L4805-L4885-L4892
L4808-L4810-L4812
March 1992
VERY LOW DROP VOLTAGE REGULATORS
.
INPUT/OUTPUT DROP TYP. 0.4V
.
400mA OUTPUT CURRENT
.
LOW QUIESCENT CURRENT
.
REVERSE POLARITY PROTECTION
.
OVERVOLTAGE PROTECTION (
60V)
.
FOLDBACK CURRENT LIMITING
.
THERMAL SHUTDOWN
TO-220
DESCRIPTION
L4800 series devices are voltage regulators with a
very low voltage drop (typically 0.4V at full rated cur-
rent), output current up to 400mA, low quiescent
current and comprehensiveon-chip protection.The-
se devices are protected against load dump and
field decay transients of
60V, polarity reversal and
overheating. A foldback current limiter protects
against load short circuits. Available in 5V, 8.5V,
9.2V,10V and 12V versions (all
4%, T
I
= 25
C) the-
se regulators are designed for automotive, industrial
and consumer applications where low consumption
is particularly important.
BLOCK DIAGRAM
In automotive applications the L4805 is ideal for 5V
logic supplies becauseit can operateeven when the
batteryvoltage falls below 6V. In battery backup and
standby applications the low consumption of these
devices extends battery life.
SO T-82
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ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
I
DC Input Voltage
+ 35
V
DC Input Reverse Voltage
- 18
V
Transient Input Overvoltages :
Load Dump :
5ms < T
rise
< 10ms,
f
Fall Time Constant = 100ms,
R
source
< 0.5
Field Decay :
5ms < t
fall
< 10ms, R
source
< 10
r
Rise Time Constant = 33ms
60
- 60
V
V
T
j
, T
stg
Junction and Storage Temperature Range
- 55 to + 150
C
THERMAL DATA
Symbol
Parameter
SOT82
TO220
Unit
R
th j-case
Thermal Resistance Junction-case
Max.
8
4
C/W
R
th j-amb
Thermal Resistance Junction-ambient
Max.
100
75
C/W
PIN CONNECTION (top view)
TEST AND APPLICATION CIRCUIT
The output capacitor is required for stability. Though
the 100
F shown is the minimum recommended
value, actual size and type may vary depending
upon the application load and temperature range.
Capacitor effectiveseries resistance (ESR) also fac-
tors in the IC stability. Since ESR varies from one
brand to the next,some bench work may be required
to determine the minimum capacitor value to use in
production. Worst-case is usually determined at the
minimum ambient temperature and maximum load
expected.
Output capacitors can be increased in size to any
desired value above the minimum. One possible
purpose of this would be to maintain the output vol-
tages during brief conditions of negative input tran-
sients that might be characteristics of a particular
system.
Capacitors must also be rated at all ambient tempe-
rature expected in the system. Many aluminum type
electrolytics will freeze at temperatures less than
30
C, reducing their effective capacitance to zero.
To maintain regulator stability down to 40
C, ca-
pacitors rated at that temperature (such as tan-
talums) must be used.
Order Codes
Output Voltage
TO-220
SOT-82
L4805CV
L4808CV
L4885CV
L4892CV
L4810CV
L4812CV
L4805CX
L4808CX
L4885CX
L4892CX
L4810CX
L4812CX
5V
8V
8.5 V
9.2 V
10 V
12 V
L4805-L4808-L4885-L4892-L4810-L4812
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Notes :
1. This limits are guaranteed by design, correlation and statistical control on production samples over the indicated temperature and
supply voltage ranges..
2. For a DC voltage 26V < Vi < 35V the device is not operating.
ELECTRICAL CHARACTERISTICS (V
I
= 14.4V; C
O
= 100
F; T
j
= 25
C unless otherwise specified.)
Symbol
Parameter
T est Con di tio n
Min.
Typ.
Max.
Uni t
V
O
Output Voltage
I
O
= 5mA to 400mA (L4805)
4.80
5.00
5.20
V
I
O
= 5mA to 400mA (L4808)
7.68
8.00
8.32
V
I
O
= 5mA to 400mA (L4810)
8.16
8.50
8.84
V
I
O
= 5mA to 400mA (L4812)
8.83
9.20
9.57
V
I
O
= 5mA to 400mA (L4885)
9.60
10.00
10.40
V
I
O
= 300mA (L4892)
11.50
12.00
12.50
V
V
I
Operating Input Voltage
26
V
V
O
/V
O
Line Regulation
VI = 13 to 26V; I
O
= 5mA
1
10
mV/V
V
O
/V
O
Load Regulation
IO = 5 to 400mA*
3
15
mV/V
V
I
- V
O
Dropout Voltage
I
O
= 400mA*
0.4
0.7
V
I
O
= 150mA
0.2
0.4
V
I
q
Quiescent Current
I
O
= 0mA
0.8
2
mA
I
O
= 150mA
25
45
mA
I
O
= 400mA*
65
90
mA
V
O
T
V
O
Temperature Output Voltage
Drift
0.1
mV
C
V
SVR
Supply Voltage Rejection
I
O
= 350mA; f = 320Hz;
C
O
= 100
F; V
I
= V
O
+3V+2V
pp
60
dB
I
O
Max Output Current
800
mA
I
SC
Output Short Circuit Current
(fold back condition)
350
500
mA
* only for L4892 the current test conditions is I
O
= 300mA
ELECTRICAL CHARACTERISTICS (V
I
= 14.4V; C
O
= 100
F; T
j
= -40 to 125
C (note 1) unless
otherwise specified.)
Symbol
Parameter
T est Con di tio n
Min.
Typ.
Max.
Uni t
V
O
Output Voltage
I
O
= 5mA to 400mA (L4805)
4.70
5.00
5.30
V
I
O
= 5mA to 400mA (L4808)
7.50
8.00
8.50
V
I
O
= 5mA to 400mA (L4810)
8.00
8.50
9.00
V
I
O
= 5mA to 400mA (L4812)
8.65
9.20
9.75
V
I
O
= 5mA to 400mA (L4885)
9.40
10.00
10.60
V
I
O
= 300mA (L4892)
11.30
12.00
12.70
V
V
I
Operating Input Voltage
see note 2
26
V
V
O
/V
O
Line Regulation
VI = 14 to 26V; I
O
= 5mA
2
15
mV/V
V
O
/V
O
Load Regulation
IO = 5 to 400mA*
5
25
mV/V
V
I
- V
O
Dropout Voltage
I
O
= 400mA*
0.5
0.9
V
I
O
= 150mA
0.25
0.5
V
I
q
Quiescent Current
I
O
= 0mA
1.2
3
mA
I
O
= 150mA
40
70
mA
I
O
= 400mA*
80
140
mA
I
O
Max Output Current
870
mA
I
SC
Output Short Circuit Current
(fold back condition)
230
mA
L4805-L4808-L4885-L4892-L4810-L4812
3/7
Figure 5: Preregulator for Distributed Supplies
Figure 1: Dropout Voltage vs. Output Current
Figure 2: Quiescent Current vs. Output Current
Figure 3: Output Voltage vs. Temperature
Figure 4: Foldback Current Limiting(L4805)
L4805-L4808-L4885-L4892-L4810-L4812
4/7
SOT82 PACKAGE MECHANICAL DATA
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
7.4
7.8
0.291
0.307
B
10.5
10.8
0.413
0.425
b
0.7
0.9
0.028
0.035
b1
0.49
0.75
0.019
0.030
C
2.4
2.7
0.094
0.106
c1
1.2
0.047
D
15.7
0.618
e
2.2
0.087
e3
4.4
0.173
F
3.8
0.150
H
2.54
0.100
L4805-L4808-L4885-L4892-L4810-L4812
5/7
TO220 PACKAGE MECHANICAL DATA
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
4.8
0.189
C
1.37
0.054
D
2.4
2.8
0.094
0.110
D1
1.2
1.35
0.047
0.053
E
0.35
0.55
0.014
0.022
F
0.8
1.05
0.031
0.041
F2
1.15
1.4
0.045
0.055
G
4.95
5.08
5.21
0.195
0.200
0.205
H2
10.4
0.409
H3
10.05
10.4
0.396
0.409
L2
16.2
0.638
L3
26.3
26.7
27.1
1.035
1.051
1.067
L5
2.6
3
0.102
0.118
L6
15.1
15.8
0.594
0.622
L7
6
6.6
0.236
0.260
Dia
3.65
3.85
0.144
0.152
L4805-L4808-L4885-L4892-L4810-L4812
6/7
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics 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 SGS-THOMSON Microelectronics. Specifica-
tions mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information pre-
viously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or
systems without express written approval of SGS-THOMSON Microelectronics.
1994 SGS-THOMSON Microelectronics - All Rights Reserved
SGS-THOMSON Microelectronics GROUP OF COMPANIES
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L4805-L4808-L4885-L4892-L4810-L4812
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