MAX16805 Datasheet, PDF (15/19 Pages) Maxim Integrated Products – EEPROM-Programmable, High-Voltage, 350mA LED Drivers with LED Current Foldback

EEPROM-Programmable, High-Voltage, 350mA
LED Drivers with LED Current Foldback
Thermal Foldback Knee Point (TFK)
Register (0x03), MAX16806
The TFK register is a 4-bit register that sets the thermal
knee. Only the first 4 bits of the data byte program the
TFK register. The remaining 4 bits are ignored (see Table
6). The MAX16806 initiates dimming once the differential
voltage between TFP/SCL and TFN/SDA drops below the
programmed thermal foldback knee. The factory-default
register value is 1.174V, which corresponds to the
MAX6613 thermal sensor output to +60°C.
Thermal Foldback Slope Gain Register
(0x04), MAX16806
Thermal Foldback Slope Gain register is a 2-bit register
that sets the gain after the thermal foldback knee. Only
the first 2 bits of the data byte program the Thermal
Foldback Slope Gain register. The remaining 6 bits are
ignored (see Table 7). The factory-default register value
is 4V/V.
Table 6. Thermal Foldback Knee
THERMAL FOLDBACK
KNEE POINT (°C)
(MAX6613)
60
65
70
75
80
85
90
96
101
106
111
116
121
126
131
136
THERMAL FOLDBACK
KNEE POINT (mV)
1174
1118
1062
1006
950
894
838
782
726
670
615
559
503
447
391
335
BIT 3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
BIT 2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
BIT 1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
BIT 0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
HEX
(0x00)
(0x01)
(0x02)
(0x03)
(0x04)
(0x05)
(0x06)
(0x07)
(0x08)
(0x09)
(0x0A)
(0x0B)
(0x0C)
(0x0D)
(0x0E)
(0x0F)
Table 7. Thermal Foldback Slope Gain
THERMAL FOLDBACK
SLOPE GAIN (V/V)
16
12
8
4
BIT 1
0
0
1
1
BIT 0
0
1
0
1
HEX
(0x00)
(0x01)
(0x02)
(0x03)
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