AL1696

AL1696
HIGHLY INTEGRATION OFFLINE DIMMABLE LED DRIVER
Description
Pin Assignments
NEW PRODUCT
The AL1696 is a highly integrated high power factor constant current
converter for mains dimmable LED driver applications. The AL1696
controls the system operating in boundary conduction mode (BCM) to
ease in EMI/EMC qualification and testing to meet the latest
regulatory standards.
(Top View)
The AL1696 with build-in MOSFET solution reduces the bill of
material (BOM) cost by eliminating the need of auxiliary winding and
external high voltage MOSFET.
The AL1696 can be compatible with a wide range of dimmers
including leading edge and trailing edge dimmers. Some dimmers can
achieve deep dimming down to 1%. The AL1696 dimming curve is
compliant with the standard of NEMA SSL6.
The AL1696 is available in SO-7 package, which provides an extra
pin spacing between the high voltage MOSFET’s drain and low
voltage pins to increase electricity isolation.
7
D
3
6
VCC
4
5
RT
NC
1
NC
2
CS
GND
SO-7
Applications


Mains Dimmable LED Lamps
Offline LED Power Supply Driver
Features


Internal MOSFET up to 300V/3A, 500V/2A, 600V/2A
Tight Current Sense Tolerance: ±3%






Low Startup Current: 150µA
Low Operation Current: 120µA (Switching Frequency at 5kHz)
Single Winding Inductor
Wide Range of Dimmer Compatibility
Dimming Curve Compliant with NEMA SSL6
Internal Protections
 Under Voltage Lockout (UVLO)
 Leading-Edge Blanking (LEB)
 Cycle-by-cycle Over Current Protection (OCP)
 Output Short Protection (OSP)
 Over-Temperature Protection (OTP)

SO-7 Package

Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)

Halogen and Antimony Free. “Green” Device (Note 3)
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
AL1696
Document number: DS38304 Rev. 1 - 2
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AL1696
Typical Applications Circuit
L1
FR1
DB1
R1
C3
NEW PRODUCT
C1
R5
C2
1
NC
2
CS
3
GND
4
R2
D
7
U1 AL1696
AC
Input
NC
R3
6
VCC
5
RT
C4
D1
R6
R4
R7
+
L2
D2
C5
LEDS
Buck-Boost Application Circuit
L1
DB1
R1
C3
C1
R5
C2
1
NC
2
CS
3
GND
4
7
U1 AL1696
AC
Input
NC
R2
D
R3
6
VCC
5
RT
C4
R4
R6
D2
L2
D1
R7
+
FR1
C5
LEDS
Buck Application Circuit
Pin Descriptions
Pin Number
Pin Name
1, 2
NC
No connection
3
CS
Current sensing
4
GND
5
RT
6
VCC
7
D
AL1696
Document number: DS38304 Rev. 1 - 2
Function
Ground
Resistor set the system’s maximum tON
Power supply voltage
Drain of the internal high voltage MOSFET
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AL1696
Functional Block Diagram
VCC
STOP
OFF
Fault
Management
VCC
Management
UVLO
VDD
NEW PRODUCT
OSP
VRT_REF
Set tON_MAX
VCC
1, 2
Q
OCP
tON_MAX
AL1696
Document number: DS38304 Rev. 1 - 2
CS
tOFF
Driver Supply
Clamp
S
4
VREF
tOFF Detection
(ZCD)
R
GND
3
VCC
Clamp
OSP
5
tON_MAX
NC
D
OTP
VRT_REF
RT
7
6
+
-
LEB
VREF
STOP
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AL1696
Absolute Maximum Ratings (@TA = +25°C, unless otherwise specified.) (Note 4)
Symbol
VCC
NEW PRODUCT
VD
ID
Rating
Unit
Power Supply Voltage
18
V
Voltage on D Pin (AL1696-30AS7-13)
300
V
Voltage on D Pin (AL1696-20BS7-13)
500
V
Voltage on D Pin (AL1696-20CS7-13)
600
V
Continuous Drain Current TC = +25°C (AL1696-30AS7-13)
3.0
A
Continuous Drain Current TC = +25°C (AL1696-20BS7-13)
2.0
A
Parameter
Continuous Drain Current TC = +25°C (AL1696-20CS7-13)
2.0
A
VCS
Voltage on CS Pin
-0.3 to 7
V
VRT
Voltage on RT Pin
-0.3 to 7
V
TJ
Operating Junction Temperature
-40 to +150
°C
TSTG
Storage Temperature
-65 to +150
°C
TLEAD
Lead Temperature (Soldering, 10 seconds)
+260
°C
PD
Power Dissipation and Thermal Characteristics (TA = +50°C)
0.8
W
JA
Thermal Resistance (Junction to Ambient) (Note 5)
123
°C/W
JC
Thermal Resistance (Junction to Case) (Note 5)
19
°C/W
2,000
V
200
V
–
Notes:
ESD (Human Body Model)
ESD (Machine Model)
4. Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “Recommended Operating Conditions” is not implied.
Exposure to “Absolute Maximum Ratings” for extended periods may affect device reliability.
5. Device mounted on 1"x1" FR-4 substrate PCB, 2oz copper, with minimum recommended pad layout.
Recommended Operating Conditions (@TA = +25°C, unless otherwise specified.)
Symbol
TA (Note 6)
Note:
Parameter
Ambient Temperature
Min
Max
Unit
-40
+105
°C
6. The device can operate normally at +125°C ambient temperature under the condition that the junction temperature is less than +150°C.
AL1696
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AL1696
Electrical Characteristics (@TA = +25°C, unless otherwise specified.)
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
UVLO
Startup Voltage
–
–
14.5
–
V
Minimal Operating Voltage
After Turn On
–
8.5
–
V
VCC Clamp Voltage
ICC = 1mA
–
16
–
V
–
150
–
µA
Switching Frequency at
5kHz
–
120
–
µA
AL1696-30A
–
–
3
Ω
AL1696-20B
–
–
6
Ω
AL1696-20C
–
–
5.5
Ω
AL1696-30A
–
–
3.0
A
AL1696-20B
–
–
2.0
A
AL1696-20C
–
–
2.0
A
AL1696-30A
300
–
–
V
AL1696-20B
500
–
–
V
AL1696-20C
600
–
–
V
AL1696-30A
@VDS = 300V, VGS = 0V
–
–
1
µA
AL1696-20B
@VDS = 500V, VGS = 0V
–
–
1
µA
AL1696-20C
@VDS = 600V, VGS = 0V
–
–
1
µA
Reference Voltage of RT Pin
–
–
0.5
–
V
Current Sense Reference
–
0.388
0.400
0.412
V
tON_MIN
Minimum tON
–
–
550
–
ns
tON_MAX
Maximum tON
RT = 27kΩ
–
8
–
µs
tOFF_MAX
Maximum tOFF
–
–
180
–
µs
tOFF_MIN
Minimum tOFF (Note 7)
–
–
6
–
µs
–
–
+170
–
°C
VTH(ST)
VOPR(min)
NEW PRODUCT
VCC_CLAMP
Standby Current
IST
ICC(OPR)
VCC = VTH(ST)-0.5V,
Start-Up Current
Before Start Up
Operating Current
Internal High Voltage MOSFET
RDS(ON)
IDS
VDS
IDSS
Drain-Source On-State Resistance
Continuous Drain-Source Current
Drain-Source Breakdown Voltage
Drain-Source Leakage Current
RT
VRT
Current Sense
VREF
Over Temperature Protection
–
Notes:
Shutdown Temperature (Notes 7 & 8)
7. These parameters, although guaranteed by design, are not 100% tested in production.
8. The device will latch when OTP happen and the device won’t operate constantly at this temperature.
AL1696
Document number: DS38304 Rev. 1 - 2
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AL1696
Performance Characteristics (Note 9)
Start-up Voltage vs. Ambient Temperature
Start-up Current vs. Ambient Temperature
16.0
180
15.5
170
Start-up Current (A)
Start-up Voltage (V)
14.5
14.0
13.5
13.0
12.0
-40
160
150
140
130
12.5
-20
0
20
40
60
80
100
120
120
-40
o
-20
0
Ambient Temperature ( C)
60
80
100
120
Operating Current vs. Ambient Temperature
140
9.5
130
9.0
Operating Current (A)
Minimal Operating Voltage (V)
40
o
10.0
8.5
8.0
7.5
7.0
120
110
100
90
80
6.5
6.0
-40
20
Ambient Temperature ( C)
Minimal Operating Voltage vs. Ambient Temperature
-20
0
20
40
60
80
100
70
-40
120
-20
0
20
40
60
80
100
120
o
Ambient Temperature ( C)
o
Ambient Temperature ( C)
VCS Reference vs. Ambient Temperature
VRT Reference vs. Ambient Temperature
0.50
0.60
0.45
0.55
0.40
0.50
VRT Reference (V)
VCS Reference (V)
NEW PRODUCT
15.0
0.35
0.30
0.40
0.35
0.25
0.20
-40
0.45
-20
0
20
40
60
80
100
120
0.30
-40
o
AL1696
Document number: DS38304 Rev. 1 - 2
-20
0
20
40
60
80
100
120
o
Ambient Temperature ( C)
Ambient Temperature ( C)
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AL1696
Performance Characteristics (Cont.) (Note 9)
VCC Clamp Voltage vs. Ambient Temperature
24
VCC Clamp Voltage (V)
NEW PRODUCT
21
18
15
12
9
6
-40
-20
0
20
40
60
80
100
120
o
Ambient Temperature ( C)
Note:
9. These electrical characteristics are tested under DC condition. The ambient temperature is equal to the junction temperature of the device.
AL1696
Document number: DS38304 Rev. 1 - 2
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AL1696
Functional Description and Application Information
Convertor Operation
The AL1696 internal MOSFET’s on time is limited by tON_MAX which is set through RT pin and internal 0.4V reference. The MOSFET will be turned
off either its on time triggers tON_MAX or input voltage on CS pin triggers internal 0.4V reference voltage. So if the tON_MAX is set to a very small
value, the system will operate in constant on-time (tON_MAX) mode during the whole rectified mains cycle. It will result in a good power factor, but
the line regulation will be worse. Normally, a recommended tON_MAX should make the system operate in constant on-time (tON_MAX) mode at valley
of input voltage and peak current mode at the crest. A trade off between PF and line regulation need to be done when setting tON_MAX.
The AL1696 adopts source-driver technology to decrease the system operating current. Besides, it uses a novel tOFF time detection method
without auxiliary winding. The AL1696 operates in boundary conduction mode (BCM) which can ease EMI design. All of them help AL1696 to have
an extremely low bill of material (BOM).
L1
FR1
NC
DB1
R1
C3
C1
C2
R5
1
NC
2
CS
3
GND
4
7
U1 AL1696
AC
Input
R2
D
R3
6
VCC
5
RT
C4
D1
R6
R4
L2
D2
R7
+
NEW PRODUCT
The AL1696 is a single stage, single winding inductor, high efficiency, and high power factor LED driver solution for mains input phase-cutting
dimmable application. It is available for three internal MOSFET options (300V/3A, 500V/2A and 600V/2A) which helps to reduce the overall LED
driver solution’s size and optimize bom cost. The three different MOSFET options can cover most of 3~12W dimmable applications.
C5
LEDS
Figure 1. Typical Buck-Boost Application Circuit
Start-up and Supply Voltage
During start-up, the VCC capacitor C4 is charged through startup resistors (R2, R3) from the rectified mains input until the start-up voltage is
reached, the AL1696 starts switching. In normal operation, the VCC supply is provided from two paths: one is from start-up resisters (R2, R3) and
the other is from output voltage (VOUT) through one diode (D2). In this way the system can provide sufficient VCC supply at low dimming angle.
The AL1696 has internal VCC clamp, the typical voltage is 16V. VCC voltage needs to be between VOPR(min) and VCC_CLAMP during normal
operation.
When VCC voltage drops below the under voltage lockout (UVLO), IC will stop switching. The IC will restart once the voltage on VCC pin exceeds
the startup voltage (VTH(ST)) again.
Protections
Under Voltage Lockout (UVLO)
When the voltage on the VCC pin drops below VOPR(Min), the IC will stop switching. The IC will restart until the VCC voltage exceeds the startup
voltage (VTH (ST)) again.
Leading-Edge Blanking (LEB)
To prevent false detection of the peak current through MOSFET, a blanking time following switch-on is designed. When the internal switch turns
on, a short current spike may appear because of the discharge of the parasitic capacitor over MOSFET’s drain and source. It will be ignored
during the LEB time (tON_MIN).
Cycle-by-cycle Over Current Protection (OCP)
The AL1696 has a built-in peak current detector. The R5 connected to the CS pin is used to sense the current through MOSFET and will be one of
the inputs. The detection circuit is activated after the LEB time. When the voltage on CS pin reaches VREF, the IC will turn off the switch to limit the
output current.
AL1696
Document number: DS38304 Rev. 1 - 2
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AL1696
Functional Description and Application Information (Cont.)
The peak current (IPEAK) of the MOSFET can be set as below:
VREF
R5
I PEAK 
NEW PRODUCT
It automatically provides a cycle-by-cycle protection of maximum current through MOSFET during operation. A propagation delay exists between
over current detection and actual source-switch off, so the actual peak current will be a little higher than the OCP level set by R5.
Output-Short Protection (OSP)
When LED is shorted, the device can’t detect the tOFF time, and the system will work with low switching frequency of 5kHz.
Over-Temperature Protection (OTP)
The AL1696 has OTP protection function. When the junction temperature reaches +170°C typical, it will trigger an over-temperature protection
which makes IC shut down and latched. Once OTP is triggered, the system will only restart after the system’s power supply powers off and on
again.
Design Parameters based on buck-boost topology
Setting the Current Sense Resistor R5
In AL1696 typical application, a tON_MAX is recommended to make the system operate at constant on-time (tON_MAX) mode at valley of input
voltage and peak current mode at the crest. In most of cases, the tON_MAX will set to be 1.3 times of the tON at crest, and the critical angle of two
operation modes will be:
 1 

 1.3 
  a sin 
Then the output current can be calculated as below:
I O _ MEAN 

 

2VIN _ RMS sin( )
2VIN _ RMS sin( )
2VIN _ RMS sin( )
VREF
(  1.3  sin( )
dt  
dt +  1.3  sin( )
dt )
2  R5 0
2VIN _ RMS sin( )  VO
2VIN _ RMS sin( )  VO
2VIN _ RMS sin( )  VO

 
Where,
VREF is the internal reference, typical 0.4V.
R5 is the current sense resistor.
VIN_RMS is the input voltage’s RMS value.
VO is the system output voltage.
Inductance Selection (L2)
The peak current of the MOSFET is calculated as below:
I PEAK 
VREF
R5
The AL1696 is operating in boundary conduction mode which results in a variable operating frequency. The minimum switching frequency fMIN
should be set at the crest of the minimum AC input voltage. Inductance should be calculated according to the chosen fMIN:
L2 
2VIN _ RMS VO
I PEAK (
 2VIN _ RMS +VO) f MIN
According to the Faraday’s Law of Induction, the winding number of the inductance can be calculated by:
AL1696
Document number: DS38304 Rev. 1 - 2
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AL1696
Functional Description and Application information (Cont.)
NL2 
L 2  I PEAK
Ae  Bm
Where,
NEW PRODUCT
Ae is the core effective area.
Bm is the maximum magnetic flux density.
tON_MAX Setting
In order to get a high power factor and good dimmer compatibility, the system should operate in constant on time mode at valley of input voltage. It
can be realized by setting the maximum on time, which is set by on external resistor connect to RT pin.
And the tON time has the below equation:
tON _ MAX 
25  C REF  R 6
VRT _ REF
Where,
VRT_REF is the internal RT pin 0.5V’s reference.
CREF is the internal 6pF capacitor.
Dimmer Compatibility
Passive Bleeder Design
The passive bleeder is designed to supply latching and holding current to get rid of dimmer’s misfire and flicker.
L
FR1
Passive
Bleeder
L1
Damping
DB1
R1
C1
N
DB1
C2
Figure 2. LED Driver Schematic with Passive Bleeder
The passive bleeder includes a capacitor (C2, in hundreds of nF) to provide latching current and a resistor (R1) to limit the current spike. Because
a large C2 will affect the PF, THD and efficiency negatively, the value of the capacitor (C2) should be selected carefully. Generally, a capacitance
from 100nF/400V to 330nF/400V is recommended. R1 is used to limit the latching current. If R1 is too big, the latching current will be not enough
and the TRIAC dimmer will be misfired, resulting in LED flicker. If R1 is too small, it will result in greater power dissipation. Generally, a 200Ω to
2KΩ resistor is recommended for R1.
Passive Damping Design
FR1 is to limit the spike current caused by quick charging of C2 when dimmer on. Normally, FR1 will be chosen from 20Ω to 100Ω for low line like
120VAC application, and 51Ω to 200Ω for high line like 230VAC application.
AL1696
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AL1696
Ordering Information
AL1696–XX X XX–13
NEW PRODUCT
Current Option
MOSFET Voltage
Package
A: 300V
B: 500V
C: 600V
S7 : SO-7
20 : 2.0A
30 : 3.0A
Part Number
Package Code
Package
AL1696-30AS7-13
S7
AL1696-20BS7-13
AL1696-20CS7-13
Packing
13 :13" Tape & Reel
13” Tape and Reel
Quantity
Part Number Suffix
SO-7
4000/Tape & Reel
-13
S7
SO-7
4000/Tape & Reel
-13
S7
SO-7
4000/Tape & Reel
-13
Marking Information
(Top View)
7
6
5
Logo
Part Number
1696-30A for 3.0A/300V
1696-20B for 2.0A/500V
1696-20C for 2.0A/600V
1696 - ZZZ
YY WW X X
1
AL1696
Document number: DS38304 Rev. 1 - 2
YY : Year : 15,16,17 ~
WW : Week : 01~52; 52
represents 52 and 53 week
X X : Internal Code
2
3
4
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AL1696
Package Outline Dimensions (All dimensions in mm.)
(1)
Package Type: SO-7
5.800(0.228)
1.350(0.053)
1.750(0.069)
NEW PRODUCT
6.200(0.244)
0.330(0.013)
0.510(0.020)
2.54(0.100)
TYP
4.700(0.185)
5.100(0.201)
1.270(0.050)
TYP
0.080(0.003)
0.250(0.010)
3.800(0.150)
4.000(0.157)
1.250(0.049)
1.500(0.059)
0.350(0.014)
TYP
0°
8°
Option 1
0.450(0.017)
0.800(0.031)
45°
0.150(0.006)
0.250(0.010)
Option 2
Note: Eject hole, oriented hole and mold mark is optional.
AL1696
Document number: DS38304 Rev. 1 - 2
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AL1696
Suggested Pad Layout
Package Type: SO-7
NEW PRODUCT
(1)
G
Z
E1
Y
X
E
Dimensions
Z
(mm)/(inch)
G
(mm)/(inch)
X
(mm)/(inch)
Y
(mm)/(inch)
E
(mm)/(inch)
E1
(mm)/(inch)
Value
6.900/0.272
3.900/0.154
0.650/0.026
1.500/0.059
1.270/0.050
2.540/0.100
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AL1696
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INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
(AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION).
NEW PRODUCT
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final and determinative format released by Diodes Incorporated.
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written approval of the Chief Executive Officer of Diodes Incorporated. As used herein:
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1. are intended to implant into the body, or
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