IPC-SM-782A-表面贴装焊盘图形设计标准.pdf.pdf - 第168页

4.0 COMPONENT DIMENSIONS Figure 2 provides the component dimensions for CQFP components. Component Identiﬁer L (mm) S (mm) W (mm) T (mm) A (mm) B (mm) H (mm) P (mm) min max min max min max min max min max min max max bas…

1.0 SCOPE

This subsection provides the component and land pattern

dimensions for ceramic quad flat pack (CQFP) components.

Basic construction of the CQFP device is also covered. At the

end of this subsection is a listing of the tolerances and target

solder joint dimensions used to arrive at the land pattern

dimensions.

2.0 APPLICABLE DOCUMENTS

JEDEC Publication 95

Registered and Standard Outlines for

Solid JEDEC Publication 95 State and Related Products, Out-

line MS 044

3.0 COMPONENT DESCRIPTIONS

3.1 Basic Construction

See Figure 1. Leaded ceramic

chip carriers are typically supplied with an open cavity for chip

placement. Ceramic or metal lids are soldered, epoxied, or

attached with glass frit around the cavity to provide a hermetic

seal.

An exception to this construction is the JEDEC standard

MS044, which has the chip bonded to a lead frame, which is

then sealed between two ceramic bodies with glass frit, simi-

lar to CERDIP fabrication. The ceramic packages are available

in 28- through 196-lead configurations, with 1.27, 0.80, and

0.64 mm center spacing.

Pre-leaded ceramic chip carriers typically have copper alloy or

Kovar leads that are attached by the manufacturer. Leads are

typically bonded to metallization on the top surface of the chip

carrier. However, leads can be attached to the package cas-

tellations as well. Brazing or thermocompression bonding is

usually the attachment means.

Pre-leaded packages using lead-frame construction are also

available. These chip carriers have ceramic bodies with two

opposing halves which mate above and below a lead frame to

which the chip has been previously bonded. The seal is pre-

formed with glass frit.

Leads can be formed to different shapes, such as ‘‘J,’’ ‘‘L,’’

or ‘‘C’’ configurations. Leads bent in the ‘‘L’’ configuration are

known as ‘‘gullwings.’’

Pre-leaded chip carriers may be supplied with leads straight

and attached to a common strip. The user must detach the

common strip and form the leads to the desired configuration.

This is done to minimize lead bending during shipping and

handling. Leads may be supplied pre-tinned or with gold plat-

ing, as is often done for packages intended for a high reliabil-

ity user.

3.1.1 Termination Materials Leads must be solder-

coated with a tin/lead alloy. The solder should contain

between 58 to 68% tin. Solder may be applied to the leads by

hot dipping or by plating from solution. Plated solder termina-

tions should be subjected to post-plating reflow operation to

fuse the solder. The tin/lead finish should be at least 0.0075

mm [0.0003 in] thick.

3.1.2 Marking All parts shall be marked with a part number

and ‘‘Pin 1’’ location. Pin 1 location may be molded into the

plastic body.

3.1.3 Carrier Package Format Tube carriers are preferred

for best handling.

3.1.4 Process Considerations CQFPs are usually pro-

cessed using standard solder reflow processes. Parts should

be capable of withstanding ten cycles through a standard

reflow system operating at 215°C. Each cycle shall consist of

60 seconds exposure at 215°C.

IPC-782-11-4-1

CQFP construction

IPC-SM-782

Surface Mount Design

and Land Pattern Standard

Date

5/96

Section

11.4

Revision

Subject

CQFP

Page1of4

4.0 COMPONENT DIMENSIONS

Figure 2 provides the component dimensions for CQFP components.

Component

Identiﬁer

L (mm) S (mm) W (mm) T (mm) A (mm) B (mm)

(mm)

min max min max min max min max min max min max max basic

CQFP-28 14.40 14.80 11.86 12.39 0.32 0.48 1.02 1.27 9.05 10.05 9.05 10.05 2.30 1.270

CQFP-36 17.15 17.39 14.61 15.04 0.20 0.33 1.02 1.27 11.69 12.70 11.69 12.70 4.92 1.270

CQFP-44 19.69 19.93 17.15 17.58 0.20 0.33 1.02 1.27 14.23 15.24 14.23 15.24 4.92 1.270

CQFP-52 22.23 22.47 19.69 20.12 0.20 0.33 1.02 1.27 16.77 17.78 16.77 17.78 4.92 1.270

CQFP-68 27.31 27.55 24.77 25.20 0.20 0.33 1.02 1.27 21.85 22.86 21.85 22.86 4.92 1.270

CQFP-84 32.39 32.63 29.85 30.28 0.20 0.33 1.02 1.27 26.93 27.94 26.93 27.94 4.92 1.270

CQFP-100 37.47 37.71 34.93 35.36 0.20 0.33 1.02 1.27 32.01 33.02 32.01 33.02 4.92 1.270

CQFP-120 30.95 31.45 28.75 29.50 0.30 0.46 0.70 1.10 26.80 27.30 26.80 27.30 4.06 0.800

CQFP-128 30.95 31.45 28.75 29.50 0.30 0.46 0.70 1.10 26.80 27.30 26.80 27.30 4.06 0.800

CQFP-132 27.28 27.58 25.08 25.72 0.15 0.38 0.70 1.10 23.75 24.38 23.75 24.38 3.55 0.635

CQFP-144 30.95 31.45 28.75 29.50 0.30 0.46 0.70 1.10 26.80 27.30 26.80 27.30 4.06 0.800

CQFP-148 33.50 34.00 30.96 31.57 0.12 0.25 1.02 1.27 28.21 28.71 28.21 28.71 3.10 0.635

CQFP-160 30.95 31.45 28.75 29.50 0.30 0.46 0.70 1.10 26.80 27.30 26.80 27.30 4.06 0.800

CQFP-164 33.50 34.00 30.96 31.57 0.12 0.25 1.02 1.27 28.80 29.30 28.80 29.30 3.35 0.635

CQFP-196 35.75 36.25 33.21 33.82 0.12 0.25 1.02 1.27 33.80 34.30 33.80 34.30 3.45 0.635

Figure 2 CQFP component dimensions

Pin #1

indicator

[1]

▼

Before trim & form

Pin #1

indicator

▼

After trim & form

▼

2.5

MIN

0.25

MIN

Lead form detail

The industry standard for the ceramic quad flat pack device family is not well defined.

The above details represent several configurations considered common but other sizes are available

▼

IPC-782-11-4-2

IPC-SM-782

Subject

CQFP

Date

5/96

Section

11.4

Revision

Page2of4

5.0 LAND PATTERN DIMENSIONS

Figure 3 provides the land pattern dimensions for CQFP com-

ponents. These numbers represent industry consensus on the

best dimensions based on empirical knowledge of fabricated

land patterns.

In the table, the dimensions shown are at maximum material

condition (MMC). The least material condition (LMC) should

not exceed the fabrication (F) allowance shown on page 4.

The LMC and the MMC provide the limits for each dimension.

The dotted line in Figure 3 shows the grid placement court-

yard which is the area required to place land patterns and

their respective components in adjacent proximity without

interference or shorting. Numbers in the table represent the

number of grid elements (each element is 0.5 by 0.5 mm) in

accordance with the international grid detailed in IEC publica-

tion 97.

RLP No.

Component

Identiﬁer Z (mm) G (mm) X (mm)

Y (mm) C (mm) D (mm) E (mm)

Placement Grid

(No. of Grid

Elements)ref ref ref ref

750A CQFP-28 15.80 10.60 0.65 2.60 13.20 7.62 1.27 34x34

751A CQFP-36 18.60 13.80 0.65 2.40 16.20 10.16 1.27 40x40

752A CQFP-44 21.00 16.20 0.65 2.40 18.60 12.70 1.27 44x44

753A CQFP-52 23.60 18.80 0.65 2.40 21.20 15.24 1.27 50x50

754A CQFP-68 28.60 23.80 0.65 2.40 26.20 20.32 1.27 62x62

755A CQFP-84 33.80 29.00 0.65 2.40 31.40 25.40 1.27 70x70

756A CQFP-100 38.80 34.00 0.65 2.40 36.40 30.48 1.27 80x80

757A CQFP-120 32.40 28.00 0.50 2.20 30.20 23.20 0.80 68x68

758A CQFP-128 32.40 28.00 0.50 2.20 30.20 24.80 0.80 68x68

759A CQFP-132 28.60 24.20 0.40 2.20 26.40 20.32 0.64 60x60

760A CQFP-144 32.40 28.00 0.50 2.20 30.20 24.80 0.80 68x68

761A CQFP-148 35.20 30.00 0.35 2.60 32.60 22.86 0.64 72x72

762A CQFP-160 32.40 28.00 0.50 2.20 30.20 24.80 0.80 68x68

763A CQFP-164 35.20 30.00 0.35 2.60 32.60 25.40 0.64 72x72

764A CQFP-196 37.20 32.00 0.35 2.60 34.60 30.48 0.64 76x76

Figure 3 CQFP land pattern dimensions

IPC-782-11-4-3

IPC-SM-782

Subject

CQFP

Date

5/96

Section

11.4

Revision

Page3of4