Unitek UNIBOND 2, User Manual

Page: 23 / 49

Figure 1 9 - Gold p l a t e d Kovar r i b b o n welded t o a n u n -
plated, 1 o z copper t r a c e f o r 4 ms i n t h e Vo l t a g e Mode.
I
VOLTAGE
flowi••••••••••14
VOLTAGE
-
-
-
i
.5
120
2
volts/cm
amps/cm
ms/cm
.
CURRENT
CURRENT
DURATION
VOLTAGE
P
VOLTAGE
CURRENT -
-
- .5 v o l t s / c m
120 amps/cm
2 ms/cm DURATION
i
CURRENT
l
.
I
VOLTAGE
.
1
1
I
VOLTAGE
CURRENT
DURATION - . 5
- 1 2 0
- 2 volts/cm
amps/cm
ms/cm
CURRENT
Figure 2 0 - Gold p l a t e d Rover r i b b o n welded t o a n unplated 1 o z copper t r a c e
for 4 ms i n t h e i n t h e Vo l t a g e + Current Feedback Mode u s i n g A m p l i t u d e and
Output Resistance s e t t i n g s o f ( a ) . 7 5 v and 3 . 6 m i l l i o h m s and ( b ) . 8 8 v o l t s
and
5 m i l l i o h m s .
5.15. T h e c u r r e n t peaked t o 160 amps d u r i n g t h e f i r s t 1 ms o f Figure 1 9 and 2 0 ( a ) .
I n t h e Constant Vo l t a g e Mode t h e c u r r e n t decreased l i n e a r l y t o 120 amps u n t i l m e l t i n g
occurred. I n t h e VOLTAGE + CURRENT MODE, t h e Unibond a u t o m a t i c a l l y increases t h e o u t -
put v o l t a g e a t t h e beginning o f t h e pulse u n t i l t h e e l e c t r o d e s s e a t themselves r e d u c -
ing t h e welding r e s i s t a n c e . T h e v o l t a g e continues t o change a s t h e r e s i s t a n c e between
the e l e c t r o d e s changes. M e l t i n g occurred d u r i n g t h e l a s t . 2 t o . 4 ms o f t h e welding
pulse a s i n d i c a t e d by t h e r i n g i n g i n both 2 0 ( a ) and ( b ) . T h e s e t t i n g s used i n t h e
Voltage + Current Mode a l l r e s u l t e d i n t h e Unibond m a i n t a i n i n g a constant v o l t a g e - c u r -
rent product o f 105 w a t t s ( . 7 5 v o l t s x 145 amps). I n c r e a s i n g t h e Output Resistance
- 1 8 -