A6260KLJTR-T Allegro Microsystems Inc, A6260KLJTR-T Datasheet - Page 6

• Manufacturer Part Number: A6260KLJTR-T
• Description: IC LED DRIVER AUTOMOTIVE 8-SOIC
• Manufacturer: Allegro Microsystems Inc
• Type: Automotiver

Specifications of A6260KLJTR-T

• Topology: Linear (LDO), PWM
• Constant Current: Yes
• Number Of Outputs: 1
• Internal Driver: Yes
• Type - Primary: Automotive
• Type - Secondary: High Brightness LED (HBLED)
• Voltage - Supply: 6 V ~ 40 V
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width) Exposed Pad, 8-eSOIC. 8-HSOIC
• Operating Temperature: -40°C ~ 125°C
• Current - Output / Channel: 350mA
• Internal Switch(s): Yes
• Led Driver Application: Automotive
• No. Of Outputs: 1
• Output Current: 367mA
• Output Voltage: 3V
• Input Voltage: 6V To 40V
• Dimming Control Type: PWM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Frequency: -
• Efficiency: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 620-1252-2; A6260KJPTR-T

A6260
dedicated sense resistor, which determines its share of the current
provided to the LED.
LED Brightness
Although the LED brightness can be controlled by changing the
current (intensity) this may slightly affect the color or the color
temperature of the light from the LED. When multiple LEDs
are used, it is usually more desirable to control the brightness by
switching the fixed LED current with a pulse width modulated
signal. This allows the LED brightness to be set using a digital
control input with little effect on the LED color.
In the A6260, the brightness level can be controlled by a PWM
signal applied to the EN input. This controls both the low-side
linear regulator and the high-side switch.
When EN is switched from high to low, the low-side regulator
reduces the current to zero before allowing the high-side switch
to turn off.
When EN is switched from low to high, the high-side switch is
turned on before the low-side regulator increases the current to
the full operating level.
To assist EMC, the rate of change of the LED current is limited
and the current will rise and fall within the limits (t
the Electrical Characteristics table.
Note that EN can be used for PWM dimming even when the
high-side switch is bypassed. (See figure 4(d)).
Sleep Mode
When EN is held low, the A6260 will be in shutdown mode and
all internal circuits will be in a low-power sleep mode. In this
mode, the input current, I
Figure 1. Short circuit conditions detected
(a) LA Short to Supply
Permitted because
current remains
regulated
GND
A6260
VIN
LC
LA
INS
, will be less than 10 μA. This means
(b) LA Short to Ground
Detected when switch
current exceeds trip
value for longer than
3 μs, released when
V
LC
GND
A6260
VIN
>V
LC
LA
SCCR
r
, t
High Brightness LED Current Regulator
f
) defined in
(c) LC Short to Supply
Current remains
regulated, thermal
shutdown provides
protection
GND
A6260
VIN
LC
LA
that the complete circuit, including LEDs, may remain connected
to the power supply under all conditions.
Safety Features
The circuit includes several features to ensure safe operation and
to protect the LEDs and the A6260:
▪ The high-side switch between VIN and LA has overcurrent
▪ The current regulator between LC and LSS provides a natural
▪ The thermal monitor reduces the regulated current as the
▪ Thermal shutdown completely disables the outputs under
Short Circuit Detection
A total of five short circuit conditions can exist as illustrated in
figure 1.
LA Short to Supply
because the current remains regulated by the current sink. This
configuration may also be used in applications with low supply
voltages (see figure 4d in the Applications Information section).
LA Short to Ground
the high-side switch current exceeds the trip value, I
longer than the overcurrent detection time, t
When a short is detected, the switch and the regulator are both
disabled. When the voltage at LC drops below the short release
voltage, V
then sourced from LA to provide a short circuit monitor. When
detection and a current limiter. It assumes that a short circuit is
present if the current exceeds the trip value, I
than the overcurrent detection time, t
current limit due to the regulation.
temperature rises.
extreme overtemperature conditions.
SCCR
(d) LC Short to Ground
Detected when switch
current exceeds trip
value for longer than
3 μs, released when
V
, a low value current, I
LC
GND
A6260
VIN
>V
(figure 1a) This condition is permitted
LA
LC
SCCR
(figure 1b) This condition is detected when
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
SCU
OCD
(1.1 mA typical), is
(e) LA Short to LC
.
Current remains
regulated, thermal
shutdown provides
protection
OCD
GND
A6260
VIN
LAOC
(3 μs typical).
LA
LC
, for longer
LAOC
, for
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