UCSP Reliability

The UCSP represents a unique packaging form factor

that may not perform equally to a packaged product

through traditional mechanical reliability tests. CSP relia-

bility is integrally linked to the user’s assembly methods,

circuit board material, and usage environment. The user

should closely review these areas when considering use

of a CSP package. Performance through Operating Life

Test and Moisture Resistance remains uncompromised

as it is primarily determined by the wafer-fabrication

process.

Mechanical stress performance is a greater considera-

tion for a CSP package. CSPs are attached through

direct solder contact to the user’s PC board, foregoing

the inherent stress relief of a packaged product lead

frame. Solder joint contact integrity must be consid-

ered. Table 5 shows the testing done to characterize

the CSP reliability performance. In conclusion, the

UCSP is capable of performing reliably through envi-

ronmental stresses as indicated by the results in the

table. Additional usage data and recommendations are

detailed in the UCSP application note, which can be

found on Maxim’s website at www.maxim-ic.com.

Chip Information

TRANSISTOR COUNT: 698

PROCESS TECHNOLOGY: CMOS

+2.5V to +5.5V RS-232 Transceivers

in UCSP

______________________________________________________________________________________

11

MAX3229

5k

Ω

R1IN

R1OUT

TTL/CMOS

C2-

C2+

C1-

C1+

A1

A5

C1

D1

A2

A3

A6

C6

B1

A4

E3

E5

E2

20

µA

20

µA

E1

C5

B5

V-

V+

2.5V TO 5.5V

C4

0.1

µF

C3

0.1

µF

C1

0.1

µF

C2

0.1

µF

0.1

µF

0.1

µF

FORCEOFF

FORCEON

INVALID

T1OUT

T1IN

GND

TO POWER-

MANAGEMENT

UNIT

RS-232

1.65V TO 5.5V

Typical Operating Circuits

(continued)

TEST

CONDITIONS

DURATION

NO. OF FAILURES PER

SAMPLE SIZE

Temperature Cycle

-35

°C to +85°C,

-40

°C to +100°C

150 cycles,

900 cycles

0/10,

0/200

Operating Life

°C

240hr

0/10

Moisture Resistance

+20

°C to +60°C, 90% RH

240hr

0/10

Low-Temperature Storage

-20

°C

240hr

0/10

Low-Temperature Operational

-10

°C

24hr

0/10

Solderability

8hr steam age

—

0/15

ESD

±2000V, Human Body Model

—

0/5

High-Temperature Operating

Life

168hr

0/45

Table 5. Reliability Test Data