Datasheet

9Maxim Integrated
1.2A Switch-Mode Li+ Chargers with ±22V Input
Rating and JEITA Battery Temperature Monitoring
MAX8900A/MAX8900B/MAX8900C
Typical Operating Characteristics (continued)
(Circuit of Figure 1, V
IN
= 6V, V
BAT
= 3.6V, T
A
= +25NC, unless otherwise noted.)
SWITCHING FREQUENCY
vs. INPUT VOLTAGE
MAX8900A toc10
INPUT VOLTAGE (V)
SWITCHING FREQUENCY (MHz)
242016128
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0
42
8
V
BAT
= 4V
V
BAT
= 3V
MAX8900x
V
IN
RISING
V
OVLO
= 28V
V
CEN
= 0V
R
ISET
= 2.87kI
SWITCHING FREQUENCY
vs. CHARGE CURRENT
MAX8900A toc11
CHARGE CURRENT (A)
SWITCHING FREQUENCY (MHz)
1.00.80.60.40.2
1
2
3
4
5
6
0
0 1.2
V
IN
= 5V, V
BAT
= 3V
V
IN
= 6V, V
BAT
= 4V
V
IN
= 4.5V, V
BAT
= 4V
MAX8900B DC SWITCHING
WAVEFORMS (I
BAT
= 100mA)
MAX8900A toc12
5V/div
0V
0A
20mV/div
200mA/div
I
LX
V
LX
V
OUT
200ns/div
MAX8900B DC SWITCHING
WAVEFORMS (I
BAT
= 440mA)
MAX8900A toc13
5V/div
0V
0A
20mV/div
500mA/div
I
LX
V
LX
V
OUT
200ns/div
MAX8900B DC SWITCHING
WAVEFORMS (I
BAT
= 1.2A)
MAX8900A toc14
5V/div
0V
0A
20mV/div
500mA/div
I
LX
V
LX
V
OUT
200ns/div
MAX8900A toc15
T
A
(°C)
I
BAT
(A)
13511085603510-15
0.2
0.4
0.6
0.8
1.0
1.2
1.4
0
-40 185160
R
SETI
= 2.87kI
R
SETI
= 6.81kI
V
THM
= V
AVL
/2
CHARGE CURRENT
vs. AMBIENT TEMPERATURE