MAX16824EVKIT+ Maxim Integrated Products, MAX16824EVKIT+ Datasheet - Page 2

• Manufacturer Part Number: MAX16824EVKIT+
• Description: KIT EVAL FOR MAX16824
• Manufacturer: Maxim Integrated Products

Specifications of MAX16824EVKIT+

• Current - Output / Channel: 100mA
• Outputs And Type: 3, Non-Isolated
• Voltage - Output: 26.3V
• Features: Dimmable
• Voltage - Input: 6.5 ~ 28V
• Utilized Ic / Part: MAX16824
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

MAX16824 Evaluation Kit
7) Connect the logic function generator output to each
8) Connect one LED load anode to each LED output
9) Connect each LED load cathode to the correspond-
10) Enable the power-supply output.
11) Enable the logic function generator signal output.
12) Verify that the attached LEDs are illuminated.
The MAX16824 EV kit demonstrates a high-voltage,
3-channel, linear high-brightness LED driver using the
MAX16824 IC in a 16-pin TSSOP surface-mount pack-
age. This EV kit is configured to supply an LED current
of 100mA per channel. The MAX16824 IC controls the
LED current by maintaining a 200mV drop across each
external sense resistor (R1, R2, and R3). The EV kit
operates from a 0.5A, 6.5V to 28V rated power supply.
The three independent PWM inputs (PWM1, PWM2,
and PWM3) control dimming for each channel. Each
PWM input functions as an active-high enable for the
corresponding LED channel.
The MAX16824 features an exposed paddle that uses
the top-layer and bottom-layer PCB copper as a
heatsink. The exposed paddle connects to GND.
The MAX16824 EV kit can drive three separate LED
loads. Each LED load can consist of multiple LEDs con-
nected in series. The LED load’s forward voltage can
be up to 26.3V. The EV kit drives LEDs rated for at least
100mA. Proper heat sinking of the LEDs is important for
optimum LED performance and durability.
2
Detailed Description of Hardware
_______________________________________________________________________________________
of the PWM pads (PWM1, PWM2, and PWM3).
pad (LED1+, LED2+, or LED3+).
ing LED input pad (LED1-, LED2-, or LED3-).
LED Load Configuration
The current for each MAX16824 EV kit LED channel
(I
three sense resistors (R1, R2, and R3, respectively).
See the equation below to select a different LED cur-
rent and a new resistor value. If designing for a higher
LED current, verify that the desired current setting does
not exceed the power rating of the corresponding resis-
tor (R1, R2, or R3) or the LED load. Do not set the LED
current above 150mA. Use the following equation to
calculate the value of the new resistor:
where I
resistor value required to set the desired current of the
LED channel.
The MAX16824 IC operates in linear mode. As a result,
the IC can dissipate significant power if operated using a
high input voltage and a small V
pation may cause the IC to go into thermal shutdown.
Refer to the Thermal Protection section in the MAX16824/
MAX16825 IC data sheet for more information.
The MAX16824 EV kit features three independent PWM
pads used for controlling LED brightness for each
channel. Each channel can have a different dimming
signal pattern. Use a digital PWM signal with a 5V logic
level and a switching frequency between 100Hz and
5kHz. Frequencies lower than 100Hz can introduce
flickering in the light output. Vary the duty cycle of the
signal to adjust the LED brightness. LED brightness
increases as the duty cycle increases and vice versa.
When the PWM signal’s duty cycle is 100%, the LEDs
are continuously on. At 0% duty cycle, the outputs are
disabled.
LED1
, I
LED_
LED2
is the desired LED current and R_ is the
, and I
R
LED3
_
=
and Thermal Protection
) is configured to 100mA by
200
Output Current Setting
I
LED
mV
_
High Input Voltage
FLED
. High-power dissi-
LED Dimming