ELM605DA
2A synchronous step-down DC/DC converter
■Pin configuration
SOP-8(TOP VIEW)
Pin No.
Pin name
VCC
PG
GND
FB
EN
PGND
SW
Pin description
Supply voltage input
Power good
Ground
Feedback/Output voltage
Enable input
Power switch ground
Power switch output
Power switch supply voltage input
1
2
3
4
5
6
7
8
1
8
7
6
5
2
3
4
VIN
■Standard circuit
ELM605DA
Vin
PG
8
1
2
VIN
PG
10µF
100k 10
100k
22µF
2.2µH
Vout
7
4
VCC
SW
FB
0.1µF
Cup*
(option)
R1
R2
5
EN
PGND GND
6
3
Vout=0.8V*(1+R1/R2)
■Block diagram
VIN
VCC
EN
500k ohm
Slop comp
+
-
+
Current
sence
Reference
amplifier
M1
M2
PWM
logic
UG
LG
+
-
0.8V
+
-
FB
PWM
SW
Error
comparator
Clock
amplifier
Oscillator
PG
+
-
0.72V
-
DCC
+
PGND
Zero-current
comparator
GND
Rev.1.2
13 - 2
ELM-TECH [ ELM Technology Corporation ]
