very low drop voltage regulators
L4805-L4885-L4892
L4808-L4810-L4812
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
DESCRIPTION
L4800 series devices are voltage regulators with a
very low voltage drop (typically 0.4V at full rated current), output current up to 400mA, low quiescent
current and comprehensiveon-chip protection.These 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 and12V versions (all± 4%, TI = 25°C) these regulators are designed for automotive, industrial
and consumer applications where low consumption
is particularly important.
SO T-82
TO-220
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.
BLOCK DIAGRAM
March 1992
1/7
L4805-L4808-L4885-L4892-L4810-L4812
ABSOLUTE MAXIMUM RATINGS
Symbol
VI
Value
Unit
DC Input Voltage
Parameter
+ 35
V
DC Input Reverse Voltage
- 18
V
60
V
- 60
V
- 55 to + 150
°C
Transient Input Overvoltages :
Load Dump :
5ms < Trise < 10ms,
τf Fall Time Constant = 100ms,
R source < 0.5Ω
Field Decay :
5ms < tfall < 10ms, Rsource < 10Ω
τr Rise Time Constant = 33ms
Tj, Tstg
Junction and Storage Temperature Range
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)
Order Codes
TO-220
L4805CV
L4808CV
L4885CV
L4892CV
L4810CV
L4812CV
SOT-82
L4805CX
L4808CX
L4885CX
L4892CX
L4810CX
L4812CX
Output Voltage
5V
8V
8.5 V
9.2 V
10 V
12 V
TEST AND APPLICATION CIRCUIT
The output capacitor is required for stability. Though
the 100 µF 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 factors 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 voltages during brief conditions of negative input transients that might be characteristics of a particular
system.
2/7
Capacitors must also be rated at all ambient temperature 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, capacitors rated at that temperature (such as tantalums) must be used.
L4805-L4808-L4885-L4892-L4810-L4812
ELECTRICAL CHARACTERISTICS (VI = 14.4V; CO = 100µF; Tj = 25°C unless otherwise specified.)
Symbol
VO
VI
Parameter
Output Voltage
T est Con di tio n
Min.
Typ.
Max.
Unit
IO = 5mA to 400mA (L4805)
4.80
5.00
5.20
V
IO = 5mA to 400mA (L4808)
7.68
8.00
8.32
V
IO = 5mA to 400mA (L4810)
8.16
8.50
8.84
V
IO = 5mA to 400mA (L4812)
8.83
9.20
9.57
V
IO = 5mA to 400mA (L4885)
9.60
10.00
10.40
V
IO = 300mA (L4892)
11.50
12.00
12.50
V
26
V
Operating Input Voltage
∆VO/VO
Line Regulation
VI = 13 to 26V; IO = 5mA
1
10
mV/V
∆VO/VO
Load Regulation
IO = 5 to 400mA*
3
15
mV/V
VI - VO
Dropout Voltage
IO = 400mA*
0.4
0.7
V
IO = 150mA
0.2
0.4
V
Iq
∆VO
∆T•VO
SVR
Quiescent Current
IO = 0mA
0.8
2
mA
IO = 150mA
25
45
mA
IO = 400mA*
65
90
mA
Temperature Output Voltage
Drift
Supply Voltage Rejection
IO = 350mA; f = 320Hz;
CO = 100µF; VI = VO +3V+2Vpp
0.1
mV
°C•V
60
dB
mA
IO
Max Output Current
800
ISC
Output Short Circuit Current
(fold back condition)
350
500
mA
* only for L4892 the current test conditions is IO = 300mA
ELECTRICAL CHARACTERISTICS (VI = 14.4V; CO = 100µF; Tj = -40 to 125°C (note 1) unless
otherwise specified.)
Symbol
VO
Parameter
Output Voltage
Min.
Typ.
Max.
Unit
IO = 5mA to 400mA (L4805)
T est Con di tio n
4.70
5.00
5.30
V
IO = 5mA to 400mA (L4808)
7.50
8.00
8.50
V
IO = 5mA to 400mA (L4810)
8.00
8.50
9.00
V
IO = 5mA to 400mA (L4812)
8.65
9.20
9.75
V
IO = 5mA to 400mA (L4885)
9.40
10.00
10.60
V
IO = 300mA (L4892)
11.30
12.00
12.70
V
Operating Input Voltage
see note 2
∆VO/VO
Line Regulation
VI = 14 to 26V; IO = 5mA
∆VO/VO
Load Regulation
IO = 5 to 400mA*
VI - VO
Dropout Voltage
IO = 400mA*
IO = 150mA
0.25
0.5
V
IO = 0mA
1.2
3
mA
IO = 150mA
40
70
mA
IO = 400mA*
80
140
mA
VI
Iq
Quiescent Current
26
V
15
mV/V
5
25
mV/V
0.5
0.9
V
2
IO
Max Output Current
870
mA
ISC
Output Short Circuit Current
(fold back condition)
230
mA
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.
3/7
L4805-L4808-L4885-L4892-L4810-L4812
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)
Figure 5: Preregulator for Distributed Supplies
4/7
L4805-L4808-L4885-L4892-L4810-L4812
SOT82 PACKAGE MECHANICAL DATA
mm
DIM.
MIN.
TYP.
inch
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
5/7
L4805-L4808-L4885-L4892-L4810-L4812
TO220 PACKAGE MECHANICAL DATA
mm
DIM.
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
5.21
0.195
5.08
H2
H3
0.200
10.4
10.05
L2
6/7
inch
10.4
0.409
0.396
16.2
L3
26.3
L5
26.7
0.205
0.409
0.638
27.1
1.035
1.051
1.067
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
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. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously 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
Australia - Brazil - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands - Singapore Spain - Sweden - Switzerland - Taiwan - Thaliand - United Kingdom - U.S.A.
7/7
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