MIC4682 Datasheet, PDF (14/15 Pages) Micrel Semiconductor – PRECISION CURRENT LIMIT SO-8 SUPERSWITCHER BUCK REGULATOR

MIC4682
Typical Application Circuits
Micrel
V_IN
11V to 24V
C1
10µF/25V
Taiyo Yuden
TMK432BJ106MM
GND
R1
10M
MIC4682
5
IN
8
SW
3
ISET
1
FB
R2
SHDN GND
28k
4
2,6,7
L1
47µH
Sumida
CDRH6D28-470NC
MIC79050
2
IN
3
BAT
R3
3.01k
R4
976Ω
C2
100µF
10V(x2)
1
EN
GND
AVX
5-8
TPSC107M010R0200
FB ⁴
D1
1A/40V
MBRX140
Micro Commercial Components
V_OUT
4.2V ±0.75%
C3
4.7µF/20V
AVX
TPSA475M020R1800
GND
MIC4682 Current Limit
Characteristics
4.5
4
3.5
3
V_IN = 12V
2.50
250 500 750 1000
OUTPUT CURRENT (mA)
Typical
Charging Characteristics
5
0.6
Constant Current
4.5
Constant Voltage
4
0.5
3.5
3
V_IN = 12V
Batt = 1.25Ah
0.4
2.5
Cutoff Voltage = 3.0V 0.3
2
1.5
0.2
1
0.1
0.5
00 _{1 2 3 4 5 6 7} 0
TIME (hrs)
Figure 6. Low-Cost Li Ion Battery Charger with 0.75% Precision Output Voltage
October 2003
14
M0334-102203