A80804中文資料Allegro數(shù)據(jù)手冊PDF規(guī)格書

FEATURES AND BENEFITS

? AEC-Q100 qualified

? VIN range: 5.3 to 40 V supply, operates down to 5.1 V

when enabled

? Four independent MOSFET drivers

? Internal and external PWM dimming options

□ Internal PWM dimming set by resistor divider or

analog voltage

□ External PWM dimming set by microcontroller

? Flexible LED analog dimming options

□ Two ADIM pins for LED binning, NTC feedback, or

hybrid analog/PWM dimming

□ Adjustable integrated LED current derating for

elevated VIN

□ Integrated LED current derating for elevated IC

junction temperature

? Combine A80804 devices in parallel for higher number

of LED strings; PWMOUT signal available when used

with internal PWM for master/slave operation

? MINOUT signal available to trim a pre-regulator to

minimize power loss

? Selectable LED current slew rate limit during PWM

dimming

? Extensive fault detection and protection

□ Drain short-to-ground detection

□ Drain short-to-VIN

□ Open LED

□ Thermal protection

□ Programmable input UVLO

DESCRIPTION

The A80804 and A80804-1 are linear, programmable current

controllers capable of accurately regulating current in four

LED strings using external MOSFETs. Each of the four LED

drivers has an independent enable/PWM input and current-sense

resistors and can be independently dimmed with an external

PWM signal, or all channels can be dimmed with internal PWM

dimming and automatic phase shifting. The overall LED current

can be switched between low and full intensity for applications

including stop/tail or DRL/position lighting. Multiple analog

dimming options are available to support applications including

LED binning, NTC foldback, or hybrid dimming. A selectable

LED current slew-rate control is available to tune PWM edge

times and improve EMI performance.

The MINOUT feature allows for trimming an external DC-DC

converter to optimize the voltage across the linear current

regulating MOSFETs to minimize power loss.

The A80804 offers several fault detection and protection options

including MOSFET drain short-to-ground, drain short-to-VIN,

open-LED fault protection, internal overtemperature protection,

and undervoltage lockout. The A80804 can be configured for

either one-out-all-out or one-out-continue operation.

The A80804 has a 500 mV current-sense reference for improved

BCI performance. The A80804-1 has a 200 mV current-sense

reference for lower power dissipation in the sense resistor.

The device is packaged in a 32-pin QFN (ET) with exposed pad

for enhanced thermal dissipation and wettable flank construction

for solderability and visual inspection.

APPLICATIONS

? Automotive medium-power LED

lighting systems

? Fog lights, backup lights, daytime

running lights, position lights,

sequential light