Datasheet L4948 Datasheet (SGS Thomson Microelectronics)



L4948

QUAD VOLTAGE REGULATOR WITH INHIBIT AND RESET

4 OUTPUTS: 10V (300mA); 8V (400mA); 5V
(600mA);5V (100mA)

ALL FOUR OUTPUTS 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 L4948 is a quad output low drop voltage
regulator. All four outputs are low drop: 10V at
300mA (V

) and a 5V st-by line at 100mA (VO4).

(V

O3

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

O1,2,3

The STCAP pin allows the battery voltage to de-

BLOCK DIAGRAM

), 8V at 400mA (VO2), 5V at 600mA

O1

are offduring st-by mode.

MULTIPOWER BCD TECHNOLOGY

Multiwatt 11

ORDERING NUMBER: L4948

cay slowly giving theµP time to store data. This
IC is designed for supplying microcomputer con­trolled systems specially in automotive applica­tions.

June 2000

1/9

L4948

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 -15 to 27 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 12 V
Output Voltage (LVW, Reset) 0 to 12 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

THERMAL DATA

Symbol Parameter Value Unit

Thermal Resistance Junction-case max 2 °C/W

2/9

R

th j-case

L4948

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

S-VO1

V

V

V

O1

V

O1

I

Q

Ι

L

O1

O1

O1

Output Voltage IO1= 300mA; T

Load Regulation IO1= 6 to 300mA 150 mV
Quiescent Current (∆IS)V

Dropout Voltage IO1 = 300mA

Current Limit (Foldback) note1 VO1= 0V 360 800 mA
Max Bat.Trans. RO = 100Ω

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

Rev. Voltage . VS= -15V; RO = 100Ω -0.4 1 V
Ripple rejection f

∆V

O1

Line Regulation
∆V

Output Noise Check Output for AC noise

V

∆V

V

S-VO2

V

O2

O2

∆I

Q

Ι

L

O2

Output Voltage IO2= 400mA; T

Load Regulation IO2 = 8 to 400mA 150 mV
Quiescent Current (∆IS)VS= 14V; IO2= 8mA;

Dropout Voltage IO2= 400mA

Current Limit (Foldback) note1 VO2= 0V 480 960 mA
Max Bat.Trans. RO= 100Ω

= -40to 85°C, unlessotherwisespecified.)

amb

11V < V

S

V

S

RampV
Hold V

RampV
T

amb

< 16V all temps

S

= 14V; IO1= 6mA;

=14V ; IO1= 300mA;

from14 to60V in3-5ms 11 V

S

at 60V for 10ms

S

from60 to14V in3-5ms;

S

=25°C;

all temps

amb

=25°C;

T

=25°C;

amb

all temps

9.7

9.5

9.7

9.5

10
10

10
10

10.3

10.5

10
30

400
600

2

10.3

10.5

Ω

CheckV

I

O1,Tamb

=1KHz;1VppAC;VS=14V

O

= 180mA; IO2= 200mA

O1

=25°C;

all temps

;

9.7

9.5

50

10
10

10.3

10.5

IO3= 400mA; IO4= 40mA;
f

O=10KHz;1VppAC;V

I

= 180mA; IO2= 200mA

O1

=14V

S

;

50 dB

IO3= 400mA; IO4= 40mA;

across VSrange VS= 11V to 26V 50 mV

O1

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

200
using an A weighted filter (20­20KHz)

=25°C;

amb

all temps

7.75

7.60

8

8.25

8

8.40

10

V

= 14V; IO2= 400mA;

S

set V
set V

RampV
Hold V

RampV
T

amb

+1V; T

S=VO2

+1.5V;all temps

S=VO2

from14 to60V in3-5ms 9 V

S

at 60V for 10ms

S

from60 to14V in3-5ms;

S

=25°C;

all temps

amb

=25°C;

7.75

7.60

8
8

35

400

600

2

8.25

8.40

V
V

mA
mA

mV
mV

V
V

V

V
V

dB

µ
µV

V
V

mA
mA

mV
mV

V
V

V

V

3/9

L4948

ELECTRICALCHARACTERISTICS

(continued)

Symbol Parameter Test Condition Min. Typ. Max. Unit

V

O2

V

O2

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

CheckV
all temps

, standard T

O2

amb

=25°C;

7.75

7.60

8

8.25

8

8.40
Rev. Voltage . VS= -15V; t = 30s; RO = 100Ω -0.4 1 V
Ripple rejection f

=1KHz;1VppAC;VS=14V

O

I

= 180mA; IO2= 200mA

O1

50 dB

;

IO3 = 400mA;IO4 = 40mA;

O=10KHz;1VppAC;V

f
I

= 180mA; IO2= 200mA

O1

=14V

S

;

50 dB

IO3= 400mA; IO4= 40mA;

∆V

V

∆V
∆V

V

S-VO3

V

V

V

O2

O3

O3
O3

∆I

Q

I

L

O3

O3

O3

Line Regulation
∆V

across VSrange VS= 10.5V to 26V 40 mV

O2

Output Voltage IO3= 600mA; T

=25°C;

amb

all temps

4.85

4.75

5

5.15

5

5.25
Line Regulation VS= 7V to 26V 40 mV
Load Regulation IO3 = 4 to 600mA 100 mV
Quiescent Current (∆IS)VS= 14V; IO3= 4mA;

V

= 14V; IO3= 600mA;

S

8

40

Dropout Voltage IO3= 600mA

set V
set V

S=VO3
S=VO3

+1V; T
+1.5V;all

amb

=25°C;

400

600
Current Limit (Foldback) note 1 VO3= 0V 720 1440 mA
Max Bat.Trans. RO= 100

RampV
Hold V

RampV
T

Ω

from14 to60V in3-5ms 6 V

S

at 60V for 10ms

S

from60 to14V in3-5ms;

S

=25°C;

amb

all temps

4.85

4.75

2

5

5.15

5

5.25

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

CheckV
all temps

, standard T

O3

amb

=25°C;

4.85

4.75

5

5.15

5

5.25
Rev. Voltage . VS= -15V; RO= 100Ω -0.4 1 V
Ripple rejection f

=1KHz;1VppAC;VS=14V

O

I

O1 = 180mA; IO2 = 200mA;

50 dB

IO3= 400mA; IO4= 40mA;
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

S-VO4

O4

V

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= 7V to 26V 40 mV
Load Regulation IO4= 0.4 to 100mA 80 mV
Quiescent Current VS= 14V; IO4= 2mA;

V

= 14V; IO4= 100mA;

S

450

20

Dropout Voltage IO4= 100mA

set V
set V

S=VO4
S=VO4

+0.5V; T

amb

=25°C;

+0.8V;all temps

400
600

Current Limit (Foldback) note 1 VO4 = 0V 150 300 mA

V
V

V
V

mA
mA

mV
mV

V
V

V

V
V

µV
µ

V
V

µA

mA

mV
mV

V

4/9

L4948

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

from60 to14V 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

= 180mA; IO2= 200mA

O1

=14V

S

;

50 dB

V
V

V

V
V

IO3= 400mA; IO4= 40mA;
f

O= 10KHz; 1VppAC;V

I

O1 = 180mA; IO2 = 200mA;

=14V

S

50 dB

IO3= 400mA; IO4= 40mA;

Output Noise Check Output for AC noise

400

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

200

V

µ

using an A weighted filter (20­20KHz)

ON/OFF Input Current V

V

I ON/OFF

V

R

Input Threshold VS= 14VV

Reset Output Voltage Set VSso that VO4< 4.5V;

= 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

O=200KΩto V

IL

IH

;VIH =”1”

04

1 µA

0
2

0.8
12

0 0.75 V

2.75 5 V

A

µ

V
V

LVW and Reset fallTime Set Measured from 90% to 10% 150 µs
LVW and Reset Rise Time Measured from 90% to 100% 300
LVW Output Threshold Ramp V

down until LVW

S

7.0 8.2 V

s

µ

switches from”1” to a ”0”

LVW Output Voltage STCAP <6.5V;R

V

;VIL= ”0”

O4

STCAP >7.5V;R
V

;VIH =”1”

O4

Reset Output Stability V

Sis set suchthat 1 < V04 <

4V; I

OUT4

O=200K

O

= 2mA; V

Ω

=200KΩ to

=0

ON/OFF

to

0 0.75 V

2.75 50 V

50 mV

meas reset variation

I

q

Note 1:

The L4948 has”Foldback” on its outputs duringcurrent limiting.As the outputloading is increasing thecurrentsupplied by theL4948increases
until a threshold is reached. When the current limiting threshold is reached, the L4948 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

S = 14V; I

V

ON/OFF

V

= 14V; I

bat

= 14V; IO1= 300mA;

V

S

I

O2 = 400mA; IO3 = 600mA;

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

110 mA

15 17

18

A

µ

V
V

5/9

L4948

FUNCTIONAL DESCRIPTION

The L4948 includes a monitoring circuit to warn
the microprocessor if a low voltage or no voltage
condition is occurring. Between 6.5V and 7.5V on
the STCAP pin, the LVW output will go low. This
tells the microprocessor to stop executing code
and save vital information. The reset output will
go low when V

drops 0.15V below it’s typical

04

reading. A reset will occur between a minimumof

TIMING DIAGRAM

5.0

4.5 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 out­put doesn’t go above 0.75V until the V

04 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 7V (typical), the
LVW output will also return to high state.

5.0

Graphs of the Output Curves for V

7.8

O1,2,3 and 4

6/9

L4948

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 L4948 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 theinformationin this way.

7/9

L4948

DIM.

Dia1 3.65 3.85 0.144 0.152

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

A 5 0.197
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 0.886
L2 17.4 18.1 0.685 0.713
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

OUTLINEAND

MECHANICALDATA

Multiwatt11 V

8/9

L4948

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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