Linear Technology DC2218A Quick setup guide

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DEMO MANUAL DC2218A
DESCRIPTION
LT3965EFE
8-Switch Matrix LED Dimmer
Demonstration circuit DC2218A is a matrix LED dimmer
system featuring the LT3965 8-switch matrix LED dim-
mer IC. There are 16 500mA LEDs that can be individually
turned on, off, or PWM dimmed with two 8-switch LED
dimmer LT3965 ICs. The two strings of LEDs are driven
with two buck LED driver outputs of the LT3797 triple LED
controller IC. The third channel of the LT3797 serves as a
30V pre-boost voltage regulator to provide a proper input
voltage to the two buck LED driver channels. DC2218A
can be driven from a 9V to 30V input and can survive
transients up to 36V.
A pre-programmed DC2026C Linduino™One demo circuit
is attached to the DC2218A matrix LED dimmer shield to
create a full matrix LED dimmer system. With the Linduino
One attached as an under-shield microcontrollerboard, the
entire system can be powered from either a 9V to 36V lab
power supply or battery connected to the EMIVIN banana
jacks or from a 12V 4A+ AC/DC converter connected to
the J7 barrel jack connector.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
Linduino and QuikEval are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
PERFORMANCE SUMMARY
DC2218A can be operated by connecting 12V power to the
input and selecting 7 pre-programmed patterns withrotary
switch S1. When connected to a PC through a USB cable,
an eighth setting of S1 (position 7) allows DC2218A to be
operated with a graphical user interface (GUI).
The LT3965 data sheet gives a complete description of
the part, operation and applications information. The data
sheet must be read in conjunction with this demo manual
for demonstration circuit DC2218A. The LT3965EFE is
assembled in a 28-lead plastic TSSOP (FE) package with
a thermally enhanced ground pad. Proper board layout
is essential for maximum thermal performance. See the
data sheet section Layout Considerations.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2218A
Specifications are at TA= 25°C
PARAMETER CONDITIONS MIN TYP MAX UNITS
Input Voltage (EMIVIN or J7 Barrel Connector) 8 36 V
RTCLK Switching Frequency Set by LTC6900 350 kHz
PWM Dimming Frequency Switching Frequency Divided by 2048 170 Hz
ILED 16 LEDs, 8 LEDs Each LT3965 500 mA
30VOUT LT3797 CH3 Pre-Boost Voltage 30 V
I2C Serial Communications Frequency 400 kHz
Barrel Jack Connector Size (for 12V 4A+ Supply) PJ-002AH Power Jack Connector J7 2.1 mm ID

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DEMO MANUAL DC2218A
QUICK START PROCEDURE
How to Operate Pre-Programmed Patterns 0-6 (S1)
Demonstration circuit DC2218A is easy to set up to evalu-
ate the performance of the LT3965 matrix LED dimming
system and its pre-programmed patterns.
NOTE:The included DC2026C Linduino One is pre-
programmed to work with DC2218A. If the .ino code is
mistakenly changed or overwritten, new .ino code must
be uploaded from Linear’s website.
NOTE: An acrylic shield has been assembled over the LEDs
toprotect theuser’s eyes from extremelybright light.Please
make sure that the shield is in place and any necessary
protective eyewear is worn before looking directly at the
bright LEDs and their patterns.
Follow the procedure below:
1. Set the PATTERN SELECT rotary switch S1 to any posi-
tion between 0 and 6. Position 7 is reserved for use
with the GUI (graphical user interface).
2. Connect 12V power to either the EMIVIN and GND
banana jacks or to the J7 2.1mm (inside diameter)
barrel jack.
3. Observe the red LED indicator light (D32). When it
begins flashing, then the board is ready to start up.
4. When the red LED (D32) is flashing, push the Push to
Start button S3.
5. Observe the LED patterns and adjust the speed, bright-
ness and pattern of the LEDs with the manual blue
potentiometer R14.
6. Change the Pattern Select rotary switch to positions
0-6 to observe different patterns.
7. Press the Reset button S2 to start over again.
How to Operate with Graphical User Interface (GUI)
Demonstration circuit DC2218A can be connected with a
PC via USB cable and controlled with a GUI.
NOTE:The included DC2026C Linduino One is pre-
programmed to work with DC2218A and to interface with
the LT3965 GUI. If the .ino code is mistakenly changed
or overwritten, new .ino code must be uploaded from
Linear’s website.
NOTE: An acrylic shield has been assembled over the LEDs
toprotect theuser’s eyes from extremelybright light.Please
make sure that the shield is in place and any necessary
protective eyewear is worn before looking directly at the
bright LEDs and their patterns.
Follow the procedure below:
1. If never done before, download and install QuikEval™
from Linear’s website under design tools and software
at http://www.linear.com/designtools/software/#Data
QuikEval is your link to receiving the latest LT3965 GUI
software and to run the GUI. Installation of QuikEval
properlyinitializes theserialport driveron thecomputer
to work with the Linduino One USB connection.
If QuikEval is already installed, skip step 1, or update
QuikEval to get the LT3965 GUI.

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DEMO MANUAL DC2218A
QUICK START PROCEDURE
2. Remove power and the USB cable from the DC2218A
inputs.
3. Turnthe PATTERN SELECTrotaryswitch S1 to position
7 for the GUI.
4. Connect 12V power to either the EMIVIN and GND
banana jacks or to the J7 2.1mm (inside diameter)
barrel jack.
5. Connect a USB cable between a PC and the USB con-
nector on the under-shield DC2026C (which arrives
includedin theDC2218Apackage andpre-programmed
with DC2218A .ino code).
6. Launch the LT3965 GUI from QuikEval.
7. Click Connect to DC2218A to connect to the DC2218A
with the GUI.
8. Observe the GUI program starts at ALL CHANNEL
MODE screen and the LEDs on the PCB are all off.
9. Start creating and testing I2C commands with ALL
CHANNEL MODE, SINGLE CHANNEL MODE, BROAD-
CAST, DIGITAL WRITE, READ REGISTERS, and LED
SETTINGS pages.
NOTE: An LT3965 GUI user guide is posted on the Linear
blog site. It contains the GUI commands and details.
Please contact Linear support for help with the GUI and
User Guide.

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DEMO MANUAL DC2218A
QUICK START PROCEDURE
Figure 1. DC2218A Test Setup Photo

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DEMO MANUAL DC2218A
S1 PATTERN SELECT
ROTARY SWITCH
S2 RESET BUTTON
TO RESET MICRO
S3 PUSH TO START
WHEN RED LED D32
IS FLASHING
USB CABLE CONNECTION
UNDER PCB FOR GUI
2.1mm INSIDE
DIAMETER
BARREL JACK J7
12V DC
OKAY TO NOT CONNECT
THESE TURRETS
BANANA JACKS
V
IN
OR
DC2026C LINDUINO ONE
PRE-PROGRAMMED AND
INSTALLED UNDER DC2218A
R14 POTENTIOMETER
MANUAL INTERACTION
WITH S1 PATTERNS 0-6
+
–
QUICK START PROCEDURE
Figure 2. DC2218A Top Silkscreen and Component Reference Drawing

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DEMO MANUAL DC2218A
PWM ON, CONNECT LED STRING
START PUSH BUTTON
STARTS WITH ALL LEDS OFF AND USES PUSH BUTTON START
PROGRAMMED IN EMBEDDED C++ AND PRE-LOADED ON DC2026C (LINDUINO ONE)
LT3797 STARTUP (PWM LOW)
CHARGE PUMP LT3965 ON
SCM WRITES TO ALL CHANNELS – TURN LEDS OFF, 1 LED OPEN AND SHORT
CHECK
ROTARY SWITCH
POSITION
GUI
7
Fade Wave
6
4
5
3
2
1
0
INTERACTIVE
KNOB
Side Bend Steer
Side-to-Side Steer
High Beam Blank
PWM All 16
LEDs are OFF, LT3965 SWITCHES are ON.
WAIT FOR Blinking indicates ready to start.
CONNECT POWER
PRESS RESET
WAIT FOR ALERT FLAG
LINDUINO STARTUP
PULL PWM OFF
MAIN
LOOP
Wave
Comet
PRE-PROGRAMMED PATTERNS
Figure 3. DC2218A Attached Linduino One Pre-Programmed Software Flow-Chart
S1 Pattern Select Position
0. Comet:A comet of light runs around the sixteen LEDs
changing PWM dimming brightness quickly increasing
and decreasing at rates that look like a ball of fire zipping
around the LEDs. The interactive potentiometer controls
the speed of the comet.
1. Wave:A wave of light from right to left and from left to
right changing PWM dimming brightness quickly increas-
ing and decreasing at rates that look like a wave running
from one side of the LEDs to the other
. The interactive
potentiometer controls the speed of the wave.
2. Side-to-Side Steer:Center headlight LEDs stay on to
face directly forward while the right and left side LEDs
turn on with brightness proportional to the amount that
the steering wheel (interactive potentiometer) is turned.
3. High Beam Blank:While the low beam Is on 100%
brightness, the sections of the high beam turn OFF.
Although the blank spots would be controlled by a so-
phisticated camera detecting an object in front of a car
to determine which high beam LEDs to turn off or dim,
the section on DC2218A is controlled by turning the
interactive potentiometer.
4. Side Bend Steer:All sixteen LEDs adjust PWM dim-
ming duty cycle and brightness based upon the position
of the steering wheel (interactive potentiometer). This
pattern represents a light that bends around the side of
a car, projecting a turning headlight pattern that is linked
to the steering wheel.
5. PWM All 16:All sixteen LEDs have the same PWM
dimming and brightness level that is set by the interactive
potentiometer. They range from OFF to ON In increments
of 1/256 PWM dimming.
6.Fade Wave:Usingthe PWM dim WITH FADE commands,
a wave of light is created by fading the LED brightnesses
up and down. WITH FADE option uses the logarithmic fade
function of the LT3965 and allows the brightness to fade
from low to high or from high to low with a single I2C bus
command. This pattern has low bus traffic.
7. GUI:GRAPHICAL USER INTERFACE position setting –
Use this position when connecting to the GUI. See details
above for downloading and connecting to the GUI via the
USB cable connection of DC2026C.

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DEMO MANUAL DC2218A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
LT3965 Matrix LED Dimmer Circuit Components
1 2 C1, C2 CAP., 0.1µF, X7R, 50V, 10%, 0402 MURATA, GRM155R71H104KE14D
2 2 C3, C6 CAP., 1µF, X7R, 50V, 10%, 0805 MURATA, GRM21BR71H105KA12L
3 0 C42-C59(OPT) CAP., OPTION, 0402
4 2 D4, D5 SCHOTTKY, RECTIFIER, 60V, 1A, SOD-123F NXP., PMEG6010CEH, 115
5 2 D12, D13 SCHOTTKY, RECTIFIER, 40V, 1A, SOD-123F NXP., PMEG4010CEH, 115
6 16 D15-D30 DIODE, PMEG4010CEJ SOD-323 NXP., PMEG4010CEJ, 115
7 2 Q4, Q5 TRANSISTOR, SOT-23 DIODES INC., FMMT593TA
8 2 R1, R2 RES., 49.9k, 1/10W, 1% 0603 VISHAY, CRCW060349K9FKEA
9 2 R3, R5 RES., 9.09k, 1/10W, 1%, 0603 VISHAY, CRCW06039K09FKEA
10 7 R4, R6, R7, R8, R18, R19, R83 RES., 10k, 1/16W, 1% 0402 VISHAY, CRCW040210K0FKED
11 2 R44, R47 RES., 1k, 1/10W, 1%, 0603 VISHAY, CRCW06031K00FKEA
12 2 U1, U2 I.C. LT3965EFE TSSOP28 LINEAR TECH., LT3965EFE#PBF
LT3797 Boost-then-Dual-Buck LED Driver Circuit Components
1 4 C4, C5, C12, C17 CAP., 0.1µF, X7R, 100V, 10%, 0603 MURATA, GRM188R72A104KA35D
2 1 C9 CAP., 22nF, X7R, 25V, 10%, 0402 MURATA, GRM155R71E223KA61D
3 2 C19, C37 CAP., 2200pF, X7R, 25V, 10%, 0402 MURATA, GRM155R71E222KA01D
4 2 C20, C21 CAP., 22µF, X5R, 10V 20%, 0603 MURATA, GRM188R61A226ME15D
5 1 C22 CAP., 1000pF, C0G, 25V, 5%, 0402 MURATA, GRM1555C1E102JA01D
6 1 C23 CAP., ALUM., 33µF, 50V, 6.3X7.7 PANASONIC, EEHZA1H330XP
7 1 C24 CAP., 4.7µF, X7R, 50V 10%, 1210 MURATA, GRM32ER71H475KA88L
8 7 C25-C30, C39 CAP., 10µF, X5R, 50V 10%, 1206 MURATA, GRM31CR61H106KA12L
9 1 C31 CAP., 1µF, X7R, 50V, 10%, 0805 MURATA, GRM21BR71H105KA12L
10 2 C32, C33 CAP., 1µF, X7R, 16V, 10%, 0603 MURATA, GRM188R71C105KA12D
11 1 C34 CAP., 0.22µF, X5R, 10V 10%, 0603 MURATA, GRM188R61A224KA01D
12 1 C35 CAP., 0.1µF, X7R, 16V, 10%, 0603 MURATA, GRM188R71C104KA01D
13 1 C36 CAP., 10µF, X5R, 10V, 10%, 0603 MURATA, GRM188R61A106KE69D
14 1 C38 CAP., 0.1µF, X7R, 50V, 10%, 0402 MURATA, GRM155R71H104KE14D
15 0 C40, C41(OPT) CAP., 0805
16 2 D1, D2 DIODE, DFLS260, POWER-DI-123 DIODES/ZETEX, DFLS260-7
17 1 D3 DIODE, PDS360, POWER-DI-5 DIODES/ZETEX, PDS360-13
18 6 D6-D11 DIODE, PMEG6010CEJ SOD-323 NXP., PMEG6010CEJ, 115
19 1 FB1 BEAD, CHIP, 742792150 WURTH ELEKTRONIK, 742792150
20 2 L1, L2 INDUCTOR, 33µH, WURTH ELEKTRONIK, 7447789133
21 1 L3 INDUCTOR, 15µH WURTH ELEKTRONIK, 7443551151
22 1 L4 IND., 47µH, SD SERIES, IND-SD25 EATON BUSSMANN, SD25-470-R
23 1 L6 INDUCTOR, 10µH WURTH ELEKTRONIK, 7443251000
24 2 M1, M2 N-CH MOSFET, Si7308DN, POWERPAK-1212-8 VISHAY, Si7308DN-T1-GE3
25 1 M3 N-CH MOSFET, Si7850DP, POWERPAK SO8 VISHAY, Si7850DP-T1-GE3
26 2 M4, M5 P-CH MOSFET, Si7611DN, POWERPAK-1212-8 VISHAY, Si7611DN-T1-GE3 (LEAD-FREE #)

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DEMO MANUAL DC2218A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
27 1 R10 RES., 47.5k, 1/16W, 1% 0402 VISHAY, CRCW040247K5FKED
28 2 R11, R12 RES., 5.6k, 1/16W, 5% 0402 VISHAY, CRCW04025K60JNED
29 1 R13 RES., 15k, 1/16W, 5% 0402 VISHAY, CRCW040215K0JNED
30 1 R15 RES., 0.02Ω, 0.5W, 1% 1206 SUSUMU, RL1632R-R020-F
31 2 R16, R17 RES., 0.05Ω, 0.5W, 1% 1206 SUSUMU, RL1632R-R050-F
32 2 R25, R26 RES., 0.5Ω, 0.5W, 1% 1206 SUSUMU, RL1632R-R500-F
33 2 R28, R31 RES., 44.2k, 1/16W, 1% 0402 VISHAY, CRCW040244K2FKED
34 3 R29, R30, R35 RES., 1M, 1/10W, 1% 0603 VISHAY, CRCW06031M00FKEA
35 1 R32 RES., 43.2k, 1/16W, 1% 0402 VISHAY, CRCW040243K2FKED
36 3 R33, R38, R39 RES., 10k, 1/10W, 1% 0603 VISHAY, CRCW060310R0FKEA
37 1 R40 RES., 249k, 1/16W, 1% , 0402 VISHAY, CRCW0402249KFKED
38 1 R41 RES., 38.3k, 1/16W, 1% , 0402 VISHAY, CRCW040238K3FKED
39 2 R42, R43 RES., 100k, 1/10W, 1%, 0603 VISHAY, CRCW0603100KFKEA
40 1 R45 RES., 100k, 1/16W, 1% , 0402 VISHAY, CRCW0402100KFKED
41 1 U3 I.C., LT3797EUKG QFN(52)(UKG)-7MMX8MM LINEAR TECH., LT3797EUKG#PBF
Additional Demo Board Circuit Components
1 1 DC2026C LINDUINO DEMO BOARD
2 2 C7, C8 CAP., 0.1µF, X7R, 16V, 10%, 0603 MURATA, GRM188R71C104KA01D
3 3 C10, C11, C13 CAP., 1µF, X7R, 16V, 10%, 0603 MURATA, GRM188R71C105KA12D
4 1 C14 CAP., 0.22µF, X5R, 6.3V 10%, 0402 MURATA, GRM155R60J224KE01D
5 1 C15 CAP., 1µF, X7R, 50V, 10%, 0805 MURATA, GRM21BR71H105KA12L
6 1 C16 CAP, 22µF, X7R, 6.3V, 20%, 1206 MURATA, GRM31CR70J226KE19L
7 1 C18 CAP, 22pF, NPO, 5% 50V, 0402 MURATA, GRM1555C1H220JA01D
8 1 D14 LED, GREEN, DIFFUSED, 0805 AVAGO, HSMG-C170
9 1 D31 LED, YELLOW, DIFFUSED, 0805 AVAGO, HSMY-C170
10 1 D32 LED, RED WURTH ELEKTRONIK, 150080SS75000
11 1 L5 IND, 33µH TOKO, A914BYW-330M=P3
12 16 LED1-LED16 LED, XLAMP XP-E2 SERIES CREE INC., XPEBWT-L1-0000-00D50
13 3 Q1, Q2, Q3 TRANSISTOR, MOSFET, N-CH 60V, 150mA, SOT-23 DIODES INC., VN10LFTA
14 1 R9 RES., 57.6k, 1/10W, 1%, 0603 VISHAY, CRCW060357K6FKEA
15 1 R14 POT., 10k, 10%, 1 TURN BOURNS, 91A1A-B28-A15L
16 3 R20, R21, R48 RES., 1k, 1/10W, 1%, 0603 VISHAY, CRCW06031K00FKEA
17 1 R22 RES., 10k, 1/10W, 1%, 0603 VISHAY, CRCW060310K0FKEA
18 1 R23 RES., 604k, 1/16W, 1% , 0402 VISHAY, CRCW0402604KFKED
19 1 R24 RES., 200k, 1/16W, 1% , 0402 VISHAY, CRCW0402200KFKED
20 1 R27 RES., 100Ω, 1/10W, 5% 0603 VISHAY, CRCW0603100RJNEA
21 3 R34, R36, R37 RES., 5.1k, 1/10W, 5% 0603 VISHAY, CRCW06035K10JNEA
22 1 R46 RES., 2.49k, 1W, 5% 2512 VISHAY, CRCW25122K49FKEG
23 4 R49, R50, R51, R52 RES., 0Ω, 1/10W, 0603 VISHAY, CRCW06030000Z0EA
24 2 R53, R54 RES., 0Ω, 1/16W, 0402 VISHAY, CRCW04020000Z0ED

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DEMO MANUAL DC2218A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
25 0 R55, R81, R82(OPT) RES., OPTION, 0603
26 0 R56-R79(OPT) RES., OPTION, 0402
27 0 R80(OPT) RES., OPTION, 2512
28 1 U4 I.C., LTC6900, TSOT-23-5 LINEAR TECH., LTC6900CS5#PBF
29 1 U5 I.C., LT6656 TSOT-23-6 LINEAR TECH., LT6656ACS6-3#PBF
30 1 U6 I.C., LT3470AEDDB, DFN8DDB LINEAR TECH., LT3470AEDDB#PBF
Hardware: For Demo Board Only
1 6 E1-E6 TESTPOINT, TURRET, 0.094" pbf MILL-MAX, 2501-2-00-80-00-00-07-0
2 6 E7-E12 TESTPOINT, TURRET, 0.064" MTG. HOLE MILL-MAX, 2308-2-00-80-00-00-07-0
3 10 JP1(4 ea), JP2(4 ea), JP3, JP4 HEADER, 3 PIN 0.079" SINGLE ROW WURTH ELEKTRONIK, 62000311121
4 10 xJP1(4 ea), xJP2(4 ea), xJP3, xJP4 SHUNT, 0.079" CENTER WURTH ELEKTRONIK, 60800213421
5 0 J1, J3, J12, J13(OPT)
6 0 J2 (OPT) R ANGLED HEADER, 2X10, 0.1" WURTH ELEKTRONIK, 61302021021
7 1 J4 HEADER, 10PIN, 0.100 SINGLE ROW WURTH ELEKTRONIK, 61301011121
8 2 J5, J9 HEADER, 8PIN, 0.100 SINGLE ROW WURTH ELEKTRONIK, 61300811121
9 0 J6 (OPT) R ANGLED SOCKET HEADER, 2X10, 0.1" WURTH ELEKTRONIK, 613020243121
10 1 J7 THROUGH HOLE CONNECTOR, POWER JACK, 2.1mm CUI INC., PJ-002AH
11 1 J8 HEADER, 6PIN, 0.100 SINGLE ROW WURTH ELEKTRONIK, 61300611121
12 2 J10, J11 CONNECTOR, BANANA JACK KEYSTONE, 575-4
13 8 MH1-MH8 STAND-OFF, NYLON, 22.2mm WURTH ELEKTRONIK, 702938000
14 2 ACRYLIC-SHIELD ACRYLIC-SHIELD, 1/8" THICK, SMOKE (GRAY COLOR) JB MACHINING, 2074
15 6 STANDOFF NYLON, 0.75" KEYSTONE, 1903D
16 6 SPACER NYLON, 0.5" KEYSTONE, 886
17 6 SCREW NYLON, 1.25" KEYSTONE, 9340
18 1 S1 SWITCH, ROTARY, 8 POSITIONS APEM, PT65526
19 1 S2 SWITCH, PUSHBUTTON, MINIATURE WURTH ELEKTRONIK, 434111025826
20 1 S3 SWITCH, B3SL SERIES OMRON, B3SL-1002P

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DEMO MANUAL DC2218A
SCHEMATIC DIAGRAM