MAX16803EVKIT+BJT Maxim Integrated Products, MAX16803EVKIT+BJT Datasheet - Page 3

• Manufacturer Part Number: MAX16803EVKIT+BJT
• Description: EVAL KIT FOR MAX16803
• Manufacturer: Maxim Integrated Products

Specifications of MAX16803EVKIT+BJT

• Current - Output / Channel: 1A
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 38V
• Features: Dimmable, Extra 5V Output
• Voltage - Input: 6.5 ~ 40V
• Utilized Ic / Part: MAX16803
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

An external resistor can be added at the input to the
device, or in series with LED, to reduce the power dissi-
pation in the BJT. The resistor’s power rating should be
higher than I
rent, and R is the value of the added resistor).
The BJT junction-temperature rise above the ambient
can be calculated by multiplying the power dissipated
in BJT by the sum of the thermal resistances of BJT
from junction to ambient. To reduce the temperature
rise, either the power dissipation or the thermal resis-
tance should be reduced. It is a good practice to
enlarge surface area of the board, fill copper on both
sides, and add vias from top to bottom for reducing the
thermal resistance.
Caution: The board should support 3W power dissipa-
tion for BJT at T
is considerably higher, BJT junction temperature can
reach unsafe levels and the device can be damaged.
Figure 1. MAX16803EVKIT+BJT Schematic
VIN+
GND
2
J1
R (where I is the input current, or LED cur-
A
2
1
= +30°C. If the power dissipation in BJT
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
1µF
C1
MAX16803EVKIT+BJT Evaluation Kit+
VIN+
GND
DIM
+5V
EN
J2
J3
2
1
1
2
3
15
13
2
3
IN
IN
EN
DIM
V5
11
MAX16803
J7
TP1
0.1µF
C2
2
U1
Two-pin jumper J2 controls the EN pin of the
MAX16803 and closing of J2 enables the device.
Three-pin jumper J4 can select between three different
output current settings. Three-pin jumper J3 controls
the PWM input of the device. Table 1 lists the jumper
options.
Table 1. Jumpers J1, J2, and J3 Functions
JUMPER
1
TP2
J4
J3
J2
GND
12
OUT
OUT
CS+
CS-
PWM disabled
and always on
PINS 1-2
10
16
1
9
1A
SHUNT POSITION AND FUNCTION
U1 enabled
CLOSED
1
2
J5
Q1
MJD31CTF
TP3
TP4
PWM disabled
and always off
Jumper Selection
R2
0.27Ω
R1
0.2Ω
PINS 2-3
750mA
1
2
1
2
3
J6
J4
LED+
LED-
1
2
3
PWM enabled
U1 disabled
450mA
OPEN
3