Max8759 low-cost, smbus, ccfl backlight controller, Electrical characteristics (continued) – Rainbow Electronics MAX8759 User Manual
Page 3
MAX8759
Low-Cost, SMBus, CCFL Backlight Controller
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V
BATT
= 12V, V
CC
= V
DD,
T
A
= 0°C to +85°C. Typical values are at T
A
= +25
°C, unless otherwise noted.)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
0 < V
IFB1,2
< 3V
-3
+3
IFB1, IFB2 Input Bias Current
-3V < V
IFB1,2
< 0
-230
µA
IFB1, IFB2 Lamp-Out Threshold
575
600
625
mV
IFB1, IFB2 to COMP Transconductance
0.5V < V
COMP
< 4V
60
100
160
µS
COMP Output Impedance
6
12
24
M
Ω
COMP Discharge Current During Overvoltage
or Overcurrent Fault
V
VFB
= 2.6V or V
ISEC
= 1.5V
500
1000
2000
µA
COMP Discharge Current During DPWM
Off-Time
V
COMP
= 1.5V
90
110
130
µA
DPWM Rising-to-Falling Ratio
V
IFB1,2
= 0
2.5
ISEC Input Voltage Range
-3
+3
V
ISEC Overcurrent Threshold
1.18
1.21
1.26
V
ISEC Input Bias Current
V
ISEC
= 1.25V
-0.3
+0.3
µA
VFB Input Voltage Range
-4
+4
V
VFB Input Impedance
150
300
450
M
Ω
VFB Overvoltage Threshold
2.1
2.3
2.5
V
VFB Undervoltage Threshold
210
240
280
mV
VFB Undervoltage Delay
R
FREQ
= 169k
Ω
250
µs
R
FREQ
= 169k
Ω, T
A
= +25°C to +85°C
207
210
213
R
FREQ
= 169k
Ω
205
210
215
R
FREQ
= 340k
Ω
106
DPWM Oscillator Frequency
R
FREQ
= 100k
Ω
343
Hz
PWMO Output Impedance
20
40
60
k
Ω
PWMI Input Low Voltage
0.7
V
PWMI Input High Voltage
2.1
V
PWMI Input Hysteresis
300
mV
PWMI Input Bias Current
-0.3
+0.3
µA
PWMI Input Frequency Range
5
50
kHz
PWMI Full-Range Accuracy
5
LSB
PWMI duty cycle = 100%
98
100
PWMI duty cycle = 50%
48
50
52
PWMI Brightness Setting
PWMI duty cycle = 0%
9.7
10.0
10.3
%
ALS Full-Adjustment Range
0
1.8
V
ALS Full-Range Accuracy
5
LSB
ALS Input Bias Current
-0.1
+0.1
µA
VALS Output Voltage
MAX8759 is enabled, 6V < V
BATT
< 28V,
I
LOAD
= 1mA
5.10
5.30
5.50
V
VALS Leakage Current
MAX8759 is disabled, VALS = GND
-3
+3
µA
VALS On-Resistance
MAX8759 is enabled
30
60
Ω