iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 1
General Description
Features
The iML8683 is a Three Terminal Current
Controller (TTCC) for regulating the current flowing
through an LED string.
The application of the iML8683 is configured in
parallel with an LED string. The iML8683 can work
as voltage controlled current source, current
regulator, or cut-off. It is suitable for the applications
adopting periodical AC voltage source.
The PCB layout is also very flexible to meet
various shape requirements. It is especially suitable
for replacing incandescent light bulb and linear type
fluorescent lamp.
System
- All solid state components.
- No electrolytic capacitor required.
- Compact size to minimize mechanical cost.
- Driver-on-board and chip-on-board available which
minimize process flow and assembly cost.
- High PF and Low THD performance.
- High efficiency achieved.
- Flexible PCB layout style.
- Wide range of LED forward voltage selection.
- Distributed heat to several chips.
- TRIAC dimmable.
Chip
- 88V input sustaining voltage.
- <3V dropout voltage for up to 150mA regulating current
Typical Application Circuit
Applications
VAC
BD
LED2
LED1
Q1
iML3160
U2
iML8683
U3
iML8683
Rz
ZD
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
LED3
U1
iML8683
MS1
MS2
K
CS
NC
A
ILED
Rectified
VAC
t
t
AC LED lighting engine.
LED light bulb.
LED light tube.
LED down-light and ceiling light
LED flat panel light
Pin Diagram (Top View)
SOT-89- 5L
32
1
CS MS1
MS2K
A
5 4
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 2
Ordering Information
Package Type: DFN – 2mm x 2mm – 6L (Halogen Free)
Part Number
Tape and Reel
1st Line
Marking
Regulating Current (mA)
(Mode 0, MS1 and MS2 connected to pin K)
iML8683NL-C1
iML8683NL-C1-TR
i83C1
40
iML8683NL-C2
iML8683NL-C2-TR
i83C2
66
iML8683NL-C3
iML8683NL-C3-TR
i83C3
52
iML8683NL-D1
iML8683NL-D1-TR
i83D1
80
iML8683NL-D2
iML8683NL-D2-TR
i83D2
130
iML8683NL-D3
iML8683NL-D3-TR
i83D3
104
iML8683NL-ADJ
iML8683NL-ADJ-TR
i83AD
Determined by external resistor only
Package Type: SOT – 89 – 5L (Halogen Free)
Part Number
Tape and Reel
1st Line
Marking
Regulating Current (mA)
(Mode 0, MS1 and MS2 connected to pin K)
iML8683BP-C1
iML8683BP-C1-TR
i8683C1
40
iML8683BP-C2
iML8683BP-C2-TR
i8683C2
66
iML8683BP-C3
iML8683BP-C3-TR
i8683C3
52
iML8683BP-D1
iML8683BP-D1-TR
i8683D1
80
iML8683BP-D2
iML8683BP-D2-TR
i8683D2
130
iML8683BP-D3
iML8683BP-D3-TR
i8683D3
104
iML8683BP-ADJ
iML8683BP-ADJ-TR
i8683AD
Determined by external resistor only
Dice
Part Number
Regulating Current (mA)
(Mode 0, MS1 and MS2 connected to pin K)
iML8683BZ-C1
40
iML8683BZ-C2
66
iML8683BZ-C3
52
iML8683BZ-D1
80
iML8683BZ-D2
130
iML8683BZ-D3
104
iML8683BZ-ADJ
Determined by external resistor only
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 3
Block Diagram
Thermal
Protection Logic
Circuit
MS2
A
CS
+
VAK
-IAK
MS1
K
REXT
I-V Curve
VAK
IAK
0VDROP
IPEAK0
IPEAK1
IPEAK2
IPEAK3
Mode 0
Mode 1
Mode 2
Mode 3
Cx / Dx Options
VAK
IAK
0VDROP
IPEAK Mode 0 ~ Mode 3
ADJ Options
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 4
Pin Descriptions
Pin Name
Pin Number
Pin Function
DFN
SOT-89
CS
1
5
Current sense pin. Connected to negative end of LED string.
A
3
1
Regulating current input pin. Connected to positive end of LED
string.
K
4
2
Regulating current output pin.
MS2
5
3
Mode selection pin 2. Floating or connecting to pin K only.
MS1
6
4
Mode selection pin 1. Floating or connecting to pin K only.
NC
2
-
No Connection
Exposed Thermal Pad
Exposed thermal pad of the chip. Use this pin to enhance the
power dissipation ability. The thermal conductivity will be
improved if a copper foil on PCB is soldered with the thermal pad.
It is recommended to connect the thermal pad to pin K.
Absolute Maximum Ratings
Caution: Values beyond absolute ratings can cause the device to be prematurely damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not
guaranteed.
Sustaining Voltage
A to K
-0.3V ~ 88V
CS, MS1, MS2 to K
-0.3V ~ 1V
Regulating Current
150mA
Maximum Operating Junction Temperature, TJ
165C
Operating Temperature, Topr
-40C to 110C
Storage Temperature Range
-55C to 150C
Lead Temperature (Soldering, 10 seconds)
260C
Note:
1). All voltages are with respect to Ground. Currents are positive into, negative out of the specified terminal.
2). All parameters having Min/Max specifications are guaranteed. Typical values are for reference purpose only.
3). Unless otherwise noted, all tests are pulsed tests at the specified temperature, therefore: TJ = TC = TA.
Recommended Operating Conditions
Parameter
Symbol
Min
Typ
Max
Unit
Regulating Current (with Adequate Heat
Sinking) *Note
IAK
130
mA
Input Voltage*Note
VAK
3
80
V
Maximum Junction Temperature
TJ
150
C
Operating Free-Air Temperature Range
TA
-30
100
C
Note: Due to thermal dissipation consideration, the maximum LED Vf in parallel should decrease with the regulating current.
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 5
Electrical Characteristics
Unless otherwise noted, typical values are @ TA = 25oC.
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
Peak Regulating Current
*Note 1,2
IPEAK0
VAK=5V,
Mode 0
(MS1/ MS2
connected to K)
Option C1
38.4
40
41.6
mA
Option C2
63.4
66
68.6
Option C3
49.9
52
54.1
Option D1
76.8
80
83.2
Option D2
124.8
130
135.2
Option D3
99.8
104
108.2
Current Ratio of Mode
Selection
*Note 1
IPEAK0/IPEAK0
Option C1/C2/C3/D1/D2/D3,
Mode 0, VAK=5V
(MS1/ MS2 connected to K)
100
%
IPEAK1/IPEAK0
Option C1/C2/C3/D1/D2/D3,
Mode 1, VAK=5V
(MS1 open, MS2 connected to K)
75
80
85
IPEAK2/IPEAK0
Option C1/C2/C3/D1/D2/D3,
Mode 2, VAK=5V
(MS2 open, MS1 connected to K)
50
55
60
IPEAK3/IPEAK0
Option C1/C2/C3/D1/D2/D3,
Mode 3, VAK=5V
(MS1/ MS2 open)
32
35
38
Regulating Current Line
Regulation *Note 3
󰅿ILR/IPEAKx
(x=0~3)
Option C1/C2/C3/D1/D2/D3,
Mode 1~3, VAK=5V and 40V
±1
±2
%
Option C1/C2/C3/D1/D2/D3,
Mode 0, VAK=5V and 40V
-4
-8
-15
CS Pin Voltage
VCS
Option ADJ, Mode 0,
VAK=5V, with 1KΩ external
resistor between CS and K
0.26
0.27
0.28
V
CS Pin Voltage Line
Regulation*Note 4
󰅿VLR/VCS
Option ADJ,
Mode 1~3, VAK=5V and 40V
with 1KΩ external resistor
between CS and K
±1
±2
%
Option ADJ,
Mode 0, VAK=5V and 40V
with 1KΩ external resistor
between CS and K
-4
-8
-15
%
Dropout Voltage *Note 5
VDROP
Mode 0 (MS1/ MS2 connected to K)
2.8
3.8
V
Thermal Protection Trip
Temperature*Note 6
TTP
When TJ is higher than TTP, the
peak regulating current
decreases to ITP linearly.
120
130
C
Thermal Protection Mode
Regulating Current
ITP/IPEAKx
(x=0~3)
TJ = 175C
50
%
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 6
Note 1: For ADJ option, the regulating current is determined by an external resistor, REXT, connected between the CS pin and the K pin.
The mode selection function will not change the current ratio of option ADJ. To activate the line regulation function, the chip (U3)
connected in series with the LED string should be set in Mode 0 (MS1 and MS2 connected to pin K). The regulating current will
be:
IPEAK=0.27/REXT
And the maximum regulating current of second step (ex: U2 in Mode 1) should not exceed 80% of the top level (ex: U3 in Mode
0), otherwise the circuit operation might become abnormal when OTP function is activated. It is strongly recommended to set at
75%.
Note 2: The user can add an external resistor REXT between the CS pin and the K pin of U3 (Mode 0, serial connected to the LED string)
to increase the regulating current of option C1, C2, C3, D1, D2 and D3, as shown in below. For U1 ~ U2 (Mode 1 ~ Mode 3,
parallel connected to the LED string), adding an external resistor REXT between the CS pin and the K pin may cause abnormal
operation and chip damage.
For option C1/ C2/ C3, the regulating current variation ΔIPEAK/IPEAK = 6.25/REXT.
For option D1/ D2/ D3, the regulating current variation ΔIPEAK/IPEAK = 3.13/REXT.
LED
iML8683
MS1
MS2
K
CS
NC
A
REXT
Note 3: The Regulating Current Line Regulation is defined as:
For Mode 1~3: ∆LR/=(VAK=0V)-(VAK=5V)
IAK(VAK=5V) , x=1~3
For Mode 0: ∆LR/=(VAK=40V)-(VAK=5V)
IAK(VAK=5V)
Note 4: The CS Pin Voltage Line Regulation is defined as:
For Mode 1~3: ∆
LR/
=(VAK=0V)-(VAK=5V)
(VAK=5V)
For Mode 0: ∆
LR/
=(VAK=40V)-(VAK=5V)
VCS(VAK=5V)
Note 5: Dropout voltage＝VAK @ 90% × (IPEAK0 @ VAK＝5V)
Note 6: When TJ > TTP, the peak regulating current decreases linearly to around 50% at 175°C.
0
TJ
IAK
IPEAKx
TTSD
(175°C)
TTP
(130°C)
ITP
U3 (Mode 0) regulating current
Without external
resistor
With 100Ω external
resistor
Option C1
40
42.5
Option C2
66
70.1
Option C3
52
55.3
Option D1
80
82.5
Option D2
132
136.1
Option D3
104
107.3
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 7
Application Circuit
(1) 220VAC/ 10W LED Light Engine
- 3 steps, PF=0.98, THD=16%
- To pass 1KV surge test, Q1 can be changed to 800V NMOS.
C2 Option
VAC
BD
LED2
67V
60mA
Q1
iML3160
1A/ 600 NMOS
U1
iML8683-C2
(Mode 2)
U3
iML8683-C2
(Mode 0)
ZD
24V
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
LED3
67V
60mA
U2
iML8683-C2
(Mode 1)
MS1
MS2
K
CS
NC
A
Rz2
270KΩ
LED1
134V
60mA
iLED
Rz1
270KΩ
ADJ Options
VAC
BD
U1
iML8683-
ADJ
U3
iML8683-
ADJ
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
R1
7.5Ω
U2
iML8683-
ADJ
MS1
MS2
K
CS
NC
A
R2
5.1Ω
R3
3.9Ω
iLED
LED2
67V
60mA
Q1
iML3160
1A/ 600 NMOS
LED3
67V
60mA
LED1
134V
60mA
ZD
24V
Rz2
270KΩ
Rz1
270KΩ
RBL
90KΩ RBL
90KΩ
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 8
(2) 10W LED Light Engine
- 3 steps, PF=0.98, THD=16%
- To pass 1KV surge test, Q1 can be changed to 800V NMOS.
D2 Option
VAC
BD
LED2
36V
120mA
Q1
iML3160
1A/ 600 NMOS
U1
iML8683-D2
(Mode 2)
U3
iML8683-D2
(Mode 0)
ZD
18V
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
LED3
36V
120mA
U2
iML8683-D2
(Mode 1)
MS1
MS2
K
CS
NC
A
Rz2
180KΩ
LED1
72V
120mA
iLED
Rz1
180KΩ
ADJ Options
VAC
BD
U1
iML8683-
ADJ
U3
iML8683-
ADJ
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
R1
4.7Ω
U2
iML8683-
ADJ
MS1
MS2
K
CS
NC
A
R2
3.3Ω
R3
2.4Ω
iLED
Q1
iML3160
1A/ 600 NMOS
LED2
36V
120mA
ZD
18V
LED3
36V
120mA
Rz2
180KΩ
LED1
72V
120mA
Rz1
180KΩ
RBL
47KΩ RBL
47KΩ
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 9
(3) 7W Low Cost LED Light Engine
- 2 steps, PF=0.95, THD=28%
220VAC/ ADJ Options
VAC
BD
U1
iML8683-
ADJ
U2
iML8683-
ADJ
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
R1
7.5Ω
R2
5.6Ω
iLED
LED2
68V
50mA
Q1
iML3160
1A/ 600 NMOS
LED1
200V
50mA
ZD
24V
Rz2
270KΩ
Rz1
270KΩ
RBL1
68KΩ
120VAC/ ADJ Options
VAC
BD
U1
iML8683-
ADJ
U2
iML8683-
ADJ
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
R1
3.9Ω
R2
3.0Ω
iLED
LED2
36V
90mA
Q1
iML3160
1A/ 600 NMOS
LED1
108V
90mA
ZD
18V
Rz2
180KΩ
Rz1
180KΩ
RBL
68KΩ
RBL2
68KΩ
(4) Low Flicker Solution
VAC
BD
U1
iML8683-
ADJ
LED1
U3
iML8683-
ADJ
Rz2
ZD
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
U2
iML8683-
ADJ
MS1
MS2
K
CS
NC
A
R2
R1
R3
D1
80V
CV
RBL1
LED2
LED3
Rz1
RBL2
3-Step/ ADJ Options
Q1
iML3160
1A/ 600 NMOS
VAC
BD
U1
iML8683-
ADJ
LED1
U2
iML8683-
ADJ
Rz2
ZD
MS1
MS2
K
CS
NC
A
MS1
MS2
K
CS
NC
A
R1
R2
D1
80V
CV
LED2
Rz1
2-Step/ ADJ Options
Q1
iML3160
1A/ 600 NMOS
RBL1
RBL2
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 10
Package Information
DFN– 2mmx2mm– 6L
E
D
A
A1
A3
e
b
E1
1
L
D1
K
Footprint Suggestion
Y
X
B A
C
D
P
SYMBOLS
MIN.
NOM.
MAX.
A
0.70
0.75
0.80
A1
0.00
0.02
0.05
A3
-
0.20
-
b
0.20
0.30
0.35
D
-
2.00
-
D1
-
1.20
-
E
-
2.00
-
E1
-
0.70
-
e
-
0.65
-
K
0.20
-
-
L
-
0.30
-
UNIT: MILLIMETERS
SYMBOLS
Footprint
Dimension
A
2.80
B
1.20
C
0.80
D
0.35
P
0.65
X
1.40
Y
0.70
JA
103 C / W
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 11
SOT-89-5L
SYMBOLS
MIN.
MAX.
A
1.40
1.60
b
0.32
0.52
b1
0.36
0.56
c
0.35
0.44
D
4.40
4.60
D1
1.40
1.80
E
2.30
2.60
E1
3.94
4.25
e
1.50 TYP
e1
2.90
3.10
L
0.90
1.10
UNIT: MILLIMETERS
Footprint Suggestion
D1
D2
A
D
M
P2
C
P1
C
BB1 D
θ
B2
θ
JA
127.5 C / W
SYMBOLS
Footprint
Dimension
A
5.20
B
4.80
B1
3.60
B2
0.25
C
1.35
D
0.70
D1
1.90
D2
1.30
M
3.70
P1
1.50
P2
3.00
θ
45°
UNIT: MILLIMETERS
iML8683
Three Terminal Current Controller
© 2014 Exar Corporation 8683DOC rev 1.2 12
Records of Revisions
Rev.
Date
Page
Description
1.0
Feb. 7, 2014
All
First release.
1.1
Mar. 6, 2014
1, 2, 3, 11
Remove package types of TO-252.
1.2
Nov. 21, 2014
3
Update the Block Diagram and I-V Curve.
5, 6
Update the TTP Range and Notes.
7, 8, 9
Update the Application Circuits.
10, 11
Udate the Package Dimension and Footprint Suggestion.
12
Add Records of Revision