Step Down DC - DC Converter Power IC
MD1422N
Output
adjustable
Input Voltage range 8V to 40V
Maximum Output Current 3A
Built_in MOSFETs for main switch and synchronous rectification
Adjustable output from 2.5V to 12V with external resistors
High Efficiency typ. 95% (at:Vin=8V, Vout=5V, Iout=1A)
Feature
Synchronous
Rectification
Remote On/Off
Fixed Frequency 250kHz PWM Control
Over Current Protection
Under Voltage Lockout
Thermal Shut Down
Remote On / Off
Block Diagram
Vref
R/C
5
Vcc
Vboot
VB
VGH
VDD
28
6
8
25
23
18∼21
UVLO
START =7.2V
STOP =6.7V
Boot
Vref=6.5V
ON/OFF
Control
HighSide
Vref=VOUT+5.8V
100゜
C
Bandgap Reference
Vref=5.0V±5％
150゜
C
HighSide
Driver
High/Low
MOS OFF
TSD
VOUT
Error Amp
PWM Comp
−
11∼14
Dead Taim
Control
＋
＋
−
LowSide
Vref=6.5V
3V
1V
2.45V
Q
OSC
f＝250kHz
R
LowSide
Driver
＋
S
−
P.GND
CLM Vth=
0.1∼0.2V
32
30
1
amp-
ampOUT
S/S
16
2
4,26
3
OCL− OCL＋
9
GND
VGL
※ N/C : 7,10,15,17,22,24,29,31
Pin Assignment ( SSOP32)
Standard Connection Diagram
8
INPUT
8∼40V
25
OUTPUT
2.5∼12V
18∼21
11∼14
30
5
＋
32
1
28
4,26
16
ON
GND
3
30
4
5
6
7
8
9
10
11
12
13
29
28
27
26
25
24
23
22
21
20
14
19
15
18
16
17
amp−
N/C
ampOUT
N/C
Vref
VTS
GND
VB
N/C
VGH
N/C
VDD
VDD
VDD
VDD
N/C
GND
*Please consult with us when it is desired to make
output adjustable in a range over 5.3V.
U097−2
31
SHINDENGEN
＋
2
32
2
P □□□□□
MD1422N
1
MD1422N
3
6
S/S
OCL−
OCL＋
GND
R/C
Vcc
N/C
Vboot
VGL
N/C
VOUT
VOUT
VOUT
VOUT
N/C
P.GND
(See the marking specification for the indication on the device)
25
