L6520
L6521
Highly integrated ballast controller for TL and CFL
Features
■Half bridge circuit able to drive both BJT and MOSFET transistors
■Very accurate oscillator precision in wide operating temperature range
■BJTs' storage time compensation
■Preheated start and instant start
■Hard switching protection
■Overcurrent / voltage protection
■Choke saturation control
■End-of-life protection
■Programmable without capacitors
SO8
Applications
■Electronic ballasts (TL, Industrial CFL)
■Integrated CFLs
Table 1. |
Device summary |
|
|
Order codes |
Package |
Packaging |
|
|
|
|
|
L6520 |
|
|
Tube |
|
|
|
|
L6520TR |
|
SO8 |
Tape and reel |
|
|
|
|
L6521 |
|
Tube |
|
|
|
||
|
|
|
|
L6521TR |
|
|
Tape and reel |
|
|
|
|
|
|
|
|
|
|
3:0BGHW |
|
|
9&& |
|
|
9FF |
||
|
|
|
|
|
|
|
|
|
9 |
|
9 |
9 |
6WDUW8S |
9 9 |
|
|
|||
|
|
|
|
|
|
|
|
|
,QWHUQDO 95HJ |
|
(2/ |
9 |
|
/2*,& |
9 |
|
|||
|
&25( |
|||
|
|
|
,1 |
|
|
|
|
|
|
|
|
9 |
|
|
|
|
9FF |
|
|
|
|
X$ |
|
|
|
)35( |
|
|
|
|
|
|
|
$'&
|
9FF |
89/2 |
+6' |
/6'
7[+ 7[0 7[/
7KUHVKROG 08;
+%&6
%ORFN&&&
*1'
March 2011 |
Doc ID 16998 Rev 3 |
1/19 |
www.st.com
Contents |
L6520, L6521 |
|
|
Contents
1 |
Description . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
. 3 |
|
2 |
Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
4 |
||
3 |
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
5 |
||
4 |
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
6 |
||
5 |
Functions description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
9 |
||
|
5.1 |
Start-up |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
9 |
|
5.2 |
Preheating and instant start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
9 |
|
|
5.3 |
Ignition |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
10 |
|
5.4 |
Run mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
10 |
|
|
5.5 |
Storage time compensation network . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
10 |
|
|
5.6 |
Current control circuit (CCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
11 |
|
|
|
5.6.1 |
Hard switching protection (HSP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
11 |
|
|
5.6.2 |
Overcurrent protection (OCPH) during ignition mode . . . . . . . . . . . . . . |
11 |
|
|
5.6.3 |
Overcurrent protection (OCPL) during run mode . . . . . . . . . . . . . . . . . . |
11 |
|
|
5.6.4 |
Choke saturation control (CSC) during ignition and run mode . . . . . . . |
12 |
5.7 End of life (EOL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.8 Summary of protections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6 |
Typical electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
14 |
7 |
Application examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
15 |
8 |
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
16 |
9 |
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
18 |
2/19 |
Doc ID 16998 Rev 3 |
L6520, L6521 |
Description |
|
|
The L6520/1 is the first highly integrated ballast controller in the market able to drive both BJTs and MOSFETs, providing all the necessary protections to ensure the maximum reliability of the application in compliance with major safety and power consumption regulations.
By adopting BJTs switches in the application, the IC allows to replace more expensive MOSFETs, strongly reducing the system cost without compromises.
The IC represents also the best and cost effective solution to replace self oscillating solutions when the key requirement is the reliability of the ballast. The benefits are an increased MTBF and a reduction of the costs due to the return from the field.
The higher level of flexibility and integration provided allows the possibility to quickly design ballast with any kind of lamp topology/size/power, without limitations. Depending on the power of the lamp, the IC can work without PFC, with passive PFC or with active PFC. In the latter case the L6562A from STMicroelectronics is the suggested IC for the most cost effective solution.
The IC is fully programmable using only resistors and offers over current protections, choke saturation control and hard switching protection thanks to a sophisticated current control circuit (CCC). In ignition, the CCC limits both the maximum lamp voltage in case of old or broken lamp, and also the lamp current in case of inductor saturation.
When the IC is driving bipolar transistors, a variable dead time ensures the correct base discharge time avoiding cross conduction phenomena. Moreover, the IC prevents the failure due to the lamp's end of life (EOL).
Doc ID 16998 Rev 3 |
3/19 |
Pin connection |
|
|
|
|
L6520, L6521 |
||
|
|
|
|
|
|
|
|
2 |
Pin connection |
|
|
|
|
|
|
|
|
Figure 2. Pin connection |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
)35( |
|
|
|
|
9&& |
|
|
|
|
||||
|
|
(2/ |
|
|
|
|
+6' |
|
|
|
|
||||
|
|
|
|
||||
|
|
+%&6 |
|
|
|
|
/6' |
|
|
|
|
||||
|
|
|
|
||||
|
|
3:0BGHW |
|
|
|
|
|
|
|
|
|
||||
|
|
|
|
*1' |
|||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Table 2. |
Pin description |
|
Symbol |
Pin |
Description |
|
|
|
FPRE |
1 |
Preheating frequency programming and ignition modes selection |
|
|
|
EOL |
2 |
Window comparator input |
|
|
|
HBCS |
3 |
Current sensing input |
|
|
|
PWM_det |
4 |
Half bridge middle point monitor |
|
|
|
GND |
5 |
IC power and signal ground |
|
|
|
LSD |
6 |
Low side driver output |
|
|
|
HSD |
7 |
High side driver output |
|
|
|
VCC |
8 |
Power supply |
|
|
|
4/19 |
Doc ID 16998 Rev 3 |
L6520, L6521 |
|
|
|
|
Maximum ratings |
||||||
|
|
|
|
|
|
|
|
|
|
|
|
3 |
Maximum ratings |
|
|
|
|
|
|
|
|
|
|
Table 3. |
Absolute maximum ratings |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Symbol |
Pin |
Parameter |
|
|
Conditions |
|
|
|
Value |
|
Unit |
|
|
|
|
|
|
|
|
|
|||
VZ |
8 |
Active clamp protection voltage |
Active clamp protection must not be supplied |
|
18.5 |
|
V |
||||
by a low impedance voltage source |
|
|
|
|
|||||||
|
|
|
|
|
|
|
|
|
|
||
IVCC |
8 |
Active clamp protection current |
During low consumption state |
|
|
|
2 |
|
mA |
||
VOD1 |
6,7 |
Differential voltage between |
|
|
(1) |
|
|
|
18.5 |
|
V |
driver output and VCC |
VOD1 = VCC – VOUT |
|
|
|
|
||||||
|
|
|
|
|
|
|
|
|
|
|
|
V |
6,7 |
Differential voltage between |
V |
= V |
GND (1) |
|
|
|
18.5 |
|
V |
driver output and GND |
|
|
|
|
|||||||
OD2 |
|
OD2 |
OUT – |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
VFPRE |
1 |
FPRE positive voltage |
|
|
|
|
|
|
5 |
|
V |
VFPRE |
1 |
FPRE negative voltage |
|
|
|
|
|
|
-0.3 |
|
V |
VPWM_det |
4 |
PWM_det pin positive voltage |
PWM_det input current < 5mA |
|
|
|
5.1 |
|
V |
||
VPWM_det |
4 |
PWM_det pin negative voltage |
PWM_det output current < 0.1mA |
|
|
|
-0.3 |
|
V |
||
VHBCS |
3 |
HBCS positive voltage |
|
|
|
|
|
|
5 |
|
V |
VHBCS |
3 |
HBCS negative voltage |
HBCS output current < 2mA |
|
|
|
-5 |
|
V |
||
VEOL,max |
2 |
EOL positive voltage |
EOL input current < 5mA |
|
|
|
5 |
|
V |
||
VEOL,min |
2 |
EOL negative voltage |
EOL output current < 0.1mA |
|
|
|
-0.3 |
|
V |
||
1. VOUT refers to the voltage at either LVG pin or HVG pin |
|
|
|
|
|
|
|
|
|
||
Table 4. |
Thermal data |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
||
Symbol |
|
Description |
|
|
|
|
Value |
|
Unit |
||
|
|
|
|
|
|
|
|
|
|||
RthJA |
Max. thermal resistance junction to ambient |
|
|
|
|
150 |
|
°C/W |
|||
|
|
|
|
|
|
|
|
|
|||
TJ |
Junction operating temperature range |
|
|
|
|
-40 to 150 |
|
°C |
|||
|
|
|
|
|
|
|
|
|
|
||
TSTG |
Storage temperature |
|
|
|
|
|
-55 to 150 |
|
°C |
||
|
|
|
|
|
|
|
|
|
|
|
|
Doc ID 16998 Rev 3 |
5/19 |
Electrical characteristics |
L6520, L6521 |
|
|
|
|
|
|
VCC = 16 V, TA = -25 °C to 85 °C, unless otherwise specified |
|
|
|
|
||||
Table 5. |
Electrical characteristics |
|
|
|
|
|
|
|
||||
|
|
|
|
|
|
|
|
|
||||
Symbol |
Pin |
Parameter |
|
Test condition |
Min. |
Typ. |
Max. |
Unit |
||||
|
|
|
|
|
|
|
|
|
|
|||
Supply voltage |
|
|
|
|
|
|
|
|
||||
|
|
|
|
|
|
|
|
|
|
|||
|
V |
CC |
VCC |
Operating range |
After turn-on (1) |
10.5 |
|
V |
V |
|||
|
|
|
|
|
|
|
|
|
|
Z |
|
|
VCC(ON) |
VCC |
Turn-on threshold |
|
|
|
13.5 |
15 |
16.5 |
V |
|||
VCC(OFF) |
VCC |
Turn-off threshold |
|
|
|
10.5 |
11.5 |
12.5 |
V |
|||
|
|
VZ |
VCC |
Zener voltage |
IZ = 2 mA |
16.5 |
17.5 |
18.5 |
V |
|||
Supply current |
|
|
|
|
|
|
|
|
||||
|
|
|
|
|
|
|
|
|||||
IST-UP |
VCC |
Start-up current |
Before turn-on, (VCC = 13 V) |
|
130 |
200 |
µA |
|||||
|
|
ICC |
VCC |
Operating supply current |
No load |
|
|
8 |
10 |
mA |
||
|
|
IQ |
VCC |
Quiescent current |
IDLE mode, (2) |
|
150 |
220 |
µA |
|||
Timing and oscillator |
|
|
|
|
|
|
|
|||||
|
|
|
|
|
|
|
|
|
|
|||
|
|
D |
|
Output duty cycle |
Run mode |
49.5 |
50 |
50.5 |
% |
|||
|
|
|
|
|
|
|
|
|
|
|
|
|
tDEAD |
|
Fixed dead time |
(3) |
|
|
1.24 |
1.42 |
1.6 |
µs |
|||
|
|
|
|
|||||||||
|
fRUN |
|
HB run frequency |
TAMB = 25° C |
46 |
46.6 |
47.2 |
kHz |
||||
|
|
|
|
|
43.2 |
|
47.8 |
kHz |
||||
|
|
|
|
|
|
|
|
|
|
|||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
fPRE |
|
Max programmable |
RFPRE = 24.9 kΩ |
96 |
100 |
104 |
kHz |
||||
|
|
preheating frequency |
||||||||||
|
|
|
|
|
|
R |
≥ 196 Ω, (1), (4), L6520 |
|
1.5 |
|
s |
|
|
tPRE |
|
Preheating time |
FPRE |
|
|
|
|
|
|
||
|
|
R |
≥ 196 Ω, (2), (4), L6521 |
|
0.8 |
|
|
|||||
|
|
|
|
|
|
FPRE |
|
|
|
|
|
|
|
|
f |
|
|
HB instant start initial |
FPRE connected to GND, (2) |
|
85 |
|
kHz |
||
|
|
|
|
frequency |
|
|
||||||
|
|
INS |
|
|
|
|
|
|
|
|
||
|
|
|
|
|
|
|
|
|
|
|
|
|
df |
|
/dt |
|
Ignition time frequency sweep |
(4), T |
|
= 25 °C |
|
-2.75 |
|
kHz/ms |
|
|
|
IGN |
|
rate |
AMB |
|
|
|
|
|
||
|
|
|
|
|
|
|
|
|
|
|
|
|
df |
|
|
/dt |
|
Frequency sweep rate after |
(4), T |
|
= 25 °C |
|
-500 |
|
Hz/ms |
|
CCC |
|
overcurrent |
AMB |
|
|
|
|
|
|||
|
|
|
|
|
|
|
|
|
|
|
||
IFPRE |
FPRE |
FPRE current reference |
TAMB = 25 °C |
200 |
202 |
204 |
µA |
|||||
|
|
|
192 |
|
204 |
|||||||
|
|
|
|
|
|
|
|
|
|
|
||
|
|
|
|
|
|
|
|
|||||
tON,min |
HSD LSD |
Minimum half bridge on time |
TAMB = 25 °C |
|
1 |
|
µs |
|||||
Half bridge drivers |
|
|
|
|
|
|
|
|
||||
|
|
|
|
|
|
|
|
|
|
|||
|
|
VOL |
HSD LSD |
Output low voltage |
Iload = 300 mA |
|
|
3 |
V |
a. This is a preliminary version: all the parameters are subject to change
6/19 |
Doc ID 16998 Rev 3 |