TLE 4242G Infineon Technologies, TLE 4242G Datasheet - Page 2

• Manufacturer Part Number: TLE 4242G
• Manufacturer: Infineon Technologies

Specifications of TLE 4242G

• Packages: PG-TO263-7
• Topology: Linear
• Vs (min): 4.5 V
• Vs (max): 24.0 V
• Vq (max): 40.0 V
• Iq (max): 500.0 mA

Circuit Description
Figure 1
An external shunt resistor in the ground path of the connected LEDs is used to sense the
LED current. A regulation loop helds the voltage drop at the shunt resistor on a constant
level of typ. 177 mV. Selecting the shunt resistance permits to adjust the appropriate
constant current level. The typ. output current calculates
where
equation applies in a range of 0.39 Ω ≤
The output current is shown as a function of the reference resistance on
the PWM input the LED brightness can be regulated via duty cycle. Also PWM = L sets
the TLE 4242 in sleep mode resulting in a very low current consumption of << 1 μA typ.
Due to the high impedance of the PWM input (see
PWM Voltage” on Page
Data Sheet
I
Q typ
,
PWM
=
V
REF
V
------------
R
I
REF
REF
1
2
is the reference voltage with a typical level of 177 mV (see
Block Diagram
Bias Supply
Reference
Bandgap
11) the PWM pin can thus also be used as an enable input.
R
GND
REF
4
2
≤ 1.8 Ω.
Comparator
Status
Delay
D
6
“PWM Pin Input Current versus
AEB03500.VSD
Rev. 1.1, 2007-03-20
Page
Page
TLE 4242 G
7
5
3
Q
REF
ST
10). The
10. With
(1)