TLE4241GM ,Voltage Regulatorapplications resulting in constantbrightness and extended LED lifetime. It is provided in the very ..
TLE4242G ,Voltage Regulatorapplications resulting in constant brightness and extended LEDlifetime. It is provided in the surfa ..
TLE4250G ,Low-Drop Voltage Trackerapplications. Therefore the device is equipped with additionalprotection functions against overload ..
TLE4251D ,Low Drop Voltage Trackerapplications.Data Sheet Rev. 2.4 1 2001-05-07TLE 4251P-TO252-5-1 P-TO263-5-1GND1 51 5I EN ADJ QAEP0 ..
TLE4251G ,Low Drop Voltage TrackerFeatures Output tracking tolerance ≤ ± 0.2% 400 mA output current capability Enable Function Ve ..
TLE4260 ,5 V Low-Drop Voltage RegulatorFeatures• Low-drop voltage• Very low quiescent current• Low starting current consumption• Integrate ..
TMP86CM74AFG , 8 Bit Microcontroller
TMP86CM74AFG , 8 Bit Microcontroller
TMP86F409NG , Microcomputers / Microcomputer Development Systems
TMP86F808DMG , Microcomputers / Microcomputer Development Systems
TMP86F809NG , Microcomputers / Microcomputer Development Systems
TMP86FH09ANG , Microcomputers / Microcomputer Development Systems
TLE4241GM
Voltage Regulator
LED Driver with Adjustable Current
Target Data
TLE4241 GM
FeaturesAdjustable constant output currentWide input voltage rangeLow drop voltageOpen load detectionOvertemperature protectionShort circuit proofReverse polarity proofWide temperature range : –40�C
Functional Description
The TLE4241GM is an integrated adjustable constant current source. It provides an
output current adjustable via different means (SET, PWM, reference resistor) which is
kept nearly independent from load and supply voltage changes. The IC is designed to
supply LEDs under the severe conditions of automotive applications resulting in constant
brightness and extended LED lifetime. It is provided in the very small P-DSO-8-9 (Micro
8) package. Protection circuits prevent damage to the device in case of overload, short
circuit, reverse polarity and overtemperature. The connected LEDs are protected against
reverse polarity as well as excess voltages up to 45 V. A status output allows handling
of open load and short circuit at the main output. PWM input offers the possibility to adjust the LED brightness by pulse width
modulation.
With an implemented high/low current switch the output current level can be reduced e.g.
for brake/tail light application.
The implemented features such as adjustable output current, the high/low current switch
and the provided PWM input make the device well suited for a broad range of LED and
other applications.
Circuit Description
Figure1Block Diagram
An internal reference voltage of typ. 1.20V supplies the REF pin which is connected to
GND via an external resistor. In the SET=H mode the reference current flowing on the
REF pin is mirrored with an amplification to form the desired output current. The typ.
output current in the SET=H mode calculates
The output current is shown as a function of the reference resistance on page 10 for the
high as well as for the low current mode.
With the PWM input the LED brightness can be regulated via duty cycle. Also PWM=L
sets the TLE 4241 in sleep mode resulting in a very low current consumption of << 1µA
typ. Due to the high impedance of the PWM input (see Fig. IPWM versus VPWM on page
12) the PWM pin can thus also be used as an Enable input.Qtyp�/mA1.20REF/k�----------------------4870.1+�.=
Figure2Pin Configuration (top view)
Pin Definitions and Functions
Application Information
Figure3Application Circuit
Fig. 3 shows a typical application with the TLE 4241GM LED driver. The 3 LEDs are
driven with an adequate supply current adjusted by the resistor RREF. Thus brightness
variations due to forward voltage spread of the LEDs are prevented. The luminosity
spread arising from the LED production process can be compensated via software by an
appropriate duty cycle applied to the PWM pin. Hence selection of the LEDs to forward
voltage as well as to luminosity classes can be spared. The slightly negative temperature
coefficient of the TLE 4241GM output current protects the LEDs against
overtemperature stress if the IC is placed nearby the LEDs. The status output of the LED
driver (ST) detects an open load condition enabling to supervise correct LED function.
The functionality of the ST, SET and PWM as well as their timings are shown in Fig. 4.
Figure4Function and Timing Diagram
Absolute Maximum Ratings
– 40 �C < Tj < 150 �C
Input
Output
Status Output
Reference Input
Pulse Width Modulation Input
High/Low Current Input
Temperatures
Note:Maximum ratings are absolute ratings; exceeding any one of these values may
cause irreversible damage to the integrated circuit
Thermal ResistancesWorst case regarding peak temperature; mounted on PCB 80�80�1.5mm3, 35�m Cu, 300mm2 heat sink
area.
Operating Range
Absolute Maximum Ratings (cont’d)
– 40 �C < Tj < 150 �C
