters feeding the LDO input. |
| Enable Threshold | VIL ≤0.4 V, VIH ≥1.4 V - compatible with 1.8 V GPIOs and supports direct connection to battery or system power rails. |
| Operating Temp | −40°C to +125°C junction - qualified for automotive infotainment modules and industrial handheld terminals. |
Pinout & Package
SOT-23-5 package (Package Drawing DBV), 2.9 mm × 1.6 mm footprint, 1.1 mm max height, RoHS-compliant lead finish (CuSn), moisture sensitivity level 1 (260°C peak reflow).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN (Pin 1) | Input voltage supply | Accepts 2.5–6.0 V; requires ≥1 µF input capacitor placed within 1 cm of pin for stability. |
| GND (Pin 2) | Power ground reference | Common return path for input/output currents; must connect to clean analog ground plane. |
| VEN (Pin 3) | Logic-enable control input | Active-high enable; pulls low (<0.4 V) to disable regulator and reduce IQ to ≤1.2 µA. |
| VOUT (Pin 5) | Regulated output | Delivers fixed 1.8 V; requires 1–22 µF tantalum capacitor (2–10 Ω ESR) for loop stability. |
| N.C. (Pin 4) | No connection | Unbonded pad; must remain unconnected on PCB - no routing or thermal relief required. |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low shutdown current | ≤1.2 µA - extends shelf life and standby runtime in battery-backed applications like smartcards or IoT sensors. |
| Tantalum-capacitor compatibility | Stable with 1 µF minimum tantalum output cap - eliminates need for larger, more expensive ceramic alternatives in space-constrained layouts. |
| Fast turn-on response | 20 µs typical - enables rapid power sequencing for wake-from-sleep modes in cellular modems and Bluetooth SoCs. |
| High PSRR at low frequencies | 60 dB @ 1 kHz - effectively filters ripple from switch-mode power supplies powering baseband ICs. |
| Integrated protection | Thermal shutdown (160°C) and 600 mA short-circuit limit - prevents damage during overloads without external circuitry. |
Applications
| CDMA Cellular Handsets | Wideband CDMA Cellular Handsets |
|---|---|
Use Scenario: Powering RF transceiver bias rails and baseband processor I/O domains in dual-mode CDMA handsets. IC Role / Device Role / Timing Role: Primary 1.8 V LDO supplying noise-sensitive analog front-end circuits and digital I/O banks. Use Value: 60 dB PSRR at 1 kHz suppresses switching noise from adjacent DC/DC converters, preserving receiver sensitivity and reducing bit error rate. | Use Scenario: Regulating core voltage for WCDMA baseband ASICs requiring tight 1.8 V tolerance and fast transient response. IC Role / Device Role / Timing Role: Low-noise post-regulator following a buck converter, delivering stable 1.8 V under dynamic load steps up to 150 mA. Use Value: 20 µs turn-on time enables synchronous power-up with modem reset signals, eliminating boot delays in 3G data modules. |
| GSM Cellular Handsets | Portable Information Appliances |
Use Scenario: Supplying SIM card interface, display driver, and keypad controller in cost-sensitive GSM feature phones. IC Role / Device Role / Timing Role: General-purpose 1.8 V LDO with logic enable for selective subsystem power gating. Use Value: ≤1.2 µA shutdown current reduces parasitic drain during sleep mode, extending talk time by >12 hours per charge cycle. | Use Scenario: Powering low-power microcontrollers and sensor interfaces in handheld medical testers or barcode scanners. IC Role / Device Role / Timing Role: Micropower LDO maintaining 1.8 V rail during intermittent measurement cycles and deep-sleep intervals. Use Value: Stable operation with no-load condition supports RAM keep-alive functionality without external discharge paths or timing constraints. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPL720F18 | 200 mA output, 50 mV dropout at 150 mA, 2.5 µA quiescent current in shutdown | Higher output current and lower dropout, but higher IQ limits ultra-low-power use cases | Preferred when higher load margin or tighter dropout is needed; verify thermal derating in SOT-23-5 |
| MCP1700T-1802E/MB | 250 mA output, 175 mV dropout at 250 mA, 1.6 µA shutdown current, SOT-23-3 package | 3-pin variant lacks enable control; requires external resistor divider for adjustable versions | Selected for cost-sensitive designs where enable functionality is unnecessary and board space is constrained |
Compared with LP3984IMFX-1.8, TPL720F18 offers improved dropout and current capability at the expense of higher shutdown current, while MCP1700T-1802E/MB provides higher output current in a smaller 3-pin footprint but omits logic enable - making LP3984IMFX-1.8 optimal for applications demanding both micropower shutdown and precise 1.8 V regulation with enable control.
Availability
LP3984IMFX-1.8 is available at Aetrix Electronics and suitable for CDMA/GSM handset design, portable information appliance development, and industrial handheld terminal production requiring stable component supply across extended lifecycle windows.
Supply support for LP3984IMFX-1.8 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 headquartered in Dallas, Texas, specializing in analog, embedded processing, and connectivity technologies for industrial, automotive, and consumer markets.
The LP3984 series belongs to TI's precision low-dropout regulator product line, engineered specifically for space-constrained, battery-powered wireless devices demanding ultra-low IQ, fast transient response, and robust capacitor compatibility.
FAQ
What is the maximum input voltage rating for the LP3984IMFX-1.8?
The LP3984IMFX-1.8 has an absolute maximum input voltage (VIN) rating of 6.5 V, with recommended operating range from 2.5 V to 6.0 V. Exceeding 6.5 V risks permanent damage. For reliable operation in battery-powered systems, VIN should remain within specification - especially important when using fully charged Li-ion cells (up to 4.2 V) or stacked alkaline sources.
Does the LP3984IMFX-1.8 require an external bypass capacitor for noise reduction?
The LP3984IMFX-1.8 does not require an external bypass capacitor for basic operation, but adding one (e.g., 1–10 nF between VOUT and GND) can improve high-frequency PSRR and reduce output noise. The device achieves 90 µVrms output noise with a 1 µF tantalum capacitor; a small ceramic bypass further attenuates broadband noise above 100 kHz without affecting stability.
Can the LP3984IMFX-1.8 be used with ceramic output capacitors instead of tantalum?
The LP3984IMFX-1.8 is explicitly characterized and stabilized for use with tantalum capacitors (1–22 µF, 2–10 Ω ESR). While some ceramic capacitors may function, TI does not guarantee stability with low-ESR ceramics due to potential phase-margin degradation. If ceramic is required, thorough bench validation across temperature and load transients is mandatory before deployment.
What is the thermal shutdown hysteresis of the LP3984IMFX-1.8?
The LP3984IMFX-1.8 features thermal shutdown activation at 160°C junction temperature, with 20°C hysteresis - meaning the device resumes normal operation only after junction temperature falls to approximately 140°C. This prevents oscillatory shutdown/restart during sustained high-power dissipation in confined enclosures or high ambient temperatures.
Is the LP3984IMFX-1.8 pin-compatible with other variants in the LP3984 family?
Yes - all LP3984 variants (e.g., LP3984IMF-1.5/NOPB, LP3984IMF-3.1/NOPB) share identical SOT-23-5 pinout (VIN, GND, VEN, N.C., VOUT), enabling drop-in replacement across output voltages without PCB redesign. The LP3984IMFX-1.8 retains full functional and mechanical compatibility, differing only in output voltage trim and marking.
LP3984IMFX-1.8 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 6V
- Voltage - Output (Min/Fixed):
- 1.8V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.12V @ 150mA
- Current - Output:
- 150mA
- Current - Quiescent (Iq):
- 125 µA
- Current - Supply (Max):
- 150 µA
- PSRR:
- 60dB ~ 40dB (1kHz ~ 10kHz)
- Control Features:
- Enable
- Protection Features:
- Over Temperature, Short Circuit
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
LP3984IMFX-1.8 FAQ
1.How can I place an order for LP3984IMFX-1.8 through Aetrix?
Please submit a Request for Quotation (RFQ) for LP3984IMFX-1.8 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 LP3984IMFX-1.8 reliable?
The price and inventory of LP3984IMFX-1.8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LP3984IMFX-1.8 is usually 5 days.
3.What payment methods are accepted for LP3984IMFX-1.8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LP3984IMFX-1.8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LP3984IMFX-1.8?
LP3984IMFX-1.8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LP3984IMFX-1.8 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 LP3984IMFX-1.8?
For technical support, including LP3984IMFX-1.8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LP3984IMFX-1.8 requirements.
6.How does Aetrix verify that LP3984IMFX-1.8 is sourced from the original manufacturer or authorized distributors?
All LP3984IMFX-1.8 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 LP3984IMFX-1.8 meets industry standards.
7.What is the process for return or replacement of LP3984IMFX-1.8?
All LP3984IMFX-1.8 units undergo pre-shipment inspection (PSI). If there is an issue with LP3984IMFX-1.8, 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 LP3984IMFX-1.8 part is unused and in its original packaging.
Return procedure for LP3984IMFX-1.8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LP3984IMFX-1.8 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…
