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Texas Instruments LM27965SQX
- Part No.:
- LM27965SQX
- Manufacturer:
- Texas Instruments
- Category:
- LED Drivers
- Package:
- 24-WFQFN Exposed Pad
- Datasheet:
-
LM27965SQX.pdf
- Description:
- IC LED DRV RGLTR I2C 30MA 24WQFN
- Quantity:
- Payment:
- Shipping:
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Product details
Overview
LM27965SQX from Texas Instruments is a dual-display white LED driver IC with I²C-compatible brightness control, adaptive 1×/3/2× charge pump, 0.3% current matching across LED banks, 180mA total regulated output current, and operation from 2.7V to 5.5V input-designed for mobile phone main/sub display backlighting.
For engineers reviewing the LM27965SQX datasheet, LM27965SQX pinout, LM27965SQX application, or LM27965SQX equivalent, this page delivers verified technical context, real-world current regulation behavior, package-validated pin functions, and confirmed alternative options for multi-bank LED driver selection in space-constrained portable systems.
Technical Context
The LM27965SQX implements an adaptive CMOS charge pump that dynamically selects 1× (pass-through) or 3/2× gain based on forward voltage monitoring of active DxA/DxB pins-ensuring ≥91% peak efficiency without inductors. It integrates three independently controlled current-sink banks: BankA (5 pins), BankB (3 pins), and BankC (1 pin), each with distinct brightness control methods.
Current regulation relies on a resistor-programmed ISET reference (1.25V typical), delivering full-scale LED current via IDxx = 200 × (1.25 V / RSET). BankA/B support 32-step I²C-controlled PWM+analog dimming at 20 kHz; BankC offers 4-step analog-only control. RESET pin enables hardware disable independent of I²C bus state.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Total Output Current | 180 mA maximum-distributed across BankA (5×), BankB (3×), and BankC (1×) current sinks with per-pin limits up to 30 mA. |
| LED Current Matching | 0.3% typical-tight matching between sinks within BankA and BankB ensures uniform brightness across multi-LED displays. |
| Charge Pump Gain | Adaptive 1× or 3/2×-automatically selected based on real-time VLED sensing to maximize efficiency across input voltage (2.7–5.5 V) and load conditions. |
| Brightness Control | BankA/B: 32-level I²C register control (PWM + analog); BankC: 4-level analog only-enabling independent dimming of main, sub, and indicator LEDs. |
| Input Voltage Range | 2.7 V to 5.5 V-supports single-cell Li-ion battery operation with extended low-voltage headroom down to 2.7 V. |
| Headroom Requirement | 110 mV minimum at 15 mA-defines minimum (VPOUT – VLED) needed for stable current regulation across all banks. |
| Quiescent Current | 3.32 mA typical in 3/2× mode, no load-critical for standby power budgeting in always-on display subsystems. |
Pinout & Package
LM27965SQX is housed in a 24-pin WQFN package (4 mm × 4 mm × 0.8 mm, RTW0024A), with exposed thermal pad (DAP) connected to GND for enhanced thermal performance. Pin numbering follows standard top-view layout with pins 1–12 on top row, 13–24 on bottom row, and DAP centered underneath.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN (24) | Main power input | Supplies charge pump and internal circuitry; accepts 2.7–5.5 V with ±0.3 V absolute max rating. |
| POUT (23) | Charge pump output | Regulated high-side rail for all LED current sinks; voltage adapts between VIN (1×) and 1.5×VIN (3/2×). |
| SCL (1), SDIO (2) | I²C interface signals | Standard bidirectional I²C bus lines referenced to VIO; support 100 kHz/400 kHz modes with 2.5 µs min clock period. |
| VIO (7) | I²C logic level reference | Sets logic thresholds for SCL/SDIO; compatible with 1.4–VIN V range-enables interfacing with 1.8 V or 3.3 V controllers. |
| ISET (17) | Current reference input | Accepts external RSET to ground; sets full-scale LED current via IDxx = 200 × (1.25 V / RSET). |
| RESET (10) | Hardware reset input | Active-low asynchronous reset; pulls all registers to default and disables outputs when driven below 0.45 V. |
| D1A–D5A (12–16) | BankA LED current sinks | Five independently enabled constant-current outputs for main display LEDs; each supports ≤30 mA. |
| D1B–D3B (4–6) | BankB LED current sinks | Three constant-current outputs for sub-display LEDs; forward voltage sensing enables adaptive gain switching. |
| D1C (3) | Indicator LED sink | Single current sink for status/indicator lighting; 4-level analog dimming only-no VLED sensing. |
| GND (9, 18, DAP) | Ground reference | Three dedicated GND pins plus thermally enhanced DAP-required for stable regulation and thermal dissipation. |
| NC (8, 11) | No-connect | Unbonded pins-must be left floating or tied to GND per layout guidelines; no electrical function. |
Key Features
| Feature | Design Value |
|---|---|
| No-inductor architecture | Eliminates magnetic components and EMI concerns-reduces BOM count and PCB area by enabling capacitor-only charge-pump design. |
| 0.3% current matching | Ensures consistent luminance across all LEDs in BankA and BankB-critical for artifact-free display backlighting in handheld devices. |
| Resistor-programmable full-scale current | Enables precise LED current tuning (e.g., 15 mA, 20 mA, 25 mA) using a single external RSET-simplifies design iteration and production calibration. |
| I²C-compatible dual-address option | Supports 0x36 (LM27965SQX) and 0x38 (LM27965SQX-M) addresses-allows co-location of multiple drivers on same bus without address conflict. |
| 25 mm² total solution size | Includes IC, flying caps (C1/C2), input/output caps, and RSET-meets stringent footprint requirements for thin mobile form factors. |
Applications
| Mobile Phone Main Display Backlight | PDA Sub-Display Lighting |
|---|---|
Use Scenario: Driving 5 parallel white LEDs (3.6 VF, 20 mA each) for primary LCD backlight in compact smartphone. IC Role / Device Role / Timing Role: Constant-current sink bank (BankA) with adaptive 3/2× charge pump gain and I²C brightness control. Use Value: Delivers uniform brightness and >91% efficiency across 3.0–4.2 V Li-ion battery discharge curve without inductor. |
Use Scenario: Powering 3 smaller white LEDs (3.2 VF, 15 mA each) for secondary display in clamshell PDA. IC Role / Device Role / Timing Role: Independent current sink bank (BankB) with synchronized VLED sensing and separate 32-step dimming. Use Value: Enables simultaneous but independent dimming of main and sub displays-preserving UI hierarchy and battery life. |
| Indicator LED Driver | General-Purpose Multi-Bank LED Control |
Use Scenario: Driving single amber indicator LED (2.1 VF, 10 mA) for system status in wearable device. IC Role / Device Role / Timing Role: Dedicated BankC current sink with 4-level analog dimming and no VLED sensing overhead. Use Value: Provides simple, low-noise indicator control without consuming BankA/B resources or requiring I²C traffic. |
Use Scenario: Configuring mixed LED loads-e.g., 4× main display, 2× sub display, 1× indicator-with shared RSET and unified I²C bus. IC Role / Device Role / Timing Role: Single-chip triple-bank LED driver with programmable current scaling and independent enable/disable per bank. Use Value: Reduces component count vs. discrete drivers-simplifies layout, lowers assembly cost, and improves thermal coupling. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-bank white LED driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM3530UMX/NOPB | 4-channel I²C LED driver with ambient light sensor interface; fixed 1.8 V to 5.5 V input; no adaptive charge pump gain switching. | Requires external ALS for auto-brightness; lacks BankC indicator sink; supports only 30 mA total output (vs. 180 mA). | Select when ambient light adaptation is required and total LED current ≤30 mA-unsuitable for high-current dual-display use cases. |
| TPS61165DRVR | Single-bank 40 V boost converter LED driver; 1.8–6 V input; supports up to 40 V LED strings; no I²C interface-uses analog/PWM dimming only. | Cannot drive independent main/sub banks; requires external MOSFET and inductor; no integrated current matching or VLED sensing. | Select for high-VF LED strings (>5 V) where I²C control and multi-bank isolation are not needed. |
Compared with LM3530UMX/NOPB and TPS61165DRVR, LM27965SQX uniquely combines triple-bank independent control, adaptive gain charge pumping, 0.3% matching, and 180 mA capacity in a 4 mm × 4 mm WQFN-making it the only option for compact, high-efficiency dual-display backlighting with indicator support.
Availability
LM27965SQX is available at Aetrix Electronics and suitable for mobile phone display lighting, PDA backlighting, and general LED lighting applications requiring stable component supply, long-term lifecycle support, and traceable sourcing for production programs.
Supply support for LM27965SQX 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-delivering high-reliability, application-optimized ICs for industrial, automotive, and consumer markets.
The LM27965SQX belongs to TI's white LED driver product line, engineered specifically for space-constrained portable electronics requiring efficient, multi-bank, I²C-controllable backlight solutions with minimal external components.
FAQ
What is the maximum per-pin LED current supported by LM27965SQX?
The LM27965SQX supports up to 30 mA per DxA, DxB, or D1C pin under specified operating conditions. This limit applies individually to each current sink-BankA (D1A–D5A), BankB (D1B–D3B), and BankC (D1C)-and is validated across the full input voltage range (2.7–5.5 V) and temperature range (–30°C to +100°C). Exceeding 30 mA risks violating absolute maximum ratings and compromising current regulation stability.
How does the LM27965SQX select between 1× and 3/2× charge pump gain?
The LM27965SQX monitors forward voltage on active DxA and DxB pins in real time. When any enabled Dxx pin voltage (VPOUT – VLED) falls to approximately 175 mV, the device automatically switches from 1× (pass-through) to 3/2× gain mode to maintain current regulation headroom. BankC (D1C) is excluded from sensing-its operation remains unaffected by gain transitions.
Can LM27965SQX drive LEDs with different forward voltages across BankA and BankB?
Yes-the LM27965SQX supports mixed VF LEDs across BankA and BankB because its gain selection logic evaluates the highest forward voltage among *all active* DxA and DxB pins. For example, if BankA uses 3.6 V LEDs and BankB uses 3.2 V LEDs, the gain transition point is determined by the 3.6 V group, ensuring both banks remain properly regulated without manual configuration.
What is the function of the RSET resistor in LM27965SQX circuits?
The RSET resistor connected between ISET (pin 17) and GND sets the full-scale LED current for all banks via IDxx = 200 × (1.25 V / RSET). For instance, a 12.7 kΩ RSET yields ~19.7 mA nominal per sink. This resistor establishes the analog current reference-brightness control registers then scale this base current digitally via PWM (BankA/B) or analog attenuation (BankC).
Does LM27965SQX require external capacitors, and what values are recommended?
Yes-LM27965SQX requires four external ceramic capacitors: CIN (input, 1.0 µF), COUT (output, 1.0 µF), and two flying capacitors C1/C2 (1.0 µF each). TI specifies low-ESR MLCCs (e.g., TDK C1608X5R1A105K) for optimal charge pump efficiency and stability. Deviation from these values may degrade regulation accuracy, increase ripple, or trigger thermal shutdown under load.
LM27965SQX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 24-WFQFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- DC DC Regulator
- Topology:
- Switched Capacitor (Charge Pump)
- Internal Switch(s):
- Yes
- Number of Outputs:
- 9
- Voltage - Supply (Min):
- 2.7V
- Voltage - Supply (Max):
- 5.5V
- Voltage - Output:
- 2V ~ 4V
- Current - Output / Channel:
- 30mA
- Frequency:
- 1.27MHz
- Dimming:
- I2C
- Applications:
- Backlight
- Operating Temperature:
- -30°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 24-WQFN (4x4)
LM27965SQX FAQ
1.How can I place an order for LM27965SQX through Aetrix?
Please submit a Request for Quotation (RFQ) for LM27965SQX 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 LM27965SQX reliable?
The price and inventory of LM27965SQX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM27965SQX is usually 5 days.
3.What payment methods are accepted for LM27965SQX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM27965SQX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM27965SQX?
LM27965SQX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM27965SQX 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 LM27965SQX?
For technical support, including LM27965SQX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM27965SQX requirements.
6.How does Aetrix verify that LM27965SQX is sourced from the original manufacturer or authorized distributors?
All LM27965SQX 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 LM27965SQX meets industry standards.
7.What is the process for return or replacement of LM27965SQX?
All LM27965SQX units undergo pre-shipment inspection (PSI). If there is an issue with LM27965SQX, 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 LM27965SQX part is unused and in its original packaging.
Return procedure for LM27965SQX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM27965SQX Tags
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BCR402RE6327HTSA1
Infineon Technologies
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BCR430UXTSA2
Infineon Technologies
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BCR420UE6433HTMA1
Infineon Technologies
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BCR420UE6327HTSA1
Infineon Technologies
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BCR421UE6327HTSA1
Infineon Technologies
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LYT1604D-TL
Power Integrations
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HV9910CLG-G
Microchip Technology
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CL2N8-G
Microchip Technology
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BCR420UW6-7
Diodes Incorporated
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BCR421UW6-7
Diodes Incorporated
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BCR420UFD-7
Diodes Incorporated
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BCR421UFD-7
Diodes Incorporated
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