MAX16806EVCMAXQU+ Maxim Integrated Products, MAX16806EVCMAXQU+ Datasheet - Page 7

• Manufacturer Part Number: MAX16806EVCMAXQU+
• Description: EVAL KIT FOR MAX16806
• Manufacturer: Maxim Integrated Products

Specifications of MAX16806EVCMAXQU+

• Current - Output / Channel: 350mA
• Outputs And Type: 1, Non-Isolated
• Features: Dimmable, Extra 5V Output
• Voltage - Input: 5.5 ~ 40V
• Utilized Ic / Part: MAX16806
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -

Binning Adjustment takes 16 different values from
103mV to 198mV, and this voltage is used as the cur-
rent-sense reference for controlling the LED current.
Ramp Peak value takes eight different values from
1.55V to 2.88V, and this voltage decides the peak volt-
age of the internal 200Hz reference ramp. Changing
the ramp peak voltage affects the analog dimming and
the dimming during current and thermal foldback.
Current Foldback Threshold takes eight values from
11.4V to 16.4V, and this value decides the supply volt-
age above which the current foldback feature starts
dimming LEDs (if the CFD jumper is open to enable
current foldback). The current foldback range is 1.2
times the ramp peak value if bit 3 of the current fold-
back threshold register is not set. The Double Current
Foldback Range checkbox sets bit 3 of the current
foldback threshold register when checked to make the
current foldback range 2.4 times the ramp peak value.
Thermal Foldback Knee Point takes 16 different values
from +60°C to +136°C, controlling the thermal foldback
feature based on the voltage level at the TFIN input.
Temperature-sense input TFIN is compatible to the out-
put of the MAX6613 temperature sensor, or an equiva-
lent device. Each temperature setting corresponds to a
reference voltage internal to the MAX16806 that is equal
to the output voltage generated by a MAX6613, or an
equivalent device. When the voltage at the TFIN input
reduces to the voltage corresponding to the selected
thermal foldback knee-point temperature, the thermal
foldback feature starts dimming the LED. Connect the
output of a MAX6613 temperature sensor, or an equiva-
lent device, to the TFIN input or apply the respective
voltage to TFIN to evaluate this feature. Disconnect the
I
the functions use the same device pins.
Thermal foldback knee point inputs TFN/TFP should not
be left open when not used, as it will enable the thermal
foldback function and reduce the LED brightness. In the
MAX16806 EV kit, resistors R5 and R6 provide the nec-
essary biasing for TFN/TFP inputs and disable the ther-
mal foldback function. The TFN input is connected to
GND through R6 (50kΩ) and the TFP input is connected
to +5V through R5 (50kΩ). These resistors do not affect
the normal functionality of the thermal foldback input, as
well as the I
user application circuit for proper operation.
2
C interface when connecting signals to TFIN, as both
2
C interface, and should be used in the end-
_______________________________________________________________________________________
Thermal Foldback Knee Point
Current Foldback Threshold
Binning Adjustment
MAX16806 Evaluation Kit/
Thermal Foldback Slope takes four different
values, and the selected value is multiplied with the dif-
ference between the voltage input at TFIN and the inter-
nal reference voltage that corresponds to the thermal
foldback knee point (this difference voltage is a mea-
sure of the set thermal foldback knee point and the
sensed temperature), with the resultant voltage used to
decide the dimming. As this resultant voltage increases,
the LED brightness reduces. When it becomes equal to
the peak amplitude of the internal ramp, the dimming is
complete and the LED is fully off.
Thermal Foldback Dim Clamp takes eight values
between 40% and 100%. This value is the minimum per-
centage of the output brightness that will be reached
when MAX16806 is dimming during thermal foldback.
To program the EEPROM registers, the input supply
voltage should be kept at 22V. Open the CFD jumper to
enable current foldback to prevent excessive power
dissipation due to high input voltage. Load the values
to be stored into the EEPROM to dynamic registers by
using the respective pulldown menu and the check-
box. Click on the Program Data button. The software
writes hex code 0xCA to the password register (0xFF)
to enable EEPROM programming, and then makes a
write operation to the EEPROM program enable register
to initiate the EEPROM programming cycle. Data written
into the EEPROM program enable register does not
have any significance. The MAX16806 stores the con-
tents of the dynamic registers to EEPROM. A
Programming EEPROM Data Successful message
appears. This indicates that the dynamic register con-
tents are stored into the EEPROM and programming is
complete.
If the current foldback is not disabled and the LED is on, it
is turned off during EEPROM programming. During the
next power-up, the new EEPROM contents are loaded
into the dynamic registers. To load the EEPROM contents
to dynamic registers during normal operation, click on the
Recall Data button. The software makes a write operation
to EEPROM content transfer register (0x06). This initiates
the transfer of EEPROM contents to dynamic registers.
The data written to the EEPROM content transfer register
do not have any significance. The dynamic register con-
tents are displayed after the transfer is complete.
Evaluation System
Programming EEPROM Registers
Thermal Foldback Clamp Level
Thermal Foldback Slope
7