A8188: Low-Dropout Regulators -- High Efficiency

PRELIMINARY INFORMATION
LOW-DROPOUT REGULATORS
— HIGH EFFICIENCY
(subject to change without notice)
July 13, 1999
Designed specifically to meet the requirement for extended operation of battery-powered equipment such as cordless and cellular telephones, the A8188S— voltage regulators offer the reduced dropout
voltage and quiescent current essential for maximum battery life.
Applicable also to palmtop computers and personal data assistants,
these devices deliver a regulated output at up to 250 mA (transient),
which is limited only by package power dissipation. Regulated output
voltages between 2.5 V and 3.3 V are trimmed at wafer probe.
A8188SLT-xx
T
C
U
Y
D
L
O
N
R
P EO
D
C
E
N
U
E
N
R
I
E
T
F
N
E
O
R
C
S OR
I
D F
—
GND
3
OUT
2
IN
VR
1
Data Sheet
27468.8
8188
Dwg. PS-022-2
where “-xx” is the required output voltage in tenths
ABSOLUTE MAXIMUM RATINGS
Input Voltage, VI . . . . . . . . . . . . . . 10 V
Peak Output Current,
IOM . . . . . . . . . . . . . . . . . . 250 mA*
Enable Input Voltage, VE . . . . . . . . . VI
Operating Temperature Range,
TA . . . . . . . . . . . . . -20°C to +85°C
Junction Temperature, TJ . . . . +150°C†
Storage Temperature Range,
TS . . . . . . . . . . . . -40°C to +150°C
* Output current rating is limited by input
voltage, duty cycle, and ambient temperature. Under any set of conditions, do not
exceed a junction temperature of +150°C.
See following pages.
† Fault conditions that produce excessive
junction temperature will activate device
thermal shutdown circuitry. These conditions can be tolerated but should be
avoided.
A PMOS pass element provides a typical dropout voltage of only
90 mV at 60 mA of load current. The low dropout voltage permits
deeper battery discharge before output regulation is lost. Quiescent
current does not increase significantly as the dropout voltage is approached, an ideal feature in standby/resume power systems where data
integrity is crucial. Regulator accuracy and excellent temperature
characteristics are provided by a bandgap reference. The A8188SL-xx
includes ENABLE inputs to give the designer complete control over
power up, standby, or power down.
These devices are supplied, without the ENABLE function, in a
standard 3-lead SOT-89/TO-243AA small-outline plastic transistor
package (suffix ‘LT’). Dual regulators (A8188SL-xx) are provided in
an 8-lead SOIC package. All devices are rated for operation over a
temperature range of -20°C to +85°C.
FEATURES AND BENEFITS
■ High Efficiency Provides Extended Battery Life
■ 90 mV Typical Dropout Voltage at IO = 60 mA
■ 55 µA Typical Quiescent Current
Less Than 1 µA “Sleep” Current
■ 250 mA Peak Output Current
■ Improved PSRR and Transient Performance
■ Internal Thermal Protection
APPLICATIONS
■
■
■
■
Cordless and Cellular Telephones
Personal Data Assistants
Personal Communicators
Palmtop Computers
Always order by complete part number, e.g., A8188SLT-30 .
8188
LOW-DROPOUT
REGULATORS
FUNCTIONAL BLOCK DIAGRAM
(1/2 of A8188SL-xx shown)
IN
8
1
ENABLE
7
DRIVE
ERROR
AMP
ENABLE
BIAS
2
OUT
BANDGAP
REF.
GND
Dwg. FS-012-8
Always order by complete part number:
Part Number
A8188SL-xx
A8188SLT-xx
Package
8-Lead SOIC
3-Lead SOT-89/TO-243AA
RθJA
108°C/W
258°C/W
A8188SL-xx
where “-xx” is the required output voltage (VO(nom)) in tenths
(25 through 33), e.g., -30 = 3.0 volts.
8
IN
2
7
ENABLE
OUT
2
3
6
IN
GND
2
4
5
ENABLE
2
OUT
1
1
1
VR
GND
1
1
2
VR
Dwg. PS-023
NOTE — There is an indeterminate resistance between terminals
2 and 4. For proper operation, terminals 2 and 4 must be
externally connected together.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 1999, 2000 Allegro MicroSystems, Inc.
8188
LOW-DROPOUT
REGULATORS
A8188SL-xx Maximum Allowable Total Average Output Current* with device mounted on 2.24" x
2.24" (56.9 mm x 56.9 mm) solder-coated copper-clad board in still air.
Allowable Total Average (10 ms) Output Current in Milliamperes with TJ = 150°C, Duty Cycle = 100%†
VI - VO
TA
1.0
1.5
2.0
2.5
3.0
4.0
5 .0
6.0
7.0*
25°C
500
500
500
460
385
285
230
190
165
50°C
500
500
460
370
305
230
185
150
130
70°C
500
490
370
295
245
185
145
120
105
85°C
500
400
300
240
200
150
120
100
85
* Absolute maximum peak output current rating for either output is 250 mA; absolute maximum input voltage is 10 V.
† IO = (TJ – TA)/([VI – VO] RθJA x dc) = (150 – TA)/([VI – VO] x 108 x 1.00)
Output current rating can be increased (to 250 mA maximum per output) by additional heat sinking or reducing the duty
cycle. Conditions that produce excessive junction temperature will activate device thermal shutdown circuitry. These
conditions can be tolerated but should be avoided.
A8188SLT-xx Maximum Allowable Output Current with device mounted on 2.24" x 2.24" (56.9 mm
x 56.9 mm) solder-coated copper-clad board in still air.
Allowable Average (10 ms) Output Current in Milliamperes with TJ = 150°C, Duty Cycle = 100%†
VI - VO
TA
1.0
1.5
2.0
2.5
3.0
4.0
5.0
6.0
7.0*
25°C
250
250
240
190
160
120
95
80
65
50°C
250
250
190
155
125
95
75
65
55
70°C
250
205
155
120
100
75
60
50
40
85°C
250
165
125
100
80
60
50
40
35
* Absolute maximum input voltage is 10 V.
† IO = (TJ – TA)/([VI – VO] RθJA x dc) = (150 – TA)/([VI – VO] x 258 x 1.00)
Output current rating can be increased (to 250 mA maximum) by additional heat sinking or reducing the duty cycle.
Conditions that produce excessive junction temperature will activate device thermal shutdown circuitry. These conditions
can be tolerated but should be avoided.
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8188
LOW-DROPOUT
REGULATORS
ELECTRICAL CHARACTERISTICS at TA = +25°C (unless otherwise noted).
Limits
Characteristic
Symbol
Output Voltage
VO
(reference specified VO(nom))
Output Volt. Temp. Coeff.
aVO
Test Conditions
Min.
Typ.
Max.
Units
4 V ≤ VI ≤ 8 V, 10 µA ≤ IO ≤ 100 mA*
-0.05
0.00
+0.05
V
VI = VO(nom), IO = 60 mA
-0.30
—
—
V
VI = 6 V, IO = 10 mA, TJ ≤ 125°C
—
-0.30
—
mV/°C
Line Regulation
∆VO(∆VI)
4 V ≤ VI ≤ 8 V, IO = 1 mA
—
—
10
mV
Load Regulation
∆VO(∆IO)
1 mA ≤ IO ≤ 100 mA*, VI = 8 V
—
—
40
mV
1 mA ≤ IO ≤ 100 mA*, VI = 6 V
—
—
40
mV
1 mA ≤ IO ≤ 100 mA*, VI = 4 V
—
—
40
mV
IO = 60 mA
—
90
150
mV
IO = 125 mA*
—
190
300
mV
VI = 8 V, IO ≤ 1 mA, VE ≥ 2.0 V
—
55
70
µA
VI = 8 V, IO ≤ 100 mA*, VE ≥ 2.0 V
—
70
85
µA
VI = VO(nom), IO = 60 mA
—
200
—
µA
IQ(off)
4 V ≤ VI ≤ 8 V, VE ≤ 0.8 V
—
—
1.0
µA
VEH
4 V ≤ VI ≤ 8 V, Output ON
2.0
—
—
V
VEL
4 V ≤ VI ≤ 8 V, Output OFF
—
—
0.8
V
VE = VI = 8 V
—
—
±1.0
µA
150
—
—
°C
f = 1 kHz
—
60
—
dB
f = 10 kHz
–
50
—
dB
—
2.0
—
µV/√Hz
Dropout Voltage
Quiescent Current
VImin – VO
IQ
(GND terminal current)
ENABLE Input Voltage
ENABLE Input Current
IE
Thermal Shutdown Temp.
TJ
Rejection Ratio
Noise
PSRR
en
VI = VO(nom) + 1.5 V, Vi = 100 mV, IO = 10 mA:
10 Hz ≤ f ≤ 100 kHz, IO = 10 mA, CO = 10 µF
Typical values are at TA = +25°C and are given for circuit design information only.
* Pulse test (≤20 ms). See previous page for duty cycle limitations.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
8188
LOW-DROPOUT
REGULATORS
TYPICAL CHARACTERISTICS
LINE REGULATION
+0.06
+0.03
+0.04
+0.02
OUTPUT VOLTAGE in VOLTS
OUTPUT VOLTAGE in VOLTS
LOAD REGULATION
+0.02
VI = 8 V
VI = 6 V
VO(nom)
-0.02
V =4V
I
-0.04
TA = -20°C
-0.06
TA = -20°C
50 mA INTERVALS
+0.01
I O = 0 mA
VO(nom)
IO = 100 mA
-0.01
-0.02
-0.03
-0.04
-0.08
0
25
50
75
125
100
2.0
150
3.0
4.0
5.0
7.0
6.0
Dwg. GP-053-13
+0.06
+0.03
+0.04
+0.02
OUTPUT VOLTAGE in VOLTS
OUTPUT VOLTAGE in VOLTS
Dwg. GP-052-13
+0.02
V
VI = 8 V
O(nom)
-0.02
V =4V
I
-0.04
TA = 25°C
-0.06
8.0
INPUT VOLTAGE in VOLTS
OUTPUT CURRENT in mA
TA = 25°C
50 mA INTERVALS
+0.01
IO = 0 mA
V O(nom)
-0.01
I = 100 mA
O
-0.02
-0.03
2 V INTERVALS
-0.04
-0.08
0
25
50
75
100
125
150
2.0
3.0
4.0
5.0
6.0
7.0
8.0
INPUT VOLTAGE in VOLTS
OUTPUT CURRENT in mA
Dwg. GP-052-14
Dwg. GP-053-14
CAUTION: Maximum allowable duty cycle will be significantly less than 100% at high temperatures, at high input voltages, or at high output
currents. See appropriate Maximum Allowable Output Current table.
www.allegromicro.com
8188
LOW-DROPOUT
REGULATORS
TYPICAL CHARACTERISTICS (cont’d)
LINE REGULATION
+0.06
+0.03
+0.04
+0.02
OUTPUT VOLTAGE in VOLTS
OUTPUT VOLTAGE in VOLTS
LOAD REGULATION
+0.02
V
O(nom)
VI = 7 V
VI = 6 V
-0.02
-0.04
VI = 4 V
TA = 85°C
-0.06
TA = 85°C
50 mA INTERVALS
+0.01
V
O(nom)
IO = 0 mA
-0.01
-0.02
IO = 100 mA
-0.03
-0.04
-0.08
0
10
20
30
50
40
60
2.0
OUTPUT CURRENT in mA
3.0
4.0
5.0
6.0
7.0
8.0
INPUT VOLTAGE in VOLTS
Dwg. GP-053-15
Dwg. GP-052-15
OUTPUT VOLTAGE
3.5
V O(nom)
OUTPUT VOLTAGE in VOLTS
OUTPUT VOLTAGE in VOLTS
3.0
2.5
2.0
1.5
I O = 0 - 100 mA
1.0
TA = 25°C
VI = 6 V
+0.01
IO = 0
VO(nom)
-0.01
-0.02
0.5
0
0
1.0
2.0
3.0
4.0
-50
0
+50
+100
AMBIENT TEMPERATURE in °C
INPUT VOLTAGE in VOLTS
Dwg. GP-059-2
Dwg. GP-050-3
CAUTION: Maximum allowable duty cycle will be significantly less than 100% at high temperatures, at high input voltages, or at high output
currents. See appropriate Maximum Allowable Output Current table.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
8188
LOW-DROPOUT
REGULATORS
TYPICAL CHARACTERISTICS (cont’d)
QUIESCENT (GROUND TERMINAL) CURRENT
QUIESCENT (GROUND TERMINAL) CURRENT in µA
QUIESCENT (GROUND TERMINAL) CURRENT in µA
250
60
VI = 6 V
I
=0
O
VE ≥ 2 V
55
50
45
-50
0
+100
+50
200
IO = 0
TA = 25°C
150
100
50
0
-2.0
V O(nom)
AMBIENT TEMPERATURE in °C
+2.0
+4.0
+6.0
INPUT VOLTAGE in VOLTS
Dwg. GP-058-1
Dwg. GP-051-3
DROPOUT VOLTAGE
0.25
DROPOUT VOLTAGE in VOLTS
0.20
TA = 85°C
TA = 25°C
TA = -20°C
0.15
0.10
0.05
0
0
25
50
75
100
125
150
OUTPUT CURRENT in mA
Dwg. GP-054-2
CAUTION: Maximum allowable duty cycle will be significantly less than 100% at high temperatures, at high input voltages, or at high output
currents. See appropriate Maximum Allowable Output Current table.
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8188
LOW-DROPOUT
REGULATORS
TYPICAL CHARACTERISTICS (concluded)
LOAD TRANSIENT PERFORMANCE
ENABLE TRANSIENT PERFORMANCE
VI = 3.2 V to 6.2 V, CO = 4.7 µF, TA = 25°C
VI = 3.2 V to 6.2 V, CO = 1 µF, TA = 25°C
+0.1 V
VO(nom)
VO(nom)
-0.1 V
15 µs
5 µs
VO
0
<100 µs
<150 µs
VI
100 mA
VE
IO
1 mA
0
Dwg. WP-028-2
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Dwg. WP-027-3
8188
LOW-DROPOUT
REGULATORS
A8188SL-xx
Dimensions in Inches
(for reference only)
8
0.0098
0.0075
0.1574
0.1497
0.020
0.013
0.2440
0.2284
1
0.050
0.050
0.016
0° TO 8°
BSC
0.1968
0.1890
0.0688
0.0532
0.0040 MIN.
Dwg. MA-007-8 in
Dimensions in Millimeters
(controlling dimensions)
8
0.25
0.19
4.00
3.80
0.51
0.33
6.20
5.80
1.27
1
BSC
1.27
0.40
0° TO 8°
5.00
4.80
1.75
1.35
0.10 MIN.
NOTES: 1. Lead spacing tolerance is non-cumulative.
2. Exact body and lead configuration at vendor’s option within limits shown.
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Dwg. MA-007-8 mm
8188
LOW-DROPOUT
REGULATORS
A8188SLT-xx
Dimensions in Inches
(for reference only)
0.173
0.181
0.064
0.072
0.155
0.167
1
2
0.055
0.063
3
0.090
0.102
0.014
0.017
0.084
0.090
0.014
0.019
0.017
0.022
0.035
0.047
0.059
BSC
0.118
BSC
Dwg. MA-009-3 in
Dimensions in Millimeters
(controlling dimensions)
4.40
4.60
1.62
1.83
3.94
4.25
1
2
1.40
1.60
3
2.29
2.60
0.35
0.44
2.13
2.29
0.36
0.48
0.89
1.20
0.44
0.56
1.50
BSC
3.00
BSC
Dwg. MA-009-3 mm
NOTES: 1. Lead spacing tolerance is non-cumulative.
2. Exact body and lead configuration at vendor’s option within limits shown.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
8188
LOW-DROPOUT
REGULATORS
this page is intentionally left blank
www.allegromicro.com
8188
LOW-DROPOUT
REGULATORS
Allegro MicroSystems, Inc. reserves the right to make, from time to
time, such departures from the detail specifications as may be required
to permit improvements in the design of its products.
The information included herein is believed to be accurate and
reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of
third parties which may result from its use.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
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