ltc3406ab-2 Linear Technology Corporation, ltc3406ab-2 Datasheet - Page 13

• Manufacturer Part Number: ltc3406ab-2
• Description: 2.25mhz, 600ma Synchronous Step-down Regulator In Thinsot
• Manufacturer: Linear Technology Corporation

For the feedback resistors, choose R1 = 309k. R2 can
then be calculated from Equation (2) to be:
Use a 976k 1% resistor.
APPLICATIONS INFORMATION
V
R
IN
2
=
⎛
⎝ ⎜
C
4.7µF
CER
V
IN
200mV/DIV
100mV/DIV
0 6
500mA/DIV
500mA/DIV
500mA/DIV
500mA/DIV
OUT
†
.
I
I
V
V
LOAD
LOAD
OUT
OUT
−
I
I
L
L
V
LTC3406AB-2
RUN
1 1 978
IN
V
V
I
Load Step
V
V
I
Load Step
LOAD
LOAD
⎞
⎠ ⎟
IN
OUT
IN
OUT
GND
R
= 3.6V
= 3.6V
= 2.5V
= 2.5V
= 0mA TO 600mA
= 100mA TO 600mA
V
SW
=
FB
Figure 5a
309k
k
2.2µH*
20µs/DIV
20µs/DIV
3406AB2 F05a
22pF
976k
** TAIYO YUDEN JMK316BJ106ML
* MURATA LQH32CN2R2M33
†
TAIYO YUDEN JMK212BJ475MG
3406AB2 TA02
3406AB2 TA04
C
10µF
CER
OUT
**
V
2.5V
600mA
OUT
Figure 5 shows the complete circuit along with its ef-
fi ciency curve.
100mV/DIV
500mA/DIV
500mA/DIV
100mV/DIV
500mA/DIV
500mA/DIV
Figure 5b. Effi ciency vs Load Current
I
V
LOAD
OUT
I
V
LOAD
100
OUT
I
90
80
70
60
50
40
30
20
10
L
0
I
L
V
V
I
0.1
LOAD
IN
OUT
Load Step
V
V
I
Load Step
V
LOAD
IN
OUT
= 3.6V
OUT
= 2.5V
= 3.6V
= 200mA TO 600mA
= 2.5V
= 2.5V
= 50mA TO 600mA
1
OUTPUT CURRENT (mA)
20µs/DIV
20µs/DIV
LTC3406AB-2
10
100
V
V
V
IN
IN
IN
3406AB2 TA05
3406AB2 F05b
3406AB2 TA03
= 2.7V
= 3.6V
= 4.2V
1000
13
3406ab2f