IPC-SM-782A-表面贴装焊盘图形设计标准.pdf.pdf - 第112页

4.0 COMPONENT DIMENSIONS Figure 2 provides the component dimensions for TO 252 components. Component Identiﬁer LW 1 W 2 T 1 T 2 P 1 P 2 H min max min max min max min max min max basic basic max TS-003* 9.32 10.41 0.64 0.…

1.0 SCOPE

This subsection provides the component and land pattern

dimensions for TO 252 (small outline transistor) components.

Basic construction of the TO 252 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 pat-

tern dimensions.

2.0 APPLICABLE DOCUMENTS

See Section 8.0 for documents applicable to the subsections.

2.1 Electronic Industries Association (EIA) JEDEC Pub-

lication 95 Registered and Standard Outlines for Solid State

and Related Products, TO-252, Issue ‘‘B’’ dated 9/88

Application for copies should be addressed to:

Global Engineering Documents

1990 M Street N.W.

Washington, DC

3.0 COMPONENT DESCRIPTIONS

These parts are for dual diodes and Darlington transistors.

3.1 Basic Construction See Figure 1.

3.1.1 Termination Materials Leads should 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.

Solder finish applied over precious metal electrodes should

have a diffusion barrier layer between the electrode metalliza-

tion and the solder finish. The barrier layer should be nickel or

an equivalent diffusion barrier, and should be at least 0.00125

mm [0.00005 in] thick.

3.1.2 Marking Parts are available with or without marked

values.

3.1.3 Carrier Package Format Carrier package format

shall be according to the following: body type TO-252, 12 mm

tape/8 mm pitch.

3.1.4 Resistance to Soldering Parts should be capable of

withstanding five cycles through a relow system operating at

215°C. Each cycle shall consist of 60 seconds exposure at

215°C. Parts must also be capable of withstanding a mini-

mum of 10 seconds immersion in molten solder at 260°C.

IPC-782-8-11-1

Figure 1 TO 252 construction

IPC-SM-782

Surface Mount Design

and Land Pattern Standard

Date

5/96

Section

8.11

Revision

Subject

TO 252/TO 268

Page1of4

4.0 COMPONENT DIMENSIONS

Figure 2 provides the component dimensions for TO 252 components.

Component

Identiﬁer

LW1W2T1T2P1P2H

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

TS-003* 9.32 10.41 0.64 0.91 4.35 5.35 0.51 0.80 4.00 5.50 2.28 4.57 2.38

TS-005** 14.60 15.88 0.51 0.91 6.22 6.86 2.29 2.79 8.00 9.00 2.54 5.08 4.83

TO 368 18.70 19.10 1.15 1.45 13.30 13.60 2.40 2.70 12.40 12.70 5.45 10.90 5.10

Figure 2 TO 252 component dimensions

*Formerly TO 252

**Formerly TO 263

6.35–6.73

▼

4.32

MIN

▼

5.97–6.22

2.55–2.93

▼

4.32

MIN

▼

IPC-782-8-11-2

IPC-SM-782

Subject

TO 252/TO 268

Date

5/96

Section

8.11

Revision

Page2of4

5.0 LAND PATTERN DIMENSIONS

Figure 3 provides the land pattern dimensions for TO 252

components. These numbers represent industry consensus

on the best dimensions based on empirical knowledge of fab-

ricated 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) Y1 (mm) Y2 (mm) X1 (mm) X2 (mm)

C (mm)

Placement Grid

(No. of Grid

Elements)

ref

235A TS-003* 11.20 1.60 6.20 1.00 5.40 7.30 24x16

236 TS-005** 16.60 3.40 9.60 1.00 6.80 10.10 36x24

237 TO 268 19.80 3.40 13.40 1.40 13.60 11.40 42x34

Figure 3 TO 252 land pattern dimensions

▼

Grid

placement

courtyard

▼

Dimensions are in millimeters

▼

IPC-782-8-11-3

IPC-SM-782

Subject

TO 252/TO 268

Date

5/96

Section

8.11

Revision

Page3of4