Table 1. set truth table – Rainbow Electronics MAX8804Z User Manual
Page 9
DC/USB Mode and
Charging Current Setting
SET is a logic input that sets DC/USB charging mode
and charging current. Drive SET low or leave it uncon-
nected to enable DC charging mode. Drive SET high to
enable USB charging mode (see Table 1). SET can
also be driven by series pulses to program the charg-
ing current in both DC and USB mode.
DC Charge Mode
Drive SET low or leave it unconnected to enable DC
charging mode. Subsequent pulses on SET program the
charging current and the top-off threshold. There are
seven fast-charge current options and four top-off thresh-
old options. Default fast-charge current and top-off
threshold current are 500mA and 80mA. Pulse SET high
(1µs to 1ms pulse width) subsequently to realize charging
current and top-off threshold programming and transition.
After the 28th pulse, the MAX8804Y/MAX8804Z go into
the default mode and start a new cycle. See Table 2 and
Figure 3 to set the desired charging current and top-off
threshold. Drive SET high longer than 2ms to disable DC
charging-control circuitry.
MAX8804Y/MAX8804Z
High-Voltage, Dual-Input, USB/AC
Adapter Chargers in 2mm x 3mm TDFN
_______________________________________________________________________________________
9
Table 1. SET Truth Table
SET
V
DC
V
USB
CHARGER STATUS
0
Invalid
Invalid
Off
0
Invalid
Valid
Off
0
Valid
Invalid
DC charging mode enabled,
USB charging mode disabled
0
Valid
Valid
DC charging mode enabled,
USB charging mode disabled
1
Invalid
Invalid
Off
1
Invalid
Valid
DC charging mode disabled,
USB charging mode enabled
1
Valid
Invalid
Off
1
Valid
Valid
Off
Table 2. DC Charging Current Programming by Series Pulses
PULSE
NUMBER
DEFAULT
1st
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
11th
12th
13th
14th
I
CHG
(mA)
500
500
500
500
550
550
550
550
600
600
600
600
450
450
450
Top - O ff C ur r ent
Thr eshol d ( m A)
80
90
100
70
80
90
100
70
80
90
100
70
80
90
100
PULSE
NUMBER
—
15th
16th
17th
18th
19th
20th
21st
2 2 n d 2
3 r d 24th
25th
26th
27th
28th
I
CHG
(mA)
—
450
400
400
400
400
650
650
650
650
700
700
700
700
500
Top - O ff C ur r ent
Thr eshol d ( m A)
—
70
80
90
100
70
80
90
100
70
80
90
100
70
80