L4952
VOLTAGE REGULATOR FOR CAR RADIO APPLICATIONS
OPERATION SUPPLY VOLTAGE 9.5 TO 28V
PEAK SUPPLY OVERVOLTAGE PULSE UP
TO 52V (VS. GND)
FIXED OUTPUT VOLTAGE OF 8.6
0.2V
AND OUTPUT CURRENT UP TO 150mA
VERY LOW DROP OUTPUT STAGE WITH
LOW OUTPUT VOLTAGE DIAGNOSTIC
OUTPUT SHORT CIRCUIT AND THERMAL
OVERLOAD PROTECTION
VERY LOW STANDBY CURRENT (DEVICE
DISABLED)
TWO
INTERNAL
OUTPUT
VOLTAGE
SWITCHES WITH LOW DROPOUT FOR
AM/FM SWITCHING
DRIVER CIRCUIT FOR EXTERNAL HIGH
SIDE SWITCH WITH DROP MONITORING
ENABLE INPUT TO SWITCH ON THE DE-
VICE
ADDITIONAL 10V VERY LOW DROP REGU-
LATOR TO SUPPLY THE VARICAP
DESCRIPTION
The L4952 is a monolithic voltage regulator in an
advanced BCD60II process with high efficient p-
channel transistor. This device is optimized for
Car Radio applications to obtain optimum per-
formance and supply system integration with high
flexibility and minimum peripheral components.
June 2000
BLOCK DIAGRAM
SO20 (12+4+4)
ORDERING NUMBER: L4952D
1/8
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
s
DC supply voltage
-2.2 .. +28
V
V
st
Transient operating supply voltage for t = 400ms
-2.2 .. +52
V
V
o1,2,3,4
Output voltages
-0.3 .. +12
V
V
EN
Input voltage of EN
-0.3 .. +18
V
V
IND
Input voltage for EN2, EN3, HSON
-18 .. +18
V
V
s
-V
IND
Max Voltage Difference between V
s
and logic inputs EN2,
EN3, HSON
52
V
V
DIAG
Diagnostic output
-0.3 .. +20
V
I
o1
Output current out1, out4
short circuit protected
mA
I
o2,3
Output current out2,3 (Note 1)
internally limited
mA
I
oDIAG
Output current Diagnostic
10
mA
I
HSSD
Driver current for external pnp High side switch
internally limited
mA
T
J
Operating junction temperature
-40 .. +150
C
P
o
Power dissipation with on board heat sink 2cm
2
1
W
V
ESD
ESD voltage capability ( MIL 883 C )
2000
V
Note: Current limiter of OUT1 will also protect OUT2 and OUT3 as long as OUT1 is notreverse supplied. O utput capacitors up to 100
F between
OUT and GND will not harm this protection.
THERMAL DATA
Symbol
Parameter
Value
Unit
R
th j-amb
Thermal Resistance Junction to Ambient with on board heatsink
2cm
2
60
C/W
T
JSD
Thermal shutdown junction temperature
>150
C
OUT1
OUT3
EN3
GND
GND
GND
GND
EN2
OUT2
OUT4
DIAG
GND
GND
GND
GND
HSSD
HSSS
HSON
1
3
2
4
5
6
7
8
9
18
17
16
15
14
12
13
11
19
10
20
V
S
EN
D95AU401A
PIN CONNECTION
L4952
2/8
FUNCTIONAL DESCRIPTION
The L4952 is a monolithic voltage regulator with
an output voltage of typically 8.6V and a maxi-
mum output current of 150mA. It 's a device for
audio applications in carradios.
The device contain a precision Bandgap refer-
ence, a output amplifier with overcurrent protec-
tion, two voltage switches, a driver for an external
pnp switch, a discharge circuitry for theft detec-
tion and a overtemperature protection.
For automatic PCB assembly
the package is
SO12+4+4. To use the maximal current of 150mA
a small copper area of 2cm
2
as heat sink on
board (Rth=60K/W) is necessary.
The device has a very low quiescent current in
standby mode. If the digital Input EN is Low the
device is switched off (stand by mode) and if EN
ELECTRICAL CHARACTERISTICS (V
s
= 14V; T
J
= 25
C unless otherwise specified)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
I
s
V
s
Quiescent current
no Load
1.6
5
mA
I
ssb
V
s
standby current
EN = 0V
0
20
A
V
INLEN
Low Voltage EN
-0.3
0.5
V
V
INHEN
High Voltage EN
V
S
= 18V
3.5
18
V
V
IN L EN2,3
EN2, EN3, Low Voltage
-18
1.05
V
V
IN H EN2,3
EN2, EN3, High Voltage
V
S
= 18V
1.45
18
V
V
IN L HSON
HSON Low Voltage
-18
1.0
V
V
IN H HSON
HSON High Voltage
V
S
= 18V
2.0
18
V
I
INH
Current EN2, EN3, HSON
V
In
= 5V
30
70
A
I
INL
Current EN2, EN3, HSON
V
In
= 0V
-10
10
A
I
IN ON/OFF
Current High EN
V
In
= 5V
-10
100
200
A
Voltage Regulator (OUT 1)
V
o1
Output voltage
no load
8.4
8.6
8.8
V
V
DP1
Dropout voltage
V
s
= 8.4V, V
DP1
= V
s
- V
out1
I
o1
= 0.15A, I
02,3
= 0mA
0.16
0.6
V
I
o1
= 0.1A, I
02,3
= 0mA
0.11
0.4
V
I
o1
= 0.05A, I
02,3
= 0mA
0.06
0.2
V
SVRR
Supply Voltage ripple rejection
f = 100Hz, C = 10
F ESR = 5
60
70
dB
V
oLo
Load regulation
10mA < I
o
< 150 mA
30
60
mV
I
oLim1
Current limits
V
OUT
= 8V
150
300
800
mA
Voltage Regulator (OUT 4)
V
o4
Output voltage
no load
9.5
10.0
10.5
V
V
DP4
Dropout voltage
I = 3mA V
s
= 8.6V
0.14
0.3
V
I = 1.5mA V
s
= 8.6V
0.075
0.15
V
SVRR
Supply Voltage ripple rejection
f = 100Hz C = 10
F ESR = 5
30
60
dB
V
o4Lo
Load regulation
0.5mA < I < 3 mA
100
mV
I
o4Lim
Current limits
V
OUT
= 8V
8
60
mA
Diagnostic Output
V
LDIAG
Output Diagnostic Low voltage
R
DIAG
to 5 V = 10K
0.4
V
V
out
Output voltage drop before
diagnostic activation
V
S
> 6V I
O1
= 100mA
I
O2
= I
O3
= 0mA
30
200
mV
Voltage Switches Vout2/3
V
DP2
Dropout V
out2
I
o2
= 50mA, En
2
= H
0.25
0.5
V
I
o2
= 25mA, En
2
= H
0.125
0.25
V
V
DP3
Dropout V
out3
I
o3
= 75mA, En
3
= L
0.25
0.5
V
I
o3
= 40mA, En
3
= L
0.14
0.28
V
High Side Switch Driver
V
DPHS
Low Drop Voltage
I
out
= 50mA, HSON = H
0.26
0.8
V
V
DPHS
Drop detection threshold
V
Dth
= V
S
- V
14
, HSON = H
0.7
1
1.3
V
L4952
3/8
Figure 1: Application Circuit Diagram
Figure 2.
Figure 3.
L4952
4/8
is High the device is switched on. The diagnostic
circuitry detect the low drop voltage.
In this case the DIAG output is going low and can
mute the power output stage to avoid noise on
the loudspeaker.The two internal switches can
switch the stabilized output voltage with P-MOS
Transistors to one of the outputs 2 and 3 with low
drop. This is useful to switch the AM and FM cir-
cuitry on or off.
To control it there are two digital inputs En
2
and En
3
one for each switch. EN
2
is High active and EN
3
is
Low active. It's possible to drive the AM/FM switch
with one digital line (EN
2
and EN
3
together).
The driver for the external High side switch can
switch on and off the external pnp transistor. The
drop detection circuitry avoid the damage of the
external power pnp transistor.
To supply the varicaps and the PLL-opamp of the
car radio a second very low drop 10 V regulator is
available. This regulator in dropout has a typical
resistance of 50
.
Function of the external High side switch
driver
Fig 2 shows the principle circuitry of the external
High side switch. Fig. 3 shows the switch on/off
phase of the external High side switch. At the
time t0 the microcontroller switches on (curve 1 =
output signal of the microcontroller).
The signal on the HSON pin of the L4952 is shown
on curve 2. At t1 the external Power pnp is
switched on. At t2 (V
HSON
= V
SON2
) the internal
comparator compares the drop of the external pnp.
In case of normal operation the drop is smaller than
V
Dth
and no failure will be detected (curve 3).
In case of failure (that mean a higher drop than
V
Dth
) the external power pnp will be switched off
(curve 4). If an error is detected it will be stored in
the internal error flip-flop. The external pnp can
only be switched on again after having turned
HSON off (V
HSON
< V
SON1
) again.
Figure 4: Logic input currents versus input
voltage
Figure 3: Stand by consumption versus
temperature
Supply voltage rejection (C = 10
F, ESR = 4.7
,
Load at OUT4 = 10k
)
Figure 5: Supply rejection versus Frequency.
OUT2 propagation delay (Load = 100
)
Figure 6: OUT2 propagation delay (Load = 100
)
Typical Characteristics (Note 4)
L4952
5/8
Note 4
Typical charcteristics shown by the Figures 3 to
12 are typical parameters. Depending on produc-
tion spread certain deviations may occure. For
limits see pages 2 to 4.
Figure 10: OUT1 voltage versus temperature
Figure 9: (C = 10
F, ESR = 4.7
Load current
0mA and 117mA)
Figure 11: OUT4 supply transient response
(C = 10
F, ESR = 4.7
, Load = 3mA)
Figure 12: OUT4 voltage versus temperature
Figure 7: OUT3 propagation delay (Load = 100
)
Figure 8: OUT1 supply transient rejection
(C = 10
F, ESR = 4.7
, Load at OUT1
= 100
, Load = 10k
)
L4952
6/8
1
1
0
11
20
A
e
B
D
E
L
K
H
A1
C
SO20MEC
h x 45
SO20
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
2.35
2.65
0.093
0.104
A1
0.1
0.3
0.004
0.012
B
0.33
0.51
0.013
0.020
C
0.23
0.32
0.009
0.013
D
12.6
13
0.496
0.512
E
7.4
7.6
0.291
0.299
e
1.27
0.050
H
10
10.65
0.394
0.419
h
0.25
0.75
0.010
0.030
L
0.4
1.27
0.016
0.050
K
0
(min.)8
(max.)
OUTLINE AND
MECHANICAL DATA
L4952
7/8
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of use of such information nor for any infringement of patents or other rights of third parti es 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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L4952
8/8
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