A6214 Datasheet, PDF (1/25 Pages) Allegro MicroSystems – 2 A maximum output over operating temperature range

A6214 and A6216
Automotive-Grade, Constant-Current 2 A
PWM Dimmable Buck Regulator LED Driver
FEATURES AND BENEFITS
• AEC-Q100 qualified
• Supply voltage 4.5 to 55 V
• 2 A maximum output over operating temperature range
• Integrated MOSFET switch
• Able to use either Schottky or silicon low-side diode
• True average output current control
• Internal control loop compensation
• Integrated 5 V, 10 mA regulator for driving external load
• PWM dimming via direct logic input down to 0.1% at 200 Hz
• Standalone internal PWM dimming (A6216)
• Analog dimming for brightness calibration and thermal
foldback
• Low-power shutdown (1 µA typical)
• Fault flag output (A6216)
• LED string open and short protection
• Cycle-by-cycle current limit
• Undervoltage lockout (UVLO) and thermal shutdown (TSD)
• Robust protection against:
□□Adjacent pin-to-pin short
□□Pin-to-GND short
□□Component open/short faults
PACKAGES:
A6214: 10-Pin SOICN (suffix LK)
Not to scale
A6216: 16-Pin eTSSOP (suffix LP)
DESCRIPTION
The A6214 is a single-IC switching regulator that provides
constant-current output to drive high-power LEDs. It integrates
a high-side N-channel DMOS switch for DC-to-DC step- down
(buck) conversion. A true average current is output using a
cycle-by-cycle, controlled on-time method.
Output current is user-selectable by an external current sense
resistor. Output voltage is automatically adjusted to drive
various numbers of LEDs in a single string. This ensures the
optimal system efficiency.
LED dimming is accomplished by a direct logic input
pulse-width-modulation (PWM) signal at the Enable pin.
Alternatively, anAnalog Dimming input can be used to calibrate
the LED current, or implement thermal foldback in conjunction
with external NTC thermistor.
The A6216 has the added capability to generate its own PWM
dimming frequency and duty cycle in stand-alone mode.
The A6214 is provided in a compact 10-pin narrow SOIC
package (suffix LK). The A6216 is in 16-pin TSSOP (suffix
LP), both with exposed pad for enhanced thermal dissipation.
It is lead (Pb) free, with 100% matte-tin leadframe plating.
APPLICATIONS:
Automotive lighting
• Daytime running lights
• Front and rear fog lights
• Turn/stop lights
• Map light
• Dimmable interior lights
Not to scale
V_IN (4.5 to 55 V)
C_IN
GND
External PWM
dimming signal
EN/PWM
External analog
dimming signal
ADIM
R_ON
1
VIN
A6214
SW ¹⁰
C_BOOT
2
TON
BOOT ⁹
D1
3 _EN
CSH ⁸
4 _ADIM
CSL ⁷
5 _VCC
C2
GND ⁶
L1
RSENSE
LED+
C_LED
GND
A6214-16-DS, Rev. 4
Figure 1: A6214 (LK Package) Typical Application Circuit
January 21, 2013
November 1, 2016