ADM8845
90
85
80
75
70
65
60
55
50
45
40
V
V
V
= 3.6V
= 4.0V
= 4.3V
F
F
F
1
V
CC
2
V
V
V
= 3.8V
= 3.2V
OUT
F
F
B
B
W
CH1 20.0mV
CH2 20.0mV
M 400ns CH1
220mV
W
2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2
V
CC
Figure 15. 1× Mode Operating Waveforms
Figure 18. Power Efficiency vs. Supply Voltage over Li-Ion Range,
Six LEDS @ 20 mA/LED
90
90
V
V
V
= 4.3V
= 4.0V
= 3.8V
V
V
V
= 3.8V
F
F
F
F
F
F
85
80
75
70
65
60
55
50
45
40
85
80
75
70
65
60
55
50
45
40
= 4.0V
= 4.3V
V
V
= 3.6V
= 3.2V
F
V
V
= 3.6V
= 3.2V
F
F
F
2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2
2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2
V
CC
V
CC
Figure 19. Power Efficiency vs. Supply Voltage over Li-Ion Range
Four LEDS @ 20 mA/LED
Figure 16. Power Efficiency vs. Supply Voltage over Li-ion Range,
Six LEDS @ 15 mA/LED
90
V
V
V
= 3.8V
= 4.0V
= 4.3V
F
F
F
C2 FALL
200µs
LOW SIGNAL
AMPLITUDE
85
80
75
70
65
60
55
50
45
40
∆: 44.0ms
@: –44.4ms
CTRL1/2
1
V
OUT
V
V
= 3.6V
= 3.2V
F
F
2
2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2
CH1 2.00V CH2 2.00V
M10.0ms
CH2
4.36V
V
CC
Figure 20. TPC Delay
Figure 17. Power Efficiency vs. Supply Voltage over Li-Ion Range,
Four LEDS @ 15 mA/LED
Rev. 0 | Page 8 of 20