AS1343 austriamicrosystems AG, AS1343 Datasheet - Page 14

• Manufacturer Part Number: AS1343
• Description: DC-DC Boost Converter
• Manufacturer: austriamicrosystems AG

AS1343
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
Diode Selection
A Schottky diode must be used to carry the output current into the Cout and load during the NMOS switch-off time.
Note: Do not use ordinary rectifier diodes, since the slow recovery times will compromise efficiency.
The MBR0520 is a good choice because of the very low forward voltage and the extremly fast switching. If the output
voltage exceeds 20V the use of the PMEG4005 or the MBR0540 (40V Schottky diodes) is recommended. These
diodes are designed to handle an average forward current of 500mA. In applications with higher loads, the PMEG4010
or the MBRM140 should be used, due to the rated average forward current of 1A.
Table 7. Recommended Diodes
Figure 32. Efficiency Comparison of different Diodes;
www.austriamicrosystems.com
90
80
70
60
50
40
30
20
10
0
0.1
Part Number
PMEG4005
PMEG4010
MBRM140
MBR0540
MBR0520
V
IN
= 3V, V
Output Current (mA)
1
OUT
= 18V, L
Reverse Voltage
1
40V
20V
40V
40V
40V
10
= 6.8µH
PMEG4010
MBR0540
MBR0520
PMEG4005
Forward Current
100
Revision 1.04
0.5A
0.5A
0.5A
1A
1A
Figure 33. Efficiency Comparison of different Diodes;
90
80
70
60
50
40
30
20
10
0
0.1
V
IN
= 3.6V, V
Package
SOD123
SOD123
SOD123
SOD123
SOD123
Output Current (mA)
1
OUT
= 18V, L
MCC
www.mccsemi.com
Philips
www.nxp.com
ON Semiconductor
www.onsemi.com
10
1
= 6.8µH
www.DataSheet4U.com
Manufacturer
PMEG4010
MBR0540
MBR0520
PMEG4005
100
14 - 17