Datasheet L4946 Datasheet (SGS Thomson Microelectronics)



L4946

QUAD VOLTAGE REGULATOR WITH INHIBIT AND RESET

4 OUTPUTS: 10V (125mA); 8V (250mA); 5V
(200mA);5V (100mA)

10V AND 5V (100mA) OUTPUT ARE LOW
DROP

5V (100mA) ST-BY OUTPUT VOLTAGE

EARLY WARNING OUTPUT FOR SUPPLY
UNDERVOLTAGE(LVW)

THERMAL SHUTDOWN AND CURRENT
LIMITATION(FOLDBACK)

REVERSE BATTERY AND LOAD DUMP
PROTECTION

INHIBIT (ON/OFF)AND RESET FUNCTIONS

DESCRIPTION

The L4946 is a quad output low drop voltage
regulator. The four outputs are a low drop 10V at
125mA (V
200mA (V
100mA (V

), a 8V at 250mA (VO2), a 5V at

O1

) and a low drop 5V st-by line at

O3

).

O4

The IC includes a monitoring circuit to warn if a
low voltage or no voltage condition is occurring.
V

are offduring st-by mode.

O1,2,3

BLOCK DIAGRAM

MULTIPOWER BCD TECHNOLOGY

Multiwatt 11

ORDERING NUMBER: L4946

The STCAP pin allows the battery voltage to de­cay slowly giving theµP time to store data. This
IC is designed for supplying microcomputer con­trolled systems specially in automotive applica­tions.

June 2000

L4946

125mA

250mA

200mA

1/9

L4946

OPERATINGCONDITION

Symbol Parameter Value Unit

V

S

I

L

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value Unit

V

S

V

I

V

O

T

stg

T

j

PIN CONNECTION

Supply Voltage -13.5 to26.5 V
Load Current I

O1

I

O2

I

O3

I

O4

300
400
600
100

Supply Voltage -35 to 60 V
Input Voltage (ON/OFF) 0 to 5 V
Output Voltage (LVW, Reset) 0 to 5 V
Storage Temperature Range -65 to 150
Junction Temperature Range max 150
Load Dump (5ms rise, 115ms decay) 60 V

mA
mA
mA
mA

C

°

C

°

APPLICATIONCIRCUIT

uF

0.1

L4946

THERMAL DATA

Symbol Parameter Value Unit

Thermal Resistance Junction-case max 2 °C/W

2/9

R

th j-case

L4946

ELECTRICAL CHARACTERISTICS (VS= 10.5 to 16V; IO1= 6mA, IO2= 8mA, IO3= 4mA; IO4= 0.4mA;

C

=10µF max; T

O

Symbol Parameter Test Condition Min. Typ. Max. Unit

V

∆V

V

S-VO1

V

V

V

O1

O1

I

Q

Ι

L

O1

O1

O1

Output Voltage IO1= 125mA; T

Load Regulation IO1 = 5 to 125mA 150 mV
Quiescent Current (∆IS)VS= 14V; IO1= 5mA;

Dropout Voltage IO1= 125mA

Current Limit (Foldback) note1 VO1 = 0V 150 300 mA
Max Bat.Trans. RO= 100

Rev. Voltage Trans. VS= -35V; t ≤ 1ms; RO= 100Ω

Rev. Voltage . VS= -15V; RO= 100
Ripple rejection

(by design only)

∆V

V

∆V

V

S-VO2

V

V

V

O1

O2

O2

∆I

Q

Ι

L

O2

O2

O2

Line Regulation

V

∆

Output Voltage IO2= 250mA; T

Load Regulation IO2 = 5 to 250mA 150 mV
Quiescent Current (∆IS)VS= 14V; IO2= 5mA;

Dropout Voltage IO2= 250mA

Current Limit (note1) VO2= 0V 300 600 mA
Max Bat.Trans. RO= 100

Rev. Voltage Trans. VS= -35V; t < 1ms; RO= 100Ω

Rev. Voltage . VS= -15V; t = 30s; RO = 100Ω -0.4 1 V

= -40to 85°C, unlessotherwise specified.)

amb

11V < V

< 16V all temps

S

amb

=25°C;

9.7

9.5

10
10

10.3

10.5

10

V

=14V ; IO1= 125mA;

S

T

=25°C

amb

all temps

18

400
600

Ω

RampV
Hold V

RampV

CheckV

f

O

I

O1 = 90mA; IO2 = 125mA;

from14 to60V in3-5ms 11 V

S

at 60V for 10ms

S

from60to14V in3-5ms;

S

,T

O1

=120-10KHz;1VppAC;VS=14V

T

amb

all temps

amb

all temps

Ω

=25°C;

=25°C;

9.7

9.5

9.7

9.5

10
10

10
10

-0.4 1 V
50

2

10.3

10.5

10.3

10.5

IO3= 75mA; IO4= 50mA;
f

= 20-20KHz; 1VppAC; VS=14V

O

I

= 90mA; IO2= 125mA

O1

;

50 dB

IO3 = 75mA; IO4 = 50mA;

across VSrange VS= 11V to 26V 50 mV

O1

=25°C;

amb

all temps

7.75

7.60

8

8.25

8

8.40

10

V

= 14V; IO2= 250mA;

S

T

=25°C

amb

all temps

35

400
600

Ω

RampV
Hold V

RampV
T

amb

all temps

CheckV

from14 to60V in3-5ms 9 V

S

at 60V for 10ms

S

from60to14V in3-5ms;

S

=25°C;

, standard

O2

T

amb

all temps

=25°C

7.85

7.60

7.85

7.80

8

8.15

8

8.20

8

8.15

8

8.20

2

V
V

mA
mA

mV
mV

V
V

V

V
V

dB

V
V

mA
mA

mV
mV

V
V

V

V
V

3/9

L4946

ELECTRICALCHARACTERISTICS

(continued)

Symbol Parameter Test Condition Min. Typ. Max. Unit

Ripple rejection f

=120-10KHz;1VppAC;VS=14V

O

I

O1 = 90mA; IO2 = 125mA;

50 dB

IO3= 75mA; IO4= 50mA;
f

O= 20-20KHz;1VppAC; V

I

= 90mA; IO2= 125mA

O1

S

;

=14V

50 dB

IO3= 75mA; IO4= 50mA;

V

∆

O2

Line Regulation
∆V

across VSrange VS= 10.5V to 26V 40 mV

O2

Output Noise (design only) Check output for AC noise

200
using A weighted filter (20­20KHz)

Check output for AC noise

400 µV
using 100kHz LP (20-100KHz)

V

∆V
∆

V

S-VO3

V

V

V

O3

O3

V

O3

I

∆

Q

Output Voltage IO3=200mA; T
Line Regulation VS= 7V to 26V 40 mV

Load Regulation IO3= 5 to 200mA 100 mV
Quiescent Current (∆IS)V

= 14V; IO3= 5mA;

S

V

= 14V; IO3= 200mA;

S

Dropout Voltage IO3 = 200mA

= 5mA

I

O3

setV

S=VO3

set V

S=VO3

I

L

O3

O3

Current Limit note 1 VO3= 0V 240 480 mA
Max Bat.Trans. RO= 100

RampV
Hold V

RampV

Ω

from14 to60V in3-5ms 6 V

S

at 60V for 10ms

S

from60to14V in3-5ms;

S

Rev. Voltage Trans. VS = -35V; t < 1ms; RO = 100Ω

CheckV

, standard T

O3

all temps

O3

Rev. Voltage . VS= -15V; RO= 100
Ripple rejection f

O=120-10KHz;1VppAC ; V

I

= 90mA; IO2= 125mA

O1

amb

all temps

+0.3V; T

+0.4V;all

=25°C;

T

=25°C;

amb

alltemps

=25°C;

amb

T

amb

all temps

amb

Ω

=25°C;

=25°C;

=14V

S

;

4.85

4.75

5

5.15

5

5.25

10
25

400

600

400

500

2

4.85

4.75

4.85

4.75

5

5.15

5

5.25

5

5.15

5

5.25

-0.4 1 V
50 dB

IO3= 75mA; IO4= 50mA;
f

=10KHz;1VppAC;VS=14V 50 dB

O

Output Noise Check Output for AC noise

400
using a 100KHz LP filter
Check Output for AC noise

200
using an A weighted filter (20­20KHz)

V

∆V
∆V

V

S-VO4

O4

O4
O4

∆I

Q

Ι

L

Output Voltage IO4= 100mA; T

amb

=25°C;

all temps

4.85

4.75

5

5.15

5

5.25
Line Regulation VS = 7Vto 26V 40 mV
Load Regulation IO4= 0.5 to 100mA 80 mV
Quiescent Current VS= 14V; IO4= 2mA;

V

= 14V; IO4= 100mA;

S

500

20

Dropout Voltage IO4= 100mA

T

=25°C

amb

all temps

400
600

Current Limit (note 1) VO4= 0V 120 300 mA

µ

V
V

mA
mA

mV
mV

mV
mV

V
V

V
V

V

µV
µV

V
V

µA

mA

mV
mV

V

4/9

L4946

ELECTRICALCHARACTERISTICS

(continued)

Symbol Parameter Test Condition Min. Typ. Max. Unit

V

O4

V

O4

V

O4

Max Bat.Trans. RO= 100

RampV
Hold V

RampV
T
all temps

0Ω

from14 to60V in3-5ms 6 V

S

at 60V for 10ms

S

from60to14V in3-5ms;

S

=25°C;

amb

4.85

4.75

6

5

5.15

5

5.25
Rev. Voltage Trans. VS = -35V; t < 1ms; RO = 1000Ω

CheckV

, standard T

O4

=25°C;

amb

all temps

4.85

4.75

5

5.15

5

5.25
Rev. Voltage . VS = -15V; RO = 1000Ω -0.4 1 V
Ripple rejection f

O=1KHz;1VppAC;V

I

= 90mA; IO2= 125mA

O1

=14V

S

;

50 dB

V
V

V

V
V

IO3= 75mA; IO4= 50mA;
f

O= 10KHz;1VppAC;V

I

O1 = 90mA; IO2 = 125mA;

S

=14V

50 dB

IO3= 75mA; IO4= 50mA;

Output Noise (design only) Check output for AC noise

200 µV
using A weighted filter (20­20KHz)

Check output for AC noise

400

V

µ

using 100kHz LP (20-100KHz)

ON/OFF Input Current V

V

I ON/OFF

V

R

Input Threshold VS= 14VV

Reset Output Voltage Set VSso that VO4< 4.5V;

Reset and LVW Output Rise

= 14V; VIH= >2V;

S

V

= 14V; VIL= <0.8V; -10

S

VS= 14V V

R

=200KΩto V04;VIL= ”0”

O

so that VO4-0.15V;

V

S

R

=200KΩto V04;VIH=”1”

O

IL

IH

1 µA

0
2

0.8
5

0 0.4 V

2.75 5 V

100 µs

A

µ

V
V

Time
LVW Output Threshold Ramp V

down until LVW

S

7.0 8.2 V

switches from”1” to a ”0”
LVW and LVW Output Fall Time 150 µs
LVW Output Voltage STCAP<7V;R

V

= ”0”

IL

STCAP >8V;R

V

IH = ”1”

Reset Output Stability V

isset suchthat 1 < V04<

S

4V; I

OUT4

=200KΩ to VO4;

O

=200KΩ to VO4;

O

= 2mA; V

ON/OFF

0 0.4 V

2.75 5 V

50 mV

=0

meas reset variation

I

q

Note 1:

The L4946 has”Foldback” on itsoutputs during currentlimiting. As the outputloading is increasing the current suppliedby theL4946increases
until a threshold is reached. When the current limiting threshold is reached, the L4946 output current will start to accrease as the loading is
continuoing to increase. The point where the output current stortto decrease is the maximum output current.

St-By Quiescent Current (∆IS)V

Maximum Quiescent Current
(∆I

)

S

STCAP Output Voltage V

ON/OFF

V

= 14V; I

S

V

ON/OFF

V

= 14V; I

bat
S = 14V; IO1 = 175mA;

V

I

= 275mA;IO3= 200mA;

O2

I

= 100mA; VO=5V

O4

=24V;

S

V

= 60V. 1ms

S

=0V;IO4= 100mA;

= 0mA

O1,2,3

=0V;IO4= 2mA;

= 0mA

O1,2,3

20 mA

500 µA

100 mA

15 17

18

V
V

5/9

L4946

FUNCTIONAL DESCRIPTION

The L4946 includes a monitoring circuit to warn
the microprocessor if a low voltage or no voltage
condition is occurring. Between 7V and 8V on the
STCAP pin, the LVW output will go low. This tells
the microprocessor to stop executing code and
save vital information. The reset outputwill go low
when V

drops 0.15V below it’s typical reading.

04

A reset will occur between a minimum of 4.5 and
a maximum of 5V on V

. The reset output will go

04

TIMING DIAGRAM

7.5

5.0

low when V

drops 0.15 below it’s typical value.

04

A reset will occur between a minimum of 4.5V
and a maximum of 5V on V

. When the V

04

04

drops between 4.5 and 5V the RESET output
goes low. It is very important that the RESET out-

04

put doesn’t go above 0.75V until the V

output
has gone back above 4.75V (typical). The micro­processor looks for a rising edge. So, any spike
will tell the microprocessor to start operating.
Once the STCAP line passes 7.5V (typical), the
LVW output will also return to high state.

7.5

5.0

Graphs of the Output Curves for V

150µs

O1,2,3 and 4

100µs

150µs100µs

6/9

L4946

The STCAP pin acts like a delay circuit. Due to
the large capacitor (470µF), the STCAP pin allows
the battery voltage to decay slowly giving the mi­croprocessortime to store data.Also, during short
low voltage or negative voltage conditions, the
STCAP pin protects the 5V st-by output from
dropping below the RESET and LVW trip points
The four outputs are expected to follow the bat­tery voltage down to 7V. At 7V typical the LVW
tells the microprocessor to stop operation and

Graphs of the Output Curves for V

O1,2,3 and 4 (Cont.)

save operating data Below 7V the outputs are ex­pected to stay alive and ready for a return of bat­tery.

The L4946 has a st-by mode to keep the micro­processor and memories allive during an ignition
off conditions. The ON/OFFinput pin in controlled
by the microprocessor. An high on the ON/OFF
pin places the part in normal mode. A low on the
ON/OFF pin places the part in st-by mode.V
V

02,V03

willbe off duringst-bymode.

01

,

Notes and Information

The following information is for clarification, not for specificationdefinition.
Please use theinformation in this way.

7/9

L4946

DIM.

Dia1 3.65 3.85 0.144 0.152

MIN. TYP. MAX. MIN. TYP. MAX.

A5
B 2.65 0.104
C 1.6 0.063
D 1 0.039
E 0.49 0.55 0.019 0.022

F 0.88 0.95 0.035 0.037

G 1.45 1.7 1.95 0.057 0.067 0.077

G1 16.75 17 17.25 0.659 0.669 0.679

H1 19.6 0.772
H2 20.2 0.795

L 21.9 22.2 22.5 0.862 0.874 0.886
L1 21.7 22.1 22.5 0.854 0.87
L2 17.4 18.1 0.685
L3 17.25 17.5 17.75 0.679 0.689 0.699
L4 10.3 10.7 10.9 0.406 0.421 0.429
L7 2.65 2.9 0.104 0.114

M 4.25 4.55 4.85 0.167 0.179 0.191

M1 4.73 5.08 5.43 0.186 0.200 0.214

S 1.9 2.6 0.075 0.102

S1 1.9 2.6 0.075 0.102

mm inch

0.197

0.886

0.713

OUTLINE AND

MECHANICAL DATA

Multiwatt11 V

8/9

L4946

Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is
granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are
subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products
are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.

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9/9