My Inquiry
My Account
Texas Instruments LM3280TL/NOPB
- Part No.:
- LM3280TL/NOPB
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Regulators - Linear + Switching
- Package:
- 16-WFBGA
- Datasheet:
-
LM3280TL/NOPB.pdf
- Description:
- IC REG QD BUCK/LNR 2MHZ 16TUSMD
- Quantity:
- Payment:
- Shipping:
Inventory:2,109
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM3280TL/NOPB from Texas Instruments is an integrated RF power management IC combining a synchronous step-down DC-DC converter (0.8V–3.6V output, 300mA PWM / 500mA bypass) and three independent 2.85V LDOs (20mA each), all in a single 16-pin DSBGA package. It enables dynamic PA voltage scaling in cellular handsets using analog VCON control (VOUT = 3 × VCON) and supports forced/automatic bypass mode for low-dropout operation during battery sag.
For engineers reviewing the LM3280TL/NOPB datasheet, LM3280TL/NOPB pinout, LM3280TL/NOPB application, or LM3280TL/NOPB equivalent, key selection criteria include its 2MHz PWM switching frequency, ±2% output voltage accuracy at 3.6V, 70mV typical dropout across LDOs at 20mA, thermal shutdown at 150°C, and discrete enable control per output - critical for multi-band RF PA sequencing and efficiency optimization in Li-ion-powered handheld devices.
Technical Context
The LM3280TL/NOPB implements a current-mode synchronous buck architecture with internal PFET/NFET switches and a dedicated bypass FET, enabling seamless transition between PWM regulation and direct battery feed. Its VCON analog input directly scales output voltage without external resistors, while independent digital ENBUCK, ENLDO1–3 pins allow precise power sequencing of RF power amplifier stages.
Operation includes three distinct modes: fixed-frequency PWM (2MHz typ.), forced bypass (via BYP pin), and automatic bypass (triggered when SVIN − VOUT falls below 160–320mV threshold). Each LDO features fast transient response (<100µs turn-on), 55dB PSRR at 1kHz, and active discharge on disable - essential for stable biasing of linear RF PAs under dynamic load conditions.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 2.7V to 5.5V - supports full discharge curve of single Li-ion cell without UVLO circuitry. |
| Buck Output Range | 0.8V to 3.6V - programmable via VCON (0.267V–1.200V); enables adaptive PA voltage scaling for efficiency. |
| LDO Output | 2.85V ±1% - tight tolerance ensures stable reference for RF PA bias networks. |
| Max Load Current | 300mA (PWM), 500mA (bypass) - accommodates peak PA current demands while minimizing dropout loss. |
| Switching Frequency | 2MHz (typ.) - avoids IF/data band interference and allows compact 2.2µH inductor + 4.7µF output cap design. |
| LDO Dropout Voltage | 70mV (typ.) at 20mA - minimizes conduction loss during high-current PA operation. |
| Shutdown Current | 0.1µA (typ.) - preserves battery life during deep sleep states in mobile handsets. |
Pinout & Package
The LM3280TL/NOPB uses a 16-bump DSBGA package (YZR0016QQA) with 0.5mm pitch, optimized for ultra-compact mobile PCB layouts.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A1 | LDO1 Output | Regulated 2.85V supply for Band 1 RF PA; enabled only when ENBUCK and ENLDO1 are high. |
| B1 | LDO2 Output | Regulated 2.85V supply for Band 2 RF PA; independent enable allows staggered PA activation. |
| C1 | LDO3 Output | Regulated 2.85V supply for Band 3 RF PA; supports multi-band handset architectures. |
| D1 | ENLDO3 | Digital enable input for LDO3; logic-high (>1.2V) activates output; pulled low disables LDO and discharges output. |
| A2 | SVIN | Analog/LDO supply input; must be decoupled separately from PVIN to minimize noise coupling into sensitive RF bias rails. |
| B2 | FB | Feedback node for buck regulator; connects directly to output capacitor to close voltage loop with ±2% accuracy. |
| C2 | ENLDO2 | Digital enable for LDO2; synchronized with ENBUCK to prevent LDO operation without buck regulation. |
| D2 | VCON | Analog control input; sets buck output as VOUT = 3 × VCON (0.267V–1.200V → 0.8V–3.6V range). |
| A3 | SGND | Analog/signal ground; separate from PGND to isolate noise-sensitive LDO and feedback paths. |
| B3 | ENBUCK | Main buck enable; must be held low until VIN >2.7V to prevent erratic startup; logic-high initiates PWM or bypass operation. |
| C3 | ENLDO1 | Digital enable for LDO1; enables Band 1 PA supply only after buck is active and stable. |
| D3 | BYP | Forced bypass mode control; low (<0.4V) enables direct battery feed to BYPOUT, bypassing PWM stage. |
| A4 | BYPOUT | Bypass FET drain; connects to output capacitor and PA supply rail; carries up to 500mA in bypass mode. |
| B4 | PVIN | Power input for buck switch and bypass FET; requires low-ESR bulk capacitance (10µF) near package. |
| C4 | SW | Switch node; connects to inductor; high dv/dt node requiring tight layout and ground shielding to reduce EMI. |
| D4 | PGND | Power ground for buck and bypass FETs; must be solid copper plane tied to PVIN capacitor ground. |
Key Features
| Feature | Design Value |
|---|---|
| Dynamic VCON-controlled buck output | Enables real-time PA voltage adjustment without external DAC or resistor network - reduces BOM count and layout area. |
| Independent per-output enable logic | Allows sequenced activation of three RF PAs (e.g., Band 1→2→3) to manage inrush current and avoid supply droop. |
| Automatic bypass mode with hysteresis | Transitions to low-dropout battery feed when SVIN − VOUT drops below 160–320mV, extending usable battery life during low-VIN operation. |
| Fast LDO turn-on time (50–100µs) | Meets GSM/EDGE burst timing requirements by delivering stable 2.85V within one RF frame period. |
| Thermal shutdown with 25°C hysteresis | Protects against sustained overload or poor heatsinking; resumes operation only after junction cools to ~125°C. |
Applications
| Cellular Handset PA Power Management | Multi-Band RF Front-End |
|---|---|
Use Scenario: Dynamic voltage scaling for GSM/EDGE/WCDMA power amplifiers across varying transmit power levels and battery voltages. IC Role / Device Role / Timing Role: LM3280TL/NOPB acts as the primary PA supply controller, generating programmable VOUT via VCON and delivering three isolated 2.85V LDO rails for PA biasing. Use Value: Achieves >96% efficiency at 120mA/3.2V output, extends talk time by reducing conversion loss during mid-power transmission. | Use Scenario: Simultaneous support of multiple RF bands (e.g., LTE Bands 1, 3, 7) requiring independent PA enable/disable control. IC Role / Device Role / Timing Role: LM3280TL/NOPB provides three digitally enabled 2.85V LDOs (LDO1–LDO3) with individual ENLDOx pins, allowing per-band PA activation. Use Value: Eliminates need for three discrete LDOs and associated enable logic, saving >12mm² PCB area in space-constrained smartphone designs. |
| Li-ion-Powered Portable Radios | Battery-Sensitive RF Test Equipment |
Use Scenario: Maintaining consistent PA output power over full 4.2V–3.0V Li-ion discharge curve in handheld two-way radios. IC Role / Device Role / Timing Role: LM3280TL/NOPB operates in automatic bypass mode when battery voltage approaches VOUT, minimizing dropout and preserving PA linearity. Use Value: Delivers stable RF output power down to 3.0V battery voltage - avoids premature transmitter shutdown during field use. | Use Scenario: Low-noise, low-drift bias supply for lab-grade RF power amplifiers requiring stable DC operating points during calibration. IC Role / Device Role / Timing Role: LM3280TL/NOPB supplies clean 2.85V LDO outputs with 55dB PSRR at 1kHz and <100µVpp ripple, rejecting supply noise from shared system rails. Use Value: Reduces measurement uncertainty in RF gain/linearity tests by eliminating supply-induced distortion in PA bias networks. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar RF power management applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS62740DSST | Single-output buck converter (up to 300mA), no integrated LDOs; requires external 2.85V LDOs for PA bias. | Not suitable for multi-PA biasing without added components; lacks VCON analog control and bypass FET. | Select when only buck regulation is needed and board space allows discrete LDO implementation. |
| TPS62865DRLR | Higher-current buck (1.2A), but no integrated LDOs or bypass mode; uses I²C interface instead of analog VCON. | Requires microcontroller coordination for PA voltage scaling; adds firmware complexity and communication overhead. | Prefer for high-power PAs where analog control is unnecessary and digital bus access is available. |
Compared with TPS62740DSST and TPS62865DRLR, the LM3280TL/NOPB uniquely integrates VCON-based analog voltage scaling, three independent LDOs, and automatic bypass - enabling simpler, smaller, and more efficient RF PA power systems without external bias regulators or digital control infrastructure.
Availability
LM3280TL/NOPB is available at Aetrix Electronics and suitable for cellular handset design, multi-band RF front-end development, and battery-powered portable radio production requiring stable component supply and long-term lifecycle support.
Supply support for LM3280TL/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 specializing in analog, embedded processing, and power management technologies with over 90 years of innovation in high-reliability electronics.
The LM3280TL/NOPB belongs to TI's RF Power Management Unit product line, designed specifically to optimize efficiency, size, and sequencing control for linear RF power amplifiers in battery-constrained mobile devices.
FAQ
What is the function of the VCON pin on the LM3280TL/NOPB?
The VCON pin on the LM3280TL/NOPB is an analog input that directly controls the buck converter output voltage according to VOUT = 3 × VCON. With VCON ranging from 0.267V to 1.200V, it enables precise, resistor-free programming of VOUT from 0.8V to 3.6V - critical for dynamic PA voltage scaling in cellular handsets. The LM3280TL/NOPB datasheet specifies ±2% output accuracy at 3.6V and 15pF input capacitance.
How does the LM3280TL/NOPB handle thermal protection?
The LM3280TL/NOPB incorporates thermal shutdown that activates at TJ = 150°C (typ.) and releases at TJ ≈ 125°C (25°C hysteresis), preventing permanent damage during overload or poor heatsinking. This protection is independent of current limiting and remains active until junction temperature falls below the release threshold. The LM3280TL/NOPB DSBGA package has a θJA of 48°C/W on a 4-layer board, supporting safe operation up to 125°C ambient with appropriate layout.
Can the LDOs on the LM3280TL/NOPB operate without the buck converter enabled?
No - the LDOs on the LM3280TL/NOPB require ENBUCK to be high before any ENLDOx signal takes effect. If ENBUCK is low, asserting ENLDO1/2/3 has no impact; the LDO outputs remain disabled and actively discharged. This interlock prevents LDO operation without a valid buck output, ensuring proper power sequencing for RF PAs. The LM3280TL/NOPB functional block diagram confirms LDO control logic is gated by the main buck enable path.
What is the difference between forced and automatic bypass mode on the LM3280TL/NOPB?
Forced bypass mode is activated by driving the BYP pin low (<0.4V), immediately connecting BYPOUT to PVIN through the internal bypass FET. Automatic bypass mode triggers when SVIN − VOUT falls below VBYPASS− (160–320mV) for longer than TBYP (10–20µs), and exits when the difference exceeds VBYPASS+ (350–540mV). Both modes deliver up to 500mA with <120mΩ RDS(ON), but automatic mode enables seamless, condition-based transitions without MCU intervention - a key feature of the LM3280TL/NOPB.
Does the LM3280TL/NOPB support simultaneous operation of all three LDOs?
Yes - the LM3280TL/NOPB supports concurrent operation of LDO1, LDO2, and LDO3, each independently enabled via ENLDO1, ENLDO2, and ENLDO3. All three deliver 2.85V ±1% at up to 20mA each, with fast turn-on (50–100µs) and 55dB PSRR at 1kHz. Their outputs share SGND but are electrically isolated, making the LM3280TL/NOPB ideal for multi-band RF front-ends requiring separate, noise-immune bias rails.
LM3280TL/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 16-WFBGA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Topology:
- Step-Down (Buck) (1), Linear (LDO) (3)
- Number of Outputs:
- 4
- Frequency - Switching:
- 2MHz
- Voltage/Current - Output 1:
- 0.8V ~ 3.6V, 300mA
- Voltage/Current - Output 2:
- 2.85V, 20mA
- Voltage/Current - Output 3:
- 2.85V, 20mA
- w/LED Driver:
- No
- w/Supervisor:
- No
- w/Sequencer:
- No
- Voltage - Supply:
- 2.7V ~ 5.5V
- Operating Temperature:
- -30°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-DSBGA
LM3280TL/NOPB FAQ
1.How can I place an order for LM3280TL/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM3280TL/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 LM3280TL/NOPB reliable?
The price and inventory of LM3280TL/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM3280TL/NOPB is usually 5 days.
3.What payment methods are accepted for LM3280TL/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM3280TL/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM3280TL/NOPB?
LM3280TL/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM3280TL/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 LM3280TL/NOPB?
For technical support, including LM3280TL/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM3280TL/NOPB requirements.
6.How does Aetrix verify that LM3280TL/NOPB is sourced from the original manufacturer or authorized distributors?
All LM3280TL/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 LM3280TL/NOPB meets industry standards.
7.What is the process for return or replacement of LM3280TL/NOPB?
All LM3280TL/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM3280TL/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 LM3280TL/NOPB part is unused and in its original packaging.
Return procedure for LM3280TL/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM3280TL/NOPB Tags
-
TPS6521905RHBR
Texas Instruments
-
MIC3385YHL-TR
Microchip Technology
-
A4402ELPTR-T
Allegro MicroSystems
-
LM26480SQ-AA/NOPB
Texas Instruments
-
A4402KLPTR-T
Allegro MicroSystems
-
BD71847AMWV-E2
ROHM Semiconductor
-
ADP5040ACPZ-1-R7
Analog Devices Inc.
-
LT3048IDC#TRPBF
Analog Devices Inc.
-
ADP5037ACPZ-R7
Analog Devices Inc.
-
XRP7714ILB-F
MaxLinear, Inc.
-
LTC3260EDE#TRPBF
Analog Devices Inc.
-
LTC3260EMSE#PBF
Analog Devices Inc.
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…
