1/15November 2003
■GLITCH FREE TRANSITION BETWEEN
INPUT SOURCES
■INTERNAL LOGIC SELECTS INPUT
SOURCE
■GATE DRIVE FOR EXTERNAL PMOS
BYPASS SWITCH
■5V DETECTOR WITH HYSTERESIS
■1% 3.3V REGULATED OUTPUT VOLTAGE
■500mA GUARANTEED OUTPUT CURRENT
■OPERATING TEMPERATURE RANGE
FROM 0°C TO 85°C
■AVAILABLE IN P2PAK PACKAGE
■PPAK AND SO-8 PACKAGES CAN BE
AVAILABLE ON REQUEST
APPLICATIONS
■NETWORK INTERFACE CARDS
■PCMCIA/PCI INTERFACE CARDS
■DESKTOP COMPUTERS
■POWER SUPPLY WITH MULTIPLE INPUT
SOURCES
DESCRIPTION
The ST1534A is intended for application such as
power managed PCI and network interface cards
(NICs), where operations from 3.3V VAUX supply
may be required when the 5V supply has been
shut down.
During regular operation, 3.3V power for the PCI
card is provided by the internal LDO regulator,
generated from 5V supply. When the 5V VAUX is
available, the IC connects this supply directly to its
output using an external P-Channel FET. This
ensuresan uninterrupted 3.3V out even if VIN falls
out of specification.
When both supplies are available simultaneously,
the drive pin DR will be pulled high, turning off the
PMOS switch.
The device is available in the popular 5 leads
P2PAK and PPAK
ST1534A
500mA SMART LDO
-
+
-
+
VIN
VIN
DR
VOUT
Reference Error
Amp
5V Detect
Rpull_down
GND
SCHEMATIC DIAGRAM
SO-8
PPAKP2PAK
ST1534A
2/15
ABSOLUTE MAXIMUM RATINGS
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is
not implied.
THERMAL DATA
CONNECTION DIAGRAM (top view)
PIN DESCRIPTION
ORDERING INFORMATION
Symbol Parameter² Value Unit
VIDC Input Voltage -0.3 to 7 V
VSHDN Shutdown Input Voltage -0.3 to 7 V
IOOutput Current Internally limited mA
Tstg Storage Temperature Range -40 to +125 °C
Top Operating Junction Temperature Range 0to+85 °C
Symbol Parameter PPAK P2PAK SO-8 Unit
Rthj-case Thermal Resistance Junction-case 8320°C/W
R
thj-amb Thermal Resistance Junction-ambient 100 50 55 °C/W
SO-8
P2PAK PPAK
Pin PPAK/P2PAK Pin SO/8 Symbol Name and Function
1 1 AUX Auxiliary Input port typically 3.3V
2 2 IN Input port typically 5V
3 5, 6, 7, 8 GND Ground
4 3 OUT LDO 3.3V Output Port
5 4 DR Drive Output for external P-Channel MOSFET pass element
TYPE PPAK P2PAK SO-8
ST1534A ST1534APT-TR ST1534AP2T-R ST1534AD-TR
ST1534A
3/15
TYPICAL APPLICATION CIRCUIT
ELECTRICAL CHARACTERISTICS (Tj=25°C,V
I
=5V, VAUX=3.3V, IO=10mA, CO=2.2µF,
unless otherwise specified)
Note 1: Guaranteed by design
Note 2: See timing diagram
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VIInput Voltage Range 4.5 5 5.5 V
IIN Input Supply Current VI≥4.5V IO= 0mA VAUX =0V 11 mA
V
I≥4.5V IO= 0mA VAUX = 3.3V 11 mA
VI< 4.1V IO= 0mA VAUX =0V 2 mA
V
I< 4.1V IO= 0mA VAUX = 3.3V 2 mA
IAUX Auxiliary Supply Current VI= 0 V 2.2 mA
VI= 5V 200 µA
3.3V VOLTAGE REGULATOR BLOCK
VOOutput Voltage Tj= 0 to 85 °C 3.18 3.3 3.42 V
∆VOLine Regulation VI= 4.5 to 5.5V 0.04 0.5 %
∆VOLoad Regulation IO= 0 to 500mA 0.1 1 %
VdDropout Voltage IO= 500 mA Tj= 0 to 85 °C 1.15 V
IOOutput Current Limit Tj=0to85°C 550 mA
5V DETECT BLOCK
VTHL Low Threshold Voltage VIfalling, IO= 500 mA Tj= 0 to 85 °C 4.15 4.3 V
VHYST Hysteresis 70 200 mV
DRIVE OUTPUT BLOCK
VDR Drive Output Voltage VI= 4.5 to 5.5V IDR =200µA 3.6 VIN-0.8 V
VI< 4.15V IDR =200µA 100 200 mV
IDR Drive Current Sinking: VI= 4.15V VDR = 1V 7 20 mA
Sourcing: VI= 4.5V VI-V
DR = 2V 7 25 mA
tDH Drive High Delay (Note 1
and 2) CDR = 1.2nF, VIN ramping up, measured
from VI=V
TH(H) to VDR = 3.3V
Tj=0to85°C
25µs
t
DL Drive Low Delay (Note 1
and 2) CDR = 1.2nF, VIN ramping down, measured
from VI=V
TH(L) to VDR = 200mV
Tj=0to85°C
36µs
IN GND OUT
DR
4.7 µF 0.1 µF
5V
3.3V
10 µF0.1 µF
Vout=3.3V
0.1 µF
AUX
ST1534A
4/15
5V DETECT THRESHOLDS
VIN rise and fall times (10% to 90%) to be > 100µs
TIMING DIAGRAM
VIN rise and fall times (10% to 90%) to be > 100µs
ST1534A
5/15
TYPICAL CHARACTERISTICS (unless otherwise specified Tj=25°C)
Figure 1 : Supply Current vs Temperature
Figure 2 : Aux Current vs Temperature
Figure 3 : Drive Current vs Temperature
Figure 4 : Aux Current vs Temperature
Figure 5 : Drive Output Voltage vs Temperature
Figure 6 : Drive Current vs VIN-VDR
ST1534A
6/15
Figure 7 : Drive Current vs Temperature
Figure 8 : Line Regulation vs Temperature
Figure 9 : Output Voltage vs Input Voltage
Figure 10 : Output Voltage vs Temperature
Figure 11 : Load Regulation vs Temperature
Figure 12 : Threshold Voltage vs Temperature
ST1534A
7/15
Figure 13 : Hysteresis vs Temperature
Figure 14 : Threshold
Figure 15 : Glitch
Figure 16 : Threshold
Figure 17 : Glitch
Figure 18 : Line Transient
V
I=
3
.5 to
4
.5
V
,t
s
=tf>
100
µs,
I
O=5
00
m
A
,
C
I=
0
.
1
+
4
.7µ
F
,
CO=33+0.1µF
V
I=
3
.5 to 5
V
,
I
O=5
00
m
A
,
C
O=
33
+
0
.
1
µ
F
,w
i
t
hP
-
Ch
anne
l
V
I=
3
.5 to
4
.5
V
,t
s
=tf>
100
µs,
N
o
L
oa
dC
I=
0
.
1
+
4
.7µ
F
,
CO=33+0.1µF
V
I=
3
.5 to 5
V
,
I
O=5
00
m
A
,
C
O=
33
+
0
.
1
µ
F
,w
i
t
hP
-
Ch
anne
l
V
I=
4
.5 to 5.5
V
,
I
O=
10
m
A
,
C
I=
0
.
1
+
4
.7µ
F
,
C
O=
33
+
0
.
1
µ
F
,
CAUX=0.1µF,
ST1534A
8/15
Figure 19 : Load Transient
V
I=5
V
,
I
O=
0
to 5
00
m
A
,
C
I=
4
.7+
0
.
1
µ
F
,
C
O=
0
.
1
+
33
µ
F
,
C
AUX=
0
.
1
µ
F
ST1534A
9/15
DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
A 2.2 2.4 0.086 0.094
A1 0.9 1.1 0.035 0.043
A2 0.03 0.23 0.001 0.009
B 0.4 0.6 0.015 0.023
B2 5.2 5.4 0.204 0.212
C 0.45 0.6 0.017 0.023
C2 0.48 0.6 0.019 0.023
D 6 6.2 0.236 0.244
E 6.4 6.6 0.252 0.260
G 4.9 5.25 0.193 0.206
G1 2.38 2.7 0.093 0.106
H 9.35 10.1 0.368 0.397
L2 0.8 0.031
L4 0.6 1 0.023 0.039
PPAK MECHANICAL DATA
0078180-B
ST1534A
10/15
DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
A 4.30 4.80 0.169 0.188
A2 0.03 0.23 0.001 0.009
C 1.17 1.37 0.046 0.053
D 2.40 2.80 0.094 0.110
D1 8.95 9.35 0.352 0.368
E 0.45 0.60 0.017 0.023
F 0.80 1.05 0.031 0.041
G 3.20 3.60 0.126 0.142
G1 6.60 7.00 0.260 0.275
H1 8.5 0.334 0.409
H2 10.00 10.40 0.393 0.409
L 15 15.85 0.590 0.624
L1 8 0.315
L2 1.27 1.40 0.050 0.055
M 2.4 3.2 0.094 0.126
R 0.40 0.016
V2 0˚ 8˚ 0˚ 8˚
P2PAK/A MECHANICAL DATA
7157127/A
ST1534A
11/15
DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
A 1.35 1.75 0.053 0.069
A1 0.10 0.25 0.04 0.010
A2 1.10 1.65 0.043 0.065
B 0.33 0.51 0.013 0.020
C 0.19 0.25 0.007 0.010
D 4.80 5.00 0.189 0.197
E 3.80 4.00 0.150 0.157
e 1.27 0.050
H 5.80 6.20 0.228 0.244
h 0.25 0.50 0.010 0.020
L 0.40 1.27 0.016 0.050
k ˚ (max.)
ddd 0.1 0.04
SO-8 MECHANICAL DATA
0016023/C
8
ST1534A
12/15
DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
A 330 12.992
C 12.8 13.0 13.2 0.504 0.512 0.519
D 20.2 0.795
N 60 2.362
T 14.4 0.567
Ao 6.80 6.90 7.00 0.268 0.272 0.2.76
Bo 10.40 10.50 10.60 0.409 0.413 0.417
Ko 2.55 2.65 2.75 0.100 0.104 0.105
Po 3.9 4.0 4.1 0.153 0.157 0.161
P 7.9 8.0 8.1 0.311 0.315 0.319
Tape & Reel DPAK-PPAK MECHANICAL DATA
ST1534A
13/15
DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
A 180 7.086
C 12.8 13.0 13.2 0.504 0.512 0.519
D 20.2 0.795
N 60 2.362
T 14.4 0.567
Ao 10.50 10.6 10.70 0.413 0.417 0.421
Bo 15.70 15.80 15.90 0.618 0.622 0.626
Ko 4.80 4.90 5.00 0.189 0.193 0.197
Po 3.9 4.0 4.1 0.153 0.157 0.161
P 11.9 12.0 12.1 0.468 0.472 0.476
Tape & Reel D2PAK-P2PAK-D2PAK/A-P2PAK/A MECHANICAL DATA
ST1534A
14/15
DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
A 330 12.992
C 12.8 13.2 0.504 0.519
D 20.2 0.795
N 60 2.362
T 22.4 0.882
Ao 8.1 8.5 0.319 0.335
Bo 5.5 5.9 0.216 0.232
Ko 2.1 2.3 0.082 0.090
Po 3.9 4.1 0.153 0.161
P 7.9 8.1 0.311 0.319
Tape & Reel SO-8 MECHANICAL DATA
ST1534A
15/15
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the
conseq uences of u se of such inform ation nor fo r an y infr ingeme nt of pa tents or oth er righ ts of third part ies whic h may resul t from
its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications
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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