LTC6946

30

6946fb

Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings.

package DescripTion

UFD Package

28-Lead Plastic QFN (4mm × 5mm)

(Reference LTC DWG # 05-08-1712 Rev B)

4.00

± 0.10

(2 SIDES)

2.50 REF

5.00

± 0.10

(2 SIDES)

NOTE:

1. DRAWING PROPOSED TO BE MADE A JEDEC PACKAGE OUTLINE MO-220 VARIATION (WXXX-X).

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

PIN 1

TOP MARK

(NOTE 6)

0.40

± 0.10

27

28

1

2

BOTTOM VIEW—EXPOSED PAD

3.50 REF

0.75

± 0.05

R = 0.115

TYP

R = 0.05

TYP

PIN 1 NOTCH

R = 0.20 OR 0.35

× 45° CHAMFER

0.25

± 0.05

0.50 BSC

0.200 REF

0.00 – 0.05

(UFD28) QFN 0506 REV B

RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS

APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED

0.70

±0.05

0.25

±0.05

0.50 BSC

2.50 REF

3.50 REF

4.10

± 0.05

5.50

± 0.05

2.65

± 0.05

3.10

± 0.05

4.50

± 0.05

PACKAGE OUTLINE

2.65

± 0.10

3.65

± 0.10

3.65

± 0.05