3.3 V, 0.5 A Low Dropout Voltage Regulator
with On/Off Function
Overview
The L88MS33T is a low dropout voltage regulator with an
output voltage of 3.3 V (standard), with an on-chip on/off
function to maximize equipment power saving effectiveness.
Because it can operate with a low input-output voltage
difference, it contributes to smaller and more efficient set
power supplies, optimum for audio-visual and office
automation equipment.
Functions
.
Output voltage: 3.3 V
.
On/off control of output voltage by strobe pin (active low)
.
500 mA output current
Features
.
Low minimum input-output voltage differential (0.4 V typ)
enables to save energy and miniaturize transformer size.
.
Quiescent current is low with output off.
.
Set size can be miniaturized with compact TP-5H power
package.
.
Surface mounting on board permits allowable power
dissipation to be raised.
.
Enhanced mount flexibility with range of formed products.
.
On-chip protective circuitry (fold back short circuit, thermal
over load).
.
External noise suppression pin provided.
Package Dimensions
unit : mm
3103-TP-5H
[L88MS33T]
SANYO : TP-5H
Pin Assignment
Top view
Specifications
Maximum Ratings
at Ta = 25C
Parameter
Symbol
Conditions
Ratings
Unit
Input voltage
V
IN
max
18
V
Strobe pin input voltage
V
ST
max
V
IN
max
V
Allowable power dissipation
Pd max
Ta
%
25C, no heat sink
1
W
Tc = 25C, with infinite heat sink
6.25
W
Thermal resistance (junction-atmosphere)
j-a
125
C/W
Thermal resistance (junction-to-case)
j-c
20
C/W
Operating temperature
Topr
20 to +85
C
Storage temperature
Tstg
55 to +150
C
Ordering number: EN5516
Monolithic Linear IC
L88MS33T
SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN
31097HA(II) No.5516-1/7
Operating Conditions
at Ta = 25 C
Parameter
Symbol
Conditions
Ratings
Unit
Input voltage
V
IN
4 to 17
V
Output current
l
OUT
0 to 500
mA
Output on control voltage
V
STL
0.3 to +0.8
V
Output off control voltage
V
STH
2.0 to V
IN
V
Operating Characteristics
at Tj = 25 C, V
IN
= 6.3 V, I
O
= 500 mA, C
OUT
= 100 F, C
IN
,
Cn = 1 F,
see specified Test Circuit.
Parameter
Symbol
Conditions
min
typ
max
Unit
[Output on, V
ST
= ``L'']
Output voltage
V
OUT
3.2
3.3
3.4
V
Dropout voltage
V
DROP1
0.4
0.6
V
V
DROP2
l
O
= 150 mA
0.2
0.3
V
Line regulation
V
OLN
4 V
%
V
IN
%
17 V
10
50
mV
Load regulation
V
OLD
5 mA
%
I
OUT
%
500 mA
24
80
mV
Peak output current
l
OP
600
900
mA
Output short-circuit current
l
OSC
100
300
mA
Quiescent current
I
Q1
I
OUT
= 0
1.9
5
mA
I
Q2
24
50
mA
Output noise voltage
V
NO
10 Hz
%
f
%
100 kHz
30
Vrms
Temperature coefficient of
output voltage
V
OUT
/
Tj
Tj = 25 to 125 C
0.4
mV/C
Ripple rejection
Rrej
f = 120 Hz, 4.3 V
%
V
IN
%
17 V
70
dB
Output on control voltage
V
STL
0.8
V
[Output off, V
ST
= ``H'' ]
Low output voltage
V
O
OFF
V
ST
= 5 V
20
200
mV
Static current
I
Q
OFF
V
ST
= 5 V, Except I
STB
35
70
A
Output off control voltage
V
STH
2.0
V
IN
V
L88MS33T
No.5516-2/7
Equivalent Circuit Block Diagram
Test Circuit
Notes: 1. To ensure operational stability, C
IN
, C
OUT
, and Cn should be placed as close to the IC as possible.
2. Because the output capacitor C
OUT
is set at over 100 F to prevent oscillation at low temperatures, a capacitor that
exhibits little change in capacity with temperature variations should be used (such as a tantalum capacitor).
3. Adding capacitor Cn enables external noise suppression and ripple rejection to be improved. However, attention should
be given to system stability (phase margin).
4. When the strobe (STB) pin is open, output is turned on by internal bias. When the strobe function is not used, the STB
pin should be connected to GND to complete strobe operation.
5. When V
IN
is minus () and GND is plus (+) (reversed connection), excessive current flow will occur.
Start-up
circuit
Reference
voltage
Error
amp
Thermal
protector
Short circuit
protector
ON/OFF
Control
L88MS33T
No.5516-3/7
Function Table
Sample Application Circuit
Adjustment of output voltage V
OUT
(1) Reducing V
OUT
V
OUT
can be lowered by externally connecting a resistor
R
A
between the Cn and V
OUT
pins.
(2) Increasing V
OUT
V
OUT
can be raised by externally connecting a resistor R
B
between the Cn and GND pins.
Control
signal
V
STB
V
OUT
L
H
H
L
On/off Control Input Equivalent Circuit
L88MS33T
No.5516-4/7
1)
The allowable power dissipation is 1.0 W (Ta = 25C) with no fin attached, but when mounted on a hybrid IC board or
printed circuit board, high allowable power dissipation is achieved, despite the compact package. The graph below depicts the
relationship between the copper-clad area and allowable power dissipation when mounted on a glass epoxy board
(50
5 0
0.8 mm
3
) with a copper thickness of 18 m.
2)
Pd is the value for when the solder on the surface of the IC heat sink has melted completely and the surface mount is
horizontal.
3)
Please be advised that the flow solder application system (full-heat method) cannot be recommended.
Lead Formings
Pd max Ta
With infinite heat sink
Mounted on copper-clad
area of 2,000 mm
2
Mounted on copper-clad
area 740 mm
2
Mounted on copper-clad
area 180 mm
2
Mounted on copper-clad
area 36 mm
2
No heat sink
Ambient temperature, Ta C
Allowable
power
dissipation,
Pd
max
W
Pd max S
Board
Copper-clad area S
(mm
2
)
Allowable
power
dissipation,
Pd
max
W
Copper-clad area, S mm
2
MA forming
LR forming
FA forming
L88MS33T
No.5516-5/7
V
O
V
IN
Output
voltage,
V
O
V
V
DROP
I
O
Dropout
voltage,
V
DROP
V
Input voltage, V
IN
V
Output current, I
O
A
Output
voltage,
V
O
V
V
O
I
O
Output current, I
O
A
Output
voltage,
V
O
V
V
O
V
ST
Strobe voltage, V
ST
V
V
STH
, V
STL
Ta
Output
of
f
control
voltage,
V
STH
V
Output
on
control
voltage,
V
STL
V
I
Q
V
IN
Quiescent
current,
I
Q
m
A
Ambient temperature, Ta C
Input voltage, V
IN
V
Quiescent
current,
I
Q
m
A
I
Q
I
O
Output current, I
O
A
Quiescent
current
during
strobe,
I
Q
OFF
m
A
I
Q OFF
V
IN
Input voltage, V
IN
V
(except I
ST
)
L88MS33T
No.5516-6/7
No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment,
nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or
indirectly cause injury, death or property loss.
Anyone purchasing any products described or contained herein for an above-mentioned use shall:
1
Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors
and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and
expenses associated with such use:
2
Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on SANYO
ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally.
Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume
production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use
or any infringements of intellectual property rights or other rights of third parties.
This catalog provides information as of March, 1997. Specifications and information herein are subject to change without notice.
Output
voltage,
V
O
V
V
O
Ta
Ambient temperature, Ta C
Quiescent
current,
I
Q
m
A
I
Q
Ta
Ambient temperature, Ta C
Peak
output
current,
I
OP
A
Output
short-circuit
current,
I
OSC
A
Ambient temperature, Ta C
Quiescent
current
during
strobe,
I
Q
OFF
A
(except I
ST
)
Ambient temperature, Ta C
I
OP
, I
OSC
Ta
I
Q OFF (ST ON)
Ta
Ripple
rejection,
Rrej
d
B
Frequency, f Hz
Cn = 1 F
Cn = open
Rrej f
L88MS33T
No.5516-7/7
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