LT1768CGN Linear Technology, LT1768CGN Datasheet - Page 3

• Manufacturer Part Number: LT1768CGN
• Description: IC CTRLR CCFL SGL/MULT HP 16SSOP
• Manufacturer: Linear Technology
• Type: CCFL Controllerr

Specifications of LT1768CGN

• Frequency: 300 ~ 410 kHz
• Current - Supply: 7mA
• Current - Output: 1.5A
• Voltage - Supply: 9 V ~ 24 V
• Operating Temperature: 0°C ~ 125°C
• Package / Case: 16-SSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

ELECTRICAL CHARACTERISTICS
temperature range, otherwise specifications are at T
I
SYMBOL
I
V
V
I
V
I
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: This is the threshold voltage where the lamp current switches
from zero current to minimum lamp current. For V
threshold voltage, lamp current will be at zero. For V
threshold voltage, lamp current will be equal to the minimum lamp
current. Minimum lamp current is set by the value of the resistor from the
R
Note 3: This is the threshold voltage where the device starts to pulse width
modulate the lamp current. For V
lamp current will be equal to the minimum lamp current. For V
greater than the threshold voltage, lamp current will be pulse width
modulated between the minimum lamp current and some higher value.
Minimum lamp current is set by the value of the resistor from the R
to ground. The higher value lamp current is a function of the R
to ground value, and the voltages on the PWM and PROG pins. See
Applications Information for more details.
Note 4: This is the threshold voltage where the lamp current reaches its
maximum value. For V
be no increase in lamp current. For V
lamp current will be at some lower value. Maximum lamp current is set by
PWM
SENSE
GATE
RMIN
DIO1/2
VCCLAMP
SENSE
MIN
pin to ground. See Applications Information for more details.
= –100 A, unless otherwise specified.
PARAMETER
PWM Input Bias Current
PWM Duty Cycle
PWM Frequency
DIO1/2 Positive Voltage
DIO1/2 Negative Voltage
VC High Clamp Voltage
VC Switching Threshold
SENSE Input Bias Current
SENSE Threshold for Current Limit
I
I
GATE Drive Peak Source Current
GATE Drive Peak Sink Current
GATE Drive Saturation Voltage
GATE Drive Clamp Voltage
GATE Drive Low Saturation Voltage
Open LAMP Threshold
FAULT Pin Saturation Voltage
FAULT Pin Leakage Current
Thermal ShutdownTemperature
DIO1/2
DIO1/2
PROG
to I
to I
greater than the threshold voltage, there will
RMAX
RMIN
PROG
Ratio
Ratio
PROG
less than the threshold voltage,
less than the threshold voltage,
PROG
PROG
less than the
greater than the
A
CONDITIONS
V
I
I
V
V
V
V
V
V
V
(Note 5)
V
V
(Note 6)
V
V
I
(Note 9)
I
V
C
DIO
DIO
GATE
FAULT
= 25 C, V
PROG
MAX
PROG
PROG
PROG
SENSE
VC
VC
PROG
PROG
PROG
PROG
VIN
VIN
FAULT
T
= 0.22 F (Note 7)
= V
= V
= 14mA
= –14mA
= 12V, I
= 24V, I
resistor
= 100mA
MIN
The
= 1mA, I
= 4.5V (Note 8)
= 4.5V (Note 8)
= 1.75
= 4.5V (Note 5)
= 4.5V, I
< 0.75V (Note 6)
< 0.75V, I
= 0V
= 5V
VCCLAMP
VCCLAMP
pin
VIN
GATE
GATE
denotes the specifications which apply over the full operating
DI01
DIO1
= 12V, I
, Duty Cycle < 50%, V
, Duty Cycle 80%, V
DIO1
= –100mA, V
= –10mA, V
the value of the resistor from the R
lamp current is a function of the R
voltages on the PWM and PROG pins. See Applications Information for
more details.
Note 5: I
V
DIO1/2 pins from zero until the DC current in the VC voltage source
current equals zero. The I
I
Note 6: I
V
DIO1/2 pins from zero until the DC current in the VC voltage source
current equals zero. The I
I
Note 7: The PWM frequency is set by the equation PWMFREQ = 22Hz/
C
Note 8: For VC voltages less than the switching threshold, GATE switching
is disabled.
Note 9: An open lamp will be detected if either I
the threshold current for at least 1 full PWM cycle.
, I
DIO2
DIO2
or I
PROG
PROG
T
DI02
( F).
or I
DIO2
)/I
)/I
DIO1/2
DIO2
= 0 A, V
to 4.5V, V
to 0.75V, V
RMAX
RMIN
DIO1/2
DIO1/2
= 0, V
= 0, V
PROG
. See Applications Information for more details.
PROG
. See Applications Information for more details.
= 250 A, V
to I
to I
VC
PROG
= 4.5V
VC
VC
PROG
= 4.5V
VC
= 2.5V,
RMAX
RMIN
PROG
= 2.5V,
to 2.5V, and then ramping a DC current out of the
= 4.5V
to 2.5V, and then ramping a DC current out of the
= 1V
ratio is determined by setting I
= 1V
ratio is determined by setting I
PROG
DIO1/2
DIO1/2
= 0V, V
to I
to I
MIN
MAX
RMAX
RMIN
MIN
100
3.6
0.5
9.8
45
90
85
94
45
and R
9
9
pin to ground. The lower value
PWM
ratio is then defined as (I
ratio is then defined as (I
MAX
= 2.5V, I
–1.1
10.2
12.5
DIO1
TYP
110
–25
100
125
160
0.6
1.7
3.7
0.7
1.5
1.5
0.4
0.2
resistors, and the
50
90
98
49
10
10
20
or I
RMIN
RMAX
RMAX
DIO2
LT1768
MAX
–1.3
0.95
130
–30
115
104
150
100
1.9
3.9
0.6
0.3
55
55
11
11
14
to –100 A,
4
to –100 A,
is less than
= –100 A,
DIO1
DIO1
UNITS
+
3
+
A/A
A/A
A/A
A/A
mV
mV
Hz
nA
%
A
V
V
V
V
A
A
A
V
V
V
A
V
C