L6520TR STMicroelectronics, L6520TR Datasheet - Page 9

• Manufacturer Part Number: L6520TR
• Description: IC BALLAST CTRL TL/CFL 8-SOIC
• Manufacturer: STMicroelectronics
• Type: Ballast Controllerr

Specifications of L6520TR

• Current - Supply: 8mA
• Current - Output: 300mA
• Voltage - Supply: 10.5 V ~ 18.5 V
• Operating Temperature: -25°C ~ 85°C
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Frequency: -
• Lead Free Status / Rohs Status: Details
• Other names: 497-11128-2

L6520, L6521
5
5.1
5.2
Functions description
Start-up
During the first start-up ramp of the supply voltage (V
are low impedance to ground (Isink 20 mA min). Once the V
voltage V
of FPRE pin to detect the programmed preheating frequency and the selected ignition mode
(instant or preheated start). When all the IC internal functions are ready, the driver-outputs
are released.
If the preheated start is selected, the half-bridge oscillates at the programmed preheating
frequency, otherwise it starts from 85 kHz (typ.).
Preheating and instant start
The preheating time is 1.5 s (typ.) in the L6520 and 0.8 s (typ.) in the L6521. The FPRE pin
embeds a precise current reference: the voltage read by this pin sets the preheating
frequency or enables the instant start. If the FPRE pin is connected to ground, the instant
start is active and the IC runs immediately into ignition sequence from the starting frequency
of 85 kHz. If the pin FPRE is connected to a resistor equal or higher than 196 Ω , the
preheating frequency can be programmed from 55 kHz upwards till 100 kHz (1.5 kHz/step)
accordingly to
to 1%. After the preheating sequence, the IC runs into ignition mode.
Table 6.
Instant start
F
PRE
CC(ON)
56.5
59.5
62.5
65.5
68.5
71.5
74.5
64.
55
58
61
67
70
73
76
(kHz)
Preheating and instant start
Table
the IC starts its operation. During the first 100 µs the IC senses the status
6. For the best precision the resistor tolerance should be less or equal
R
Doc ID 16998 Rev 3
FPRE
1050
1300
1580
1870
2210
2550
2940
3400
3830
4320
4870
196
383
576
806
0
(Ω)
F
CC
PRE
77.5
80.5
83.5
86.5
89.5
92.5
95.5
98.5
) both driver outputs, LSD and HSD,
100
79
82
85
88
91
94
97
(kHz)
CC
voltage reaches the turn-on
Functions description
R
FPRE
10500
11500
12700
14000
15400
16900
18700
20500
22600
24900
5490
6190
6980
7870
8660
9530
(Ω)
9/19