LTC3355_15 Datasheet, PDF (18/20 Pages) Linear Technology – 20V 1A Buck DC/DC with Integrated SCAP Charger and Backup Regulator

LTC3355
PACKAGE DESCRIPTION
Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings.
UF Package
20-Lead Plastic QFN (4mm × 4mm)
(Reference LTC DWG # 05-08-1710 Rev A)
4.50 ±0.05
3.10 ±0.05
2.00 REF
2.45 ±0.05
2.45 ±0.05
0.70 ±0.05
PACKAGE OUTLINE
0.25 ±0.05
0.50 BSC
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED
4.00 ±0.10
0.75 ±0.05
R = 0.05
TYP
PIN 1
TOP MARK
(NOTE 6)
4.00 ±0.10
2.00 REF
BOTTOM VIEW—EXPOSED PAD
R = 0.115
TYP
19 20
PIN 1 NOTCH
R = 0.20 TYP
OR 0.35 × 45°
CHAMFER
0.40 ±0.10
1
2.45 ±0.10
2
2.45 ±0.10
0.200 REF
0.00 – 0.05
NOTE:
1. DRAWING IS PROPOSED TO BE MADE A JEDEC PACKAGE OUTLINE MO-220
VARIATION (WGGD-1)—TO BE APPROVED
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
ON THE TOP AND BOTTOM OF PACKAGE
(UF20) QFN 01-07 REV A
0.25 ±0.05
0.50 BSC
18
For more information www.linear.com/LTC3355
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