UHH Package 56-Lead Plastic QFN (5mm × 9mm) (Reference LTC DWG # 05-08-1727 Rev B) 0.70 ±0.05 5.50 ±0.05 (2 SIDES) 4.10 ±0.05 (2 SIDES) 3.60 REF (2 SIDES) 3.45 ±0.05 7.13 ±0.05 PACKAGE OUTLINE 0.20 ±0.05 0.40 BSC 6.80 REF (2 SIDES) 8.10 ±0.05 (2 SIDES) 9.50 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 5.00 ±0.10 (2 SIDES) 0.75 ±0.05 PIN 1 NOTCH R = 0.30 TYP OR 0.35 × 45° CHAMFER 3.60 REF 55 56 0.00 – 0.05 0.40 ±0.10 PIN 1 TOP MARK (SEE NOTE 6) 1 2 9.00 ±0.10 (2 SIDES) 6.80 REF 7.13 ±0.10 3.45 ±0.10 (UHH) QFN 0515 REV B 0.200 REF 0.200 REF 0.00 – 0.05 0.75 ±0.05 NOTE: 1. DRAWING IS NOT A JEDEC PACKAGE OUTLINE 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 0.20 ±0.05 R = 0.10 TYP 0.40 BSC BOTTOM VIEW—EXPOSED PAD 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm 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