Global Mixed-mode Technology Inc.
Layout Guide
An input capacitance of
≅
1
µ
F is required between the
G923 input pin and ground (the amount of the capaci-
tance may be increased without limit), This capacitor
must be located a distance of not more than 1cm from
the input and return to a clean analog ground.
G923
Input capacitor can filter out the input voltage spike
caused by the surge current due to the inductive effect
of the package pin and the printed circuit board’s rout-
ing wire. Otherwise, the actual voltage at the IN pin
may exceed the absolute maximum rating.
SOT-23-5
The output capacitor also must be located a distance
of not more than 1cm from output to a clean analog
ground. Because it can filter out the output spike
caused by the surge current due to the inductive effect
of the package pin and the printed circuit board
’
s rout-
ing wire. Figure 6 is adjustable mode of G923 PCB
layout. Figure 7 is a PCB layout of G923 fixed mode.
Figure 3. Recommended Minimum Footprint
Safe Operating Area of G923
[Power Dissipation Limit]
200
Maximum Recommended Output Current
Maximum Power Dissipation of SOT-23-5
0.7
Still Air
1oz Copper on SOT-23-5 Package
Mounted on recommend mimimum footprint (Rθ
J A
=240
°
C/W)
T
A
=25
°
C
0.6
0.5
Power Dissipation (W)
0.4
0.3
0.2
0.1
0
Output Current (mA)
150
100
T
A
=85
°
C
T
A
=55
°
C
50
TA=25
o
C,Still Air
1oz Copper on SOT-23-5 Package
Mounted on recommended mimimum footprint (R
θ
J A
=240
°
C/W)
0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Note: V
IN(max)
<= 5.5V
Input-Output Voltage Differential V
IN
-V
OUT
(V)
25
35
45
55
65
75
85
95 105 115 125
Amibent Temperature T
A
(
°
C)
Figure 4. Safe Operating Area
Figure 5. Power Dissipation vs. Temperature
*Distance betw een pin & capacitor must no more than 1cm
*Distance betw een pin & capacitor must no more than 1cm
Figure 6. Adjustable Mode
Figure 7. Fixed Mode
Ver: 1.5
Jan 16, 2007
TEL: 886-3-5788833
http://www.gmt.com.tw
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