Max1870a step-up/step-down li+ battery charger, Typical operating characteristics – Rainbow Electronics MAX1870A User Manual
Page 9
MAX1870A
Step-Up/Step-Down
Li+ Battery Charger
_______________________________________________________________________________________
9
BATTERY INSERTION AND REMOVAL
MAX1870Atoc01
V
BATT
18V
16V
I
CHARGE
5A/div
0
CCI AND CCV
CCI
CCV
0
2V
4V
20V
2.00ms/div
BATTERY REMOVAL
BATTERY
INSERTION
CCV
CCI
BATTERY-REMOVAL RESPONSE
MAX1870Atoc02
V
BATT
21V
18V
20V
19V
16V
17V
10.0µs/div
R
CV
= 10kΩ, C
OUT
= 22µF
R
CV
= 10kΩ, C
OUT
= 44µF
R
CV
= 20kΩ, C
OUT
= 44µF
SYSTEM LOAD-TRANSIENT RESPONSE
MAX1870Atoc03
4A
2A
0A
INDUCTOR CURRENT
SYSTEM LOAD
INPUT CURRENT
BATTERY CURRENT
5A
0A
2A
0A
0A
5A
200µs
STEP-DOWN MODE
SYSTEM LOAD-TRANSIENT RESPONSE
MAX1870Atoc04
4A
2A
0A
INDUCTOR CURRENT
SYSTEM LOAD
INPUT CURRENT
BATTERY CURRENT
5A
0A
2A
0A
0A
5A
100µs
HYBRID MODE
CHARGE-CURRENT STEP RESPONSE
MAX1870Atoc05
2A
0A
1V
INDUCTOR CURRENT
BATTERY CURRENT
0V
CCI
0A
2A
0V
5V
V
ICTL
400µs
STEP-DOWN
MODE
CHARGE-CURRENT STEP RESPONSE
MAX1870Atoc06
2A
0A
1V
INDUCTOR CURRENT
BATTERY CURRENT
0V
CCI
0A
2A
0V
5V
V
ICTL
400µs
HYBRID MODE
Typical Operating Characteristics
(Circuit of Figure 1, V
DCIN
= 16V, CELLS = REFIN, V
CLS =
V
REF
, V
ICTL
= V
REFIN
= 3.3V, T
A
= +25°C, unless otherwise noted.)