Typical operating characteristics (continued) – Rainbow Electronics MAX8621Z User Manual
Page 7
MAX8621Y/MAX8621Z
Dual Step-Down DC-DC Power-Management ICs
for Portable Devices
_______________________________________________________________________________________
7
Typical Operating Characteristics (continued)
(Circuit of Figure 3, V
IN1
= V
IN2
= V
IN3
= 3.6V, PWRON = IN, V
BUCK1
= 1.375V, V
BUCK2
= 1.8V, V
OUT1
= 2.6V, V
OUT2
= 2.6V, V
OUT3
= 1.8V, V
OUT4
= 3.0V, SEL1 = SEL2 = open, LX1 = LX2 = Murata LQH32CN2R2M53, T
A
= +25°C, unless otherwise noted.)
OUT1 OUPUT VOLTAGE
vs. INPUT VOLTAGE
MAX8621 toc05
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
5.0
4.5
4.0
3.5
3.0
2.525
2.550
2.575
2.600
2.625
2.650
2.500
2.5
5.5
LOAD = 0
LOAD = 300mA
FALLING
RISING
OUT2 OUTPUT VOLTAGE ACCURACY
vs. LOAD CURRENT
MAX8621 toc06
LOAD CURRENT (mA)
OUTPUT VOLTAGE ACCURACY (%)
250
200
50
100
150
-1.5
-1.0
-0.5
0
0.5
1.0
1.5
2.0
-2.0
0
300
OUT4 DROPOUT VOLTAGE
vs. LOAD CURRENT
MAX8621 toc07
LOAD CURRENT (mA)
DROPOUT VOLTAGE (mV)
100
50
20
40
60
80
100
120
140
160
0
0
150
OUT1 POWER-SUPPLY
RIPPLE REJECTION vs. FREQUENCY
MAX8621 toc08
FREQUENCY (kHz)
POWER-SUPPLY RIPPLE REJECTION (dB)
100
10
1
10
20
30
40
50
60
70
80
0
0.1
1000
EFFICICENCY vs. LOAD CURRENT
(V
BUCK2
= 1.8V)
MAX8621 toc09
LOAD CURRENT (mA)
EFFICIENCY (%)
100
10
1
50
60
70
80
90
100
40
0.1
1000
2.2
µH
4.7
µH
1
µH
BUCK1, OUT1, OUT2:
ON WITH NO LOAD
EFFICICENCY vs. LOAD CURRENT
(V
BUCK1
= 1.375V)
MAX8621 toc10
LOAD CURRENT (mA)
EFFICIENCY (%)
100
10
1
50
60
70
80
90
100
40
0.1
1000
2.2
µH
4.7
µH
1
µH
BUCK2, OUT1, OUT2:
ON WITH NO LOAD