A6986H datasheet(27/71 Pages) STMICROELECTRONICS

部品番号	A6986H

部品情報	Automotive 38 V, 2 A synchronous step-down switching regulator with 30 μA

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メーカー	STMICROELECTRONICS [STMicroelectronics]

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The LCM operation satisfies the requirements of the unswitched car body applications (KL30). These applications

are directly connected to the battery and are operating when the engine is disabled. The typical load when the car

is parked is represented by a CAN transceiver and a microcontroller in sleep mode (total load is around 20 - 30

µA). As soon as the transceiver recognizes a valid word in the bus, it awakes the µC and the rest of the

application.

The typical input current request of the module when the car is parked is 100 µA typ. to prevent the battery

discharge over the parking time. In order to minimize the regulator quiescent current request from the input

voltage, the VBIAS pin can be connected to an external voltage source in the range 3 V < VBIAS < 5.5 V (see

Section 5.1 Power supply and voltage reference).

Given the energy stored in the inductor during a burst, the voltage ripple depends on the capacitor value:

VOUT RIPPLE=ΔQILCOUT=∫0TBURST(iL(t)⋅dt)

COUT

(13)

Figure 22. LCM operation over loading condition (part 1)

A6986H

Light-load operation

DS12861 - Rev 3

page 27/71

A6986H データシート(PDF) 27 Page - STMicroelectronics