LM3561
www.ti.com SNOSB44C – MARCH 2011 – REVISED MAY 2013 Synchronous Boost Converter
With 600-mA High-Side LED Driver and I2C-Compatible Interface
Check for Samples: LM3561 FEATURES 1 2 High-Side Current Source Allows Grounded
LED Cathode
Up to 90% Efficient
Ultra-Small Solution Size: VIN) the inductor will typically be the biggest area of efficiency
loss in the circuit. Therefore, choosing an inductor with the lowest possible series resistance is important.
Additionally, the saturation rating of the inductor should be greater than the maximum operating peak current of
the LM3561. This prevents excess efficiency loss that can occur with inductors that operate in saturation. For
proper inductor operation and circuit performance ensure that the inductor saturation and the peak current limit
setting of the LM3561 is greater than IPEAK. This can be calculated by:
28 Submit Documentation Feedback Copyright © 2011–2013, Texas Instruments Incorporated Product Folder Links: LM3561 LM3561
www.ti.com IPEAK = SNOSB44C – MARCH 2011 – REVISED MAY 2013 I LOAD VOUT
V x (VOUT -VIN)
x
+ 'IL where 'IL = IN
K
VIN
2 x f SW x L x VOUT (3) Ж’SW = 2MHz, and О can be found in the Typical Performance Characteristics plots.
Table 15. Recommended Inductors
Manufacturer L Part Number Dimensions (L×W×H) RDC ISAT Coilcraft 1µH XPL2010-102ML 2mm×1.9mm×1mm 81mΩ 1.6A TDK 1µH VLS252012T-1R0N 2mm×2.5mm×1.2mm 73mΩ 2.7A TDK 1µH VLS2010-1R0N 2mm x 2mm x 1mm 90mΩ 1.65A TDK 1µH VLS2012ET-1R0N 2mm x 2mm x 1.2mm 71mΩ 1.65A TDK 1µH VLS20160ET-1R0N 2mm x 1.6mm x 0.95mm 100mΩ 1.5A TDK 1µH VLS252010ET-1R0N 2.5mm x 2mm x 1mm 70mΩ 1.9A NTC THERMISTOR SELECTION
Programming bit [4] of Configuration Register 1 with a (1) selects Thermal Comparator mode, making the …
