FAN5640S7X Datasheet, PDF (4/11 Pages) Fairchild Semiconductor – FAN5640 Dual High-Side Constant Current Source for High-Voltage Keypad LED Illumination

Electrical Characteristics
V_IN = 6V to 20V, T_A = -40°C to +85°C, unless otherwise noted. Typical values are at T_A = 25°C, V_IN = 14V, I_LED = 15mA.
Symbol
Parameter
Condition
Min. Typ. Max. Unit
Power Supplies
V_IN
Input Voltage Range
6
20
V
I_Q
Quiescent Current
Measured at GND pin, V_IN = 20V
Measured at GND pin, V_IN = 6V
48
65
µA
44
55
I_SD
Shutdown Supply Current
V_IN = 20V, EN = GND
V_IN = 6V, EN = GND
8
13
µA
5
8
Enable High-Level Input Voltage
V_EN
Enable Low-Level Input Voltage
1.2
V
0.4
I_EN
Enable Input Current
EN = 5V
EN=GND
9
15
µA
0.1 1.0
Regulation
I_LIM1
I_LIM2
∆I_OUT
I_MATCH
V_DO
V_REF
I_MIRROR
∆I_OUT/∆V_IN
T_ON
TSD
Channel 1 Current Limit⁽²⁾
Channel 2 Current Limit⁽²⁾
Output Current Accuracy
2.5mA < I_OUT ≤ 5mA⁽³⁾
5mA < I_OUT ≤ 25mA⁽³⁾
Channel-to-Channel Current Matching⁽⁴⁾
Output Dropout Voltage
Reference Voltage
V_IN – V_OUT at 90% I_OUT
Programmed I_OUT = 25mA
V_IN – V_OUT at 90% I_OUT
Programmed I_OUT = 2.5mA
Current Mirror Ratio
Power Supply Current Dependency
Turn-On Time
Thermal Shutdown Protection
I_OUT / I_RSET
V_OUT = V_IN – 2V⁽⁵⁾
V_IN=14V , I_OUT=12.5mA⁽⁶⁾
Rising Temperature
Hysteresis
30
mA
30
mA
-15
+15
%
-10
+10
-3
+3
%
1.80 2.50
V
0.43 0.60
475
mV
275
0.5 2.0 %/V
5
8
µs
150
°C
20
Notes:
2. If only one channel is needed, IOUT1 can be tied to IOUT2 to boost maximum current to 50mA.
3. R_EXT resistor tolerance adds to the specification limit of the pin RSET to determine overall current accuracy.
4. Matching defined as [(I_OUT1-I_OUT2)/(I_OUT1+I_OUT2)]×100.
5. V_OUT is the total voltage drop across the LED string.
6. Measured from EN crossing 1.8V to output current reaching 90% of target I_OUT.
© 2006 Fairchild Semiconductor Corporation
FAN5640 • Rev. 1.0.2
4
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