L5957

Electrical specifications

Doc ID 14442 Rev 2

9/16

Figure 3.

Typical application circuit

Ignition buffer (push-pull with schmitt trigger)

-

1.031.171.28

V

-

1.181.271.33

V

Hysteresis of ignition buffer

-

30

50

100

mV

1000

1500

2000

μA

Low level sink current

10

15

20

mA

Low level

-

0.3

0.5

V

High level

-

4.5

Vreg2

5.5

V

Rising time

C = 15 pF

-

-

10

μs

Fall time

C = 15 pF

-

-

10

μs

Input clamp current

-

-

2

mA

Input voltage

Operative

0

-

50

V

Enable input (regulators 1,3,4 and power switch)

Voltage threshold

-

1.3

-

2.3

V

Input voltage

Operative

0

-

5

V

1.

Drop condition means that the supply voltage drop down to 100 mV from the regulated output and the regulator is sourcing

its maximal load current.

Table 4.

Electrical characteristics (continued)

Symbol

Parameter

Test condition

Min.

Typ.

Max.

Unit

POWER

SWITCH

REG1

REG2

REG3

REG4

VIN1

EN SW

BU

VIN2

ENREG1-4

HOLD

REG 4

REG 3

REG 2

REG 1

SW

Vs

ENREG3

470 µF

100 nF

Cfilt (*)

Cfilt (*)

Cfilt (*)

22 µF

IGNITION

BUFFER

THERMAL

PROTECTION

RESET

BUFFER

DUMP LOAD

PROTECTION

CRES

10 K

1 nF

47 nF

RES

to µProcessor

to µProcessor

IGNITION

BUFFER

THERMAL

PROTECTION

RESET

BUFFER

DUMP LOAD

PROTECTION

AC00427

CRES

10 K

Ω

1 nF

47 nF

RES

to µProcessor

to µProcessor

470 µF

Cfilt (*)

10 K

Ω

(*) Recommended output filtering capacitors for all the regulators: C range = 5 µF to 100 µF, ESR range = 0.5

Ω to 10 Ω (T= -40 ˚C to +85 ˚C)