STMICROELECTRONICS EFS21-TL5

EFS

STARLIGHT-KIT
Application Specific Discretes
2-CHIPS SET FOR FLUORESCENT LAMP STARTER
A.S.D.
FEATURES
n
n
n
n
n
n
n
VERY WIDE TEMPERATURE RANGE:
tube ignition from - 30 to + 85 °C
SINGLE SHOT IGNITION FROM -30 to 0°C :
350mA, 1350V striking pulse
VERY WIDE POWER RANGE:
Fluorescent tube lamp ignition from 18 to 70W
EFS2B driver compatible with 50/60Hz
operation
SELECTABLE PREHEAT TIME:
EFS2A driver: 1.5s or 2.56s (50Hz)
EFS2B driver: 0.74s or 1.24s (50Hz)
EFS2B driver: 0.62s or 1.03s (60Hz)
8 STRIKING PULSES CAPABILITY:
for very cold environment or ageing lamp
STARTER SHUTDOWN WITH FAILED LAMP
S014
EFS2A-CD
EFS2B-CD
BENEFITS
n
n
n
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Very low component count: 2 chips + 7 passive
components
Meet EN55015 standards WITHOUT EMI
capacitor
Extended life time of the fluorescent lamp due to
smooth and single shot ignition
High inherent reliability and extended life time
of the starter
PENTAWATT HV
EFS21-TL5
DESCRIPTION
The EFS Kit is a 2 chips set used with 7 additional
passive components, for Glow switch Starter.
The ASD (Application Specific Discretes)
includes a bi-directional Power Switch and a
Power Supply for the driver.
The driver provides a program to ensure a fully
optimised linear fluorescent lamp ignition.
TM : ASD is trademark of STMicroelectronics.
May 2000 - Ed: 5A
1/14
EFS
PIN CONNECTION (top view)
SO14
State tube detection
Preheat select
to be grounded
Shunt
to be grounded
to be grounded
to be grounded
1
2
3
4
5
6
7
Pentawatt HV
14
13
12
11
10
9
8
G1
G2
VCC
GND
to be grounded
DO NOT CONNECT
to be grounded
G1
Vcc
1
2
Tube
3
GND
G2
4
5
DRIVER: EFS2A-CD
and
: EFS2B-CD
ASD: EFS21-TL5
EFS STARLIGHT-KIT PARTS SELECTION:
The EFS STARLIGHT-KIT answers effectively to linear fluorescent lamp ignition needs:
MAINS FREQUENCY
50Hz
DRIVER VERSION
60Hz
EFS2A
EFS2B
Pin 2 connection
GND
VCC
GND
VCC
GND
VCC
PREHEAT DURATION
1.5s
2.56s
0.74s
1.24s
0.62s
1.03s
ASD
EFS21
LAMP POWER RANGE
18 to 70W (note 2)
AMBIENT TEMPERATURE RANGE
-30 to 85°C (note1, note 2)
Note 1: below -20°C, it is recommended to limit the lamp power range to 58W.
Note 2: the ignition temperature range is given with starting aid, as required in the IEC 81 and IEC 926 (§6.3.1) standards.
BASIC APPLICATION DIAGRAM
BALLAST
150KΩ
ASD
DRIVER
MAINS
FLUORESCENT
LAMP
4
18W TO 70W
U2
DO NOT
CONNECT
14
1
3
13
5
U1
12
2
9
4
R
7/8/10/11
2/3/5/6
0.39Ω
2/14
1
22µF - 16V
EFS
RECOMMENDED LAMP POWER RANGE APPLICATION
LAMP POWER (W)
70 W
58 W
WORKING AREA
36 W
18 W
-30
-20
-10
0
10
20
30
40
Tamb (°C)
50
60
70
80
90
(see note 2)
Note 2: the ignition temperature range is given with starting aid, as required in the IEC 81 and IEC 926 (§6.3.1) standards.
ABSOLUTE RATINGS (limiting values)
Symbol
Parameter
Value
Unit
Top
Operating Junction temperature range
-30 to +125
°C
Tstg
Storage temperature range
-55 to +150
°C
Value
Unit
14
V
500
mW
1
kV
±10
V
Parameter
Value
Unit
Tcase = 90°C
1
A
+ 120
°C
DRIVER: EFS2 A & EFS2B
Symbol
Parameter
Vcc
Maximum supply voltage
Ptot
Power dissipation
ESD
Electrostatic discharge between any pins
Standard: MIL STD 883C Human Body Model
VSENSE
Input operating range
ASD: EFS21
Symbol
IT(RMS)
RMS on-state current
Tcase
IT(RMS) = 1A
tOFF = 0.16s
tON = 0.75s
ITSM
Surge peak on-state current
Tj initial = 25°C, tp = 10ms
Minimum repetitive rate periode : 1min.
15
A
VDRM
VRRM
Repetitive peak off-state voltage
600
V
3/14
EFS
ELECTRICAL CHARACTERISTICS (Tj = 25°C, unless otherwise specified)
DRIVER
Symbol
Parameter
Min.
Typ.
Max.
Unit
12
V
5
V
Vcc
Supply voltage in preheat mode
VUVLO
Under voltage lock-out threshold
VCCH
Supply limitation high in standby mode
6.8
7.7
8.7
V
VCCL
Supply limitation low in standby mode
6.77
7.57
8.41
V
ICC
Supply current in standby mode
440
450
475
µA
ISO
Ignition current level Rsense = 0.39Ω
280
350
420
mA
7
LAMP OFF STATE DETECTION
tc
VREF
Checking delay after zero crossing lamp voltage
EFS2A version
2.9
5.9
ms
EFS2B version
2.5
7.5
ms
Internal reference voltage
1.12
1.26
V
Typ.
Max.
Unit
ASD
Symbol
Parameter
Min.
VT +
Positive on-state voltage
IT = 1.5A
tp = 500µs
2.1
3.15
V
VT -
Negative on-state voltage
IT = 1.5A
tp = 500µs
0.89
1.2
V
VBR
Breakdown positive voltage IDRM = 5mA
1350
1500
V
tp = 10ms
VDCM
VRCM
Non repetitive peak off-state voltage
Pin 1 = Pin 2 = Pin 4 = Pin 5 Repetitive rate : 3Hz
IDRM
IRRM
Leakage current, at VDRM/VRRM rated
Pin 1 = Pin 2 = Pin 4 = Pin 5
IH
1200
800
V
20
Holding current dI/dt = 9 A/ms
Pin1 = Pin 2 = Pin4 = Pin5
350
µA
mA
ORDERING INFORMATION
DRIVER
EFS
Electronic
Fluorescent
Switch
4/14
2
Kit
A/B
Version
Digit
A: 50Hz
B: 50/60Hz
ASD
-
CD
SO14
Package
EFS
Electronic
Fluorescent
Switch
2
Kit
TM
1
Version
Digit
-
TL5
TL5:
Pentawatt HV Package
with lead forming
EFS
DEMONSTRATION BOARD DIAGRAM
THERMAL
FUSE
R1
R2
D1
R4
R3
DRIVER
4
4
U2
R6
ASD
14
1
3
13
5
U1
12
2
4
Vcc
9
OPEN
one of the tracks
2
7/8/10/11
3/5/6
C1
GND
R5
When the starter has to be protected against over-temperature, over-current or short circuit, it is
recommended to implement a thermal fuse in series with the starter.
To meet (IEC 926) standards, a capacitor (f.i. 5nF) can be connected between pin 3 and pin 4 of the ASD.
BOARD ASSEMBLY
PCB with Pentawatt HV and SO14
DRILL and CUT the track
for SHORT preheat -->
for LONG preheat -->
Pin 2 is the preheat time select pin. To select a short preheat time, drill to cut the Vcc to pin 2 track at the
metallic hole. To select a long preheat time, drill to cut the GND to pin 2 track. The layout must be
configured for either choice to avoid supply short circuit.
RECOMMENDED COMPONENTS ACCORDING TO APPLICATION CONDITIONS
Application Conditions
AC mains
Lamp Power Range
Single
230V - 50Hz
Single
120V - 60Hz
Twin series 230V / 50Hz or
single 115V / 50Hz
18 to 70W
Ambient Temperature Range
18 to 36W
-30 to + 85°C (note 3)
Recommended Components
ASD version
Driver version
R1, R2
EFS21
EFS2A or EFS2B
30kΩ - 0.125W - 5%
R3
R4
EFS2B
EFS2A or EFS2B
15kΩ - 0.125W - 5%
130kΩ - 0.125W - 5%
2.2kΩ - 0.25W - 5%
3.3kΩ - 0.25W - 5%
R5
0.39Ω - 0.25W - 5% (note 4)
R6
0.39kΩ - 0.25W - 5%
C1
22µF - 16V - 20%
C2
BYD17K (800V)
Note 3: below -20°C, it is recommended to limit the lamp power range to 58W.
Note 4: R5(Rsense) should have a 8 A, 10 ms surge capability.
5/14
EFS
EFS STARLIGHT-KIT APPLICATION NOTE
1/ THE AC POWER SWITCH: FUNCTIONAL DESCRIPTION
he Starter is a bi-directional switch which performs two functions:
the preheat of the tube,
the ignition of the tube.
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BALLAST
PREHEAT
1
FLUORESCENT
TUBE
2
V strike
3
220V / 50HZ
The mains voltage is applied
Preheating of the tube
During the preheat period, the ASD is fully
conducting. The tube lamp is short circuited by the
starter, and the current flows through its filaments.
In these conditions, the lamp can not light up, but
the temperature of the lamp electrodes increases.
At the end of the preheat period, lamp filaments
are warm enough to emit electrons in the gas and
to permit the lamp ignition in good conditions. The
ASD switches off the preheating current . At this
moment, the ballast is equivalent to a current
generator (I=ISO, ISO = Switched Off current). As
the ASD switches off, the starter voltage
increases. The amplitude of this high voltage spike
is then clamped by the ASD (VBR′1350 V). As
the starter and the lamp are in parallel, the striking
pulse is directly applied to the lamp. The
electromagnetic energy of the ballast is then
discharged through the lamp and the ASD.
Striking pulse
2/ WHAT’S NEW IN THIS SWITCH?
NEW EFS ASD
The AC SWITCH merges an auxiliary power
supply for the driver, a power clamping device
(1350V) and a bi-directional switch with his
execution pilot block.
Striking of the tube
TUBE
Vcc
Power supply
GND
6/14
HIGH
VOLTAGE
ON / OFF
DRIVER
CLAMPING
G2
AC SWITCH
G1
EFS
Present solutions work with a unidirectional
switch, like MOS transistors or GTO (Gate Turn
Off thyristor). As a starter is a bi-directional switch,
it is necessary to use a rectifier bridge (4 diodes of
1500V ). More, 2 or 3 diodes in series with the
GTO are required to get the necessary switch off
effect, and the whole is controlled with an analog
timer built around a small SCR.
The interest of a bi-directional switch arises itself:
a drastic reduction of the number of components,
and of course, a reduction of power losses (only 1
forward voltage instead of 5).
Conventional discrete circuit (minimal version)
1500V
GTO
SCR
3/ LAMP IGNITION FEATURE:
A lamp requires a minimum energy level to be ignited, but this energy depends especially on the lamp
temperature. The lower the temperature is, the more energetic the lamp strike is.
L.I SO 2
This energy stored in the ballast is directly proportional to the Switched Off current I SO (E =
).
2
In other words, the required energy and of course the ISO level, are maximum for the minimum
temperature. Results based on experiments show that it is necessary to switch off a current of 350 mA to
strike a 58W tube at -30°C (with a voltage amplitude clamped at 1200V and starting aid).
Therefore, the best way to strike a tube independently of the temperature is to keep the maximum ISO level
for all the temperature range. Unfortunately, the solution is not so simple to implement because the energy
level at ambient or warm temperature would be much important: the lamp would be ignited, but the lamp
lifetime would be shortened. This is why one of the innovations of the ASD is to modulate the striking
energy versus temperature (see feature hereafter).
I.S.O.
350mA
Switched off current
versus ambient temperature
200mA
A.S.D. FEATURE
For freezing temperatures, the ISO level is maintained at 350 mA, and for positive temperatures, the ISO
level decreases slowly.
7/14
EFS
4/ AUXILIARY POWER SUPPLY:
In order to reduce the number of components, an
auxiliary power supply is integrated in the ASD.
This active power supply works directly on the
mains and requires only a low voltage capacitor
16V - 22µF. The operating mode of this supply
varies with the starter operating phase:
POWER SUPPLY SCHEMATIC
R2
D1
R1
ASD
TUBE
R6
DRIVER
G1
7.68
VCC
7.57
C SUPPLY
GND
Supply operation during preheat phase:
During preheat phase, the driver manages alone the supply function (neither the driver nor D1 and R6 are
involved). A part of the current flowing through the ASD is used, at the beginning and at the end of each
positive mains half cycle, to charge the output capacitor.
Supply operation during standby phase:
When the lamp is lit, the monitors its supply voltage (Vcc). At the beginning of each positive mains half
cycle, when Vcc is lower than 7.57V, the driver closes the ASD supply switch. The capacitor is charged
to provide the standby current of the driver. During this phase the tube lamp is short circuited by the
ASD. When the supply voltage reaches 7.68V, the driver opens the ASD supply switch. Since this
current is also flowing in the ballast, the supply turn off provides across the lamp an additional voltage
spike. After running few minutes the lamp becomes warm and this spike voltage naturally decreases.
SUPPLY DURING PREHEAT PHASE
SUPPLY DURING STANDBY PHASE
(Without E.M.I. Capacitor nor R6 nor D1)
Starter current
at the ignition
5min after
ignition
Starter voltage
To reduce dramatically this repetitive voltage spikes across the lamp, the R6 resistor with the diode D1
provide a part of the supply current. Thus, the ripple voltage of the supply voltage is reduced, as well as the
level of the switched off current. On the other hand, this increases the safety margin of the RF noise
(versus the IEC 55015 limits)
8/14
EFS
5/ THE DRIVER: FUNCTIONAL DESCRIPTION
EFS2A DRIVER Internal block diagram (50Hz operation)
State
tube
State tube detection
(Striked / Off)
Shunt
Clock 1/8
0 current synchro
ISO synchro
350mA
8 attempts
Strikes counter
Pre-heat
period
counter
1,5s
or
2.5s
Current generator
30mA
Preheat
Select
G2
UVLO
G1
Vcc
Minimum
Power supply
GND
ALGORITHM
1. At switch on:
At switch on, an integrated Under Voltage Lock Out function (UVLO) resets the driver as long as the supply
voltage stays below a safety level.
2. Preheat:
AC MAINS ON
The ignition sequence begins with the preheat
UVLO
RESET
phase. Two different duration’s can be selected with
PIN 2 (see table EFS STARLIGHT-KIT PARTS
Preheat *
1.5s or 2.5s
SELECTION page 2).
During this phase, the driver maintains the ASD in
a full ON-state making the starter equivalent to a
Strike
bi-directional conducting switch.
3. Ignition of the fluorescent tube:
Attempt = Attempt + 1
At the end of the preheat period, the starter strikes
Preheat *
0.75s or 1.25s
the fluorescent lamp.
Loop 2
Tube
YES
For that, the driver reads continuously the current
YES
Loop 3
Ignited?
through the starter. When the current reaches the
NO
Attempt <8
Autosupply
Switch Off level (ISO = 350mA), the driver turns off
Fail = Fail + 1
the ASD. This induces a high voltage pulse across
NO
Loop
1
the lamp. This pulse amplitude is limited by the
Fail = 0
Fail = 8
ASD (′1350V).
NO
Attempt = 0
4. If the lamp fails to strike:
YES
Autosupply
Fail
=0
The driver detects the state of the tube (lit or off). If it
stays off during 8 mains cycles (loop 1), a new
preheat period, shorter than the first one, starts
* see the preheat duration table § 6
again (loop 3), followed by a new ignition attempt.
The driver will try to fire the tube 8 times. If none of
the 8 attempts succeeds in striking the lamp, the driver turns in standby mode, and the whole starter is fully
stopped until the next mains removal and power supply reset.
5. If the lamp is ignited:
If the lamp is ignited, the driver stays in standby mode while monitoring the state of the lamp (loop 2).
During normal operation of the tube, this short pulse is masked by the lamp conduction. If the mains
interruption is really long enough to turn off completely the lamp, a new ignition sequence starts again (loop
3) with 8 other new possible attempts.
9/14
EFS
6/ PREHEAT PHASE DURATION 50-60Hz:
The driver determines the preheat duration by counting mains cycles. This numeric solution brings
naturally a good precision depending only on the mains frequency tolerance.
With the 2 driver versions, the EFS startlight-kit provides a choice of 4 preheat duration’s. The following
table gives the preheat duration before the first ignition attempt. The seven next preheat duration’s, in case
of unsuccessful ignition attempt, last the half of the first one
PREHEAT DURATION
MAINS FREQUENCY
50Hz
DRIVER VERSION
Pin 2 connection
60Hz
EFS2A
EFS2B
EFS2B
GND
VCC
GND
VCC
GND
VCC
1.5s
2.56s
0.74s
1.24s
0.62s
1.03s
7/ TUBE STATE DETECTION:
During the ignition sequence or once the lamp is lit, the starter checks the state of the lamp (lit or off).
To determine this state, the driver reads the lamp voltage through the resistor bridge (R1+R2+R3, R4).
- If the lamp is off, its voltage equal the mains voltage.
- If the lamp is lit, its voltage is only 80 V (for a 58W lamp).
Thus the lamp state is determined by comparison of the lamp voltage with a programmed detection level.
Tolerance effects:
Tolerances on resistors (R1, R2, R3 and R4) as
well as on the integrated comparator bring a
tolerance on the set detection level. Thus the
detection level is included in a range delimited by
the maximum and the minimum detection levels
(DLMAX DLmin).
CORRECT SETTING = NO WAVEFORM
ACROSS THE GREY AREA
OFF Lamp
Voltage
DL
MAX
DL
min
The driver checks the state of the lamp when
mains voltage is maximum, that is to say 5 ms after
the zero crossing mains voltage (50Hz). Here
again internal tolerances bring a tolerance on the
real checking moment (TCmin TCMAX).
LIT Lamp
Voltage
TC min
TC MAX
How to set the detection level?
Only the R4 resistor value can be set to adjust the detection level. Values of resitors R1 to R3 must match
values of the table RECOMMENDED COMPONENTS ACCORDING TO APPLICATION CONDITIONS of
the page 5. Practically the R4 resistor value has to be set so that neither the OFF lamp voltage nor the LIT
lamp voltage cross the grey area.
The DLMAX and DLmin limits can be calculated as follows:
DLMAX =
10/14
x (R4 MAX + R 1min + R 2 min + R 3 min)
1265
.
x (R4 min + R1MAX + R 2 MAX + R 3 MAX )
1122
.
and DLmin =
R4 min
R4 MAX
EFS
8/ E.M.I. CAPACITOR:
As required in the IEC 926 standard (§11.5),
“starters which are interchangeable with glow
starters in accordance with IEC 155 shall contain
means for radio interference suppression, the
effect of which is equivalent to that of the radio
interference suppression capacitor prescribed in
7.12 of IEC 155”.
The EFS starlight-kit is compatible with this 5nF
E.M.I. Capacitor which must be connected directly
across the ASD (between pin 3 “TUBE” and pin
4 “GND”).
On the other hand, this E.M.I. capacitor increases
the striking pulse width of about 55% on positive
temperatures.
ASD
DRIVER
14
1
13
5
12
2
9
7/8/10/11
4
2/3/5/6
4
3
C
E.M.I.
1
Rsense
8.1. Operation in single lamp configuration
The EFS STARLIGHT-KIT is ideal in the following configurations:
- Single Starter / 230V / 50Hz - Single Starter / 230V / 60Hz - Single Starter / 120V / 60Hz

T
U
B
E
AC
MAINS
Note 4: the different driver versions should be chosen according to the table “EFS STARLIGHT KIT PARTS SELECTION” page 2.
Note 5: Components to choose are listed in the table “RECOMMENDED COMPONENTS ACCORDING TO APPLICATION CONDITIONS”
page 5.
8.2. Operation with capacitor for power factor correction:
The EFS STARLIGHT-KIT is also suitable for magnetic ballast including front end parallel capacitor.
The EFS STARLIGHT-KIT is NOT suitable for magnetic ballast including front end serial capacitor.
LEADING MAGNETIC BALLAST WITH
SERIAL CAPACITOR

T
U
B
E
MAGNETIC BALLAST WITH SHUNT
PARALLEL CAPACITOR

T
U
B
E
AC
MAINS
11/14
EFS
8.3. Operation on the 230V/50Hz AC mains in twin tubes configuration
The EFS STARLIGHT-KIT is also suitable for the configurations Twin tubes Starter
Note 5: Components to choose are listed in the table “RECOMMENDED COMPONENTS ACCORDING TO APPLICATION CONDITIONS”
page 5.
The only electrical diagram difference consists of the R4 resistor which needs to be changed from 1 to
2.2kΩ. Without this modification, the starter will generate only one ignition attempt instead of 8 in case of
defective lamp; the loop 3 is removed from the algorithm described in page 9.
AC
MAINS
TWIN TUBE
BALLAST
230V
STARTER
OFF
T
T
U
U
B
B
E
E
230V / 50HZ
ALIGHT
SOCKET
FLUORESCENT
TUBE
OFF
ALIGHT
In the Twin Series 230V/50Hz configuration, the polarity of the two starters must be respected:
In case of no operation of starters, rotate one of the starters of 180° on its socket.
12/14
Rotate of 180°
only one starter
EFS
PACKAGE MECHANICAL DATA
SO14 (Driver)
Dim.
Millimeters
Min. Typ. Max. Min. Typ. Max.
A
a1
G
L
c1
C
a2
b
e
S
e3
a1
E
1.75
b1
0.2
1.6
0.063
b
0.35
0.46 0.014
0.018
b1
0.19
0.25 0.007
0.010
C
0.004
0.5
0.008
0.020
o
c1
D
0.069
0.1
a2
A
Inches
45 (typ.)
M
14
8
F
1
7
D
8.55
8.75 0.336
0.334
E
5.8
6.2
0.244
e
0.228
1.27
e3
0.050
7.62
0.300
F
3.8
4.0
0.150
0.157
G
4.6
5.3
0.181
0.208
L
0.5
1.27 0.020
0.050
0.68
0.027
M
S
o
8 (max.)
13/14
EFS
PACKAGE MECHANICAL DATA
Pentawatt HV with lead forming - TL5 (ASD)
DIMENSIONS
REF.
Millimeters
Min.
Typ.
Inches
Max.
Min.
Typ.
Max.
A
4.3
4.8
0.169
0.188
C
1.22
1.42 0.048
0.056
D
2.4
2.8
0.094
0.110
3.85 0.144
0.152
DIAM 3.65
E
0.35
0.45 0.014
0.018
F
0.65
0.75 0.026
0.030
G1
4.88
5.28 0.192
0.208
G2
7.42
7.82 0.292
0.308
10.4
0.409
10.4 0.396
0.409
H2
H3
10.05
L1
3.3
0.130
L2
14.24
14.64 0.560
0.576
L3
2.34
2.74 0.092
0.108
L5
2.6
L6
15.1
L7
6
R
3
0.102
0.118
15.8 0.594
0.622
6.6
0.260
0.5
0.236
0.020
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of
use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by
implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to
change without notice. This publication supersedes and replaces all information previously supplied.
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