L9409 Alternator voltage regulator with load response control

The L9409 is a monolithic multifunction alternator voltage regulator intended for use in automotive applications.

The device regulates the output of an automotive generator by controlling the field winding current by means of either an analog fixed frequency PWM signal or digital fixed frequency PWM signal (LRC). The Load Response Control function is activated in order to eliminate IC engine speed fluctuation and vibrations caused by the insertion of sudden electrical loads during alternator low speed operations (f < 310 Hz). Both the analog and digital duty cycle are applied to a high side driver.

The device is able to regulate the voltage either using a feedback signal from B pin or from S pin depending on application needs. S pin is intended to have a clear direct connection with the positive terminal of the car battery. If this connection gets lost the device will regulate voltage using B pin giving a fail safe functionality.

Using L pin is possible to sense key switch and a pre-excitation duty cycle is applied on the field coil in order to start phase voltage sensing. In the case L connection gets lost, device starts to generate using residual magnetism of the generator.

Field, lamp and relay drivers are protected against short circuit

技术特性

IC regulator for 12 V type alternator
Fixed frequency regulation loop
130 mΩ high side field driver
Fail safe device with double sensing of battery voltage (VB and VS)
Load response control (LRC) function activates after an initial time delay
Self start function from phase frequency
“Z” shaped regulation curve compliant with VW specification.
Key recognition from L input
Field driver, lamp driver and relay driver short protection
Complex diagnostics
Thermal shutdown at 175 °C

管脚定义图

L9409 订购信息

订购型号	产品状态	美金价格	数量	封装	包装形式	温度范围	材料声明
L9409BEABR	Active			LQFP 100 14x14x1.4	Tape And Reel		L9409BEABR
L9409CEFBR	Active			LQFP 100 14x14x1.4	Tape And Reel		L9409CEFBR
L9409CEFAR	Active			LQFP 100 14x14x1.4	Tape And Reel		L9409CEFAR
L9409CEFAY	Active			LQFP 100 14x14x1.4	Tray		L9409CEFAY
L9409BEABY	Active			LQFP 100 14x14x1.4	Tray		L9409BEABY
L9409CEFBY	Active			LQFP 100 14x14x1.4	Tray		L9409CEFBY

DATASHEET

描述	版本	大小
L9409 : DS8833: Alternator voltage regulator with load response control	1	191KB