LM3668SD-4550/NOPB Texas Instruments Integrated Circuit (Small Outline No-lead) In Stock
LM3668SD-4550/NOPB is a high-efficiency dual-mode single-inductor buck-boost DC/DC converter delivering up to 1 A output with an input range of 2.5 V to 5.5 V. Using PWM voltage-mode control in a 12-pin SON package, it maintains regulation across input voltages above and below the output. Available from stock with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Small Outline No-lead
- Pin Count
- 13
- Lifecycle
- NOT RECOMMENDED
- Datasheet
- LM3668SD-4550/NOPB Datasheet PDF
- Category
- Integrated Circuit
- Temp Range
- -40.0°C to 85.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Single-inductor buck-boost topology delivers up to 1 A output current with input range 2.5 V to 5.5 V, maintaining regulation when Vin crosses Vout
- Dual-mode PWM voltage-mode control maximizes efficiency across light and heavy load conditions in battery-powered portable devices
- Compact 12-pin SON package minimizes board area for space-constrained wearable and IoT designs requiring stable power from Li-Ion cells
Applications
The LM3668SD-4550/NOPB is ideal for battery-powered portable electronics such as smartphones, tablets, and wearables where the supply voltage from a single Li-Ion cell (2.7 V to 4.2 V) must be regulated to a fixed output voltage of 4.55 V across the full discharge cycle. Its single-inductor buck-boost architecture reduces BOM cost and PCB area compared to separate buck and boost converter solutions. The device is also well-suited for USB-powered applications and portable medical devices requiring stable output voltage despite wide input voltage variation.
Specifications
| Pbfree Code | Yes |
| YTEOL | 3.9 |
| Analog IC - Other Type | DUAL SWITCHING CONTROLLER |
| Control Mode | VOLTAGE-MODE |
| Control Technique | PULSE WIDTH MODULATION |
| Input Voltage-Max | 5.5V |
| Input Voltage-Min | 2.5V |
| Input Voltage-Nom | 3.6V |
| JESD-30 Code | S-PDSO-N12 |
| JESD-609 Code | e3 |
| Number of Functions | 1 |
| Output Current-Max | 2.05A |
| Output Voltage-Max | 5V |
| Output Voltage-Min | 2.8V |
| Output Voltage-Nom | 4.5V |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SOLCC12,.12,16 |
| Package Shape | SQUARE |
| Package Style | SMALL OUTLINE, HEAT SINK/SLUG, VERY THIN PROFILE |
| Peak Reflow Temperature (Cel) | 260 |
| Qualification Status | Not Qualified |
| Surface Mount | YES |
| Switcher Configuration | BUCK-BOOST |
| Switching Frequency-Max | 2500kHz |
| Technology | CMOS |
| Temperature Grade | INDUSTRIAL |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | NO LEAD |
| Terminal Pitch | 0.4mm |
| Terminal Position | DUAL |
| Time@Peak Reflow Temperature-Max (s) | 30 |
| Package | Small Outline No-lead |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.90 |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What is the input voltage range of the LM3668SD-4550/NOPB and which battery chemistries does it support?
The LM3668SD-4550/NOPB accepts input voltages from 2.5 V to 5.5 V, covering the full discharge range of single-cell Li-Ion batteries (2.7 V to 4.2 V) and single-cell LiFePO4 batteries (2.5 V to 3.6 V). This makes it suitable for portable devices that must maintain a regulated 4.55 V output from a battery whose voltage crosses above and below the target output during normal use.
Why use a single-inductor buck-boost topology instead of separate buck and boost converters?
The LM3668SD-4550/NOPB uses a single inductor shared between buck and boost modes, reducing total component count by eliminating a second inductor, saving approximately 30% board area compared to a two-stage approach. This simplification also reduces power losses at mode transitions and lowers BOM cost in high-volume portable device production.
What output current can the LM3668SD-4550/NOPB deliver, and at what efficiency?
The LM3668SD-4550/NOPB delivers up to 1 A continuous output current with peak efficiency exceeding 90% under typical load conditions from a 3.6 V nominal input to the 4.55 V output. Its dual-mode PWM voltage-mode control transitions seamlessly between buck and boost modes, maintaining high efficiency across the load range from 10 mA to 1000 mA.
What package does the LM3668SD-4550/NOPB use and what does this mean for PCB layout requirements?
The LM3668SD-4550/NOPB is housed in a 12-pin SON (small outline no-lead) package measuring approximately 3 mm × 3 mm with an exposed thermal pad. The exposed pad must be soldered to a ground plane with at least 4 thermal vias to minimize junction-to-board thermal resistance, enabling sustained 1 A operation within a PCB footprint smaller than 25 mm².
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Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.
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