Philips Semiconductors
Product data
CMOS switching regulator (PWM controlled)
SA57254-XX
GENERAL DESCRIPTION
The SA57254-XX is a fully integrated DC/DC converter circuit.
Efficient, compact power conversion is achieved with a pulse width
modulation (PWM) controlled switching regulator circuit designed
using CMOS processing. Low ripple and high efficiency of typically
83% are achieved through PWM control. The regulator has a high
precision output with
±2.4%
accuracy. Few external components are
required.
The SA57254-XX has a built-in soft-start circuit which reduces
inrush current and voltage overshoot during start-up. A low
resistance CMOS power FET, which has low leakage current and
low parasitic capacitance, is on-chip.
FEATURES
•
Operates from 0.7 to 9 V
DC
•
Ultra low operating supply current—typically 17
µA
•
Built-in power FET
•
High efficiency—typically 83%
•
High precision output—typically
±2.4%
•
Operating temperature range of –40 to +85
°C
•
Available output voltages: 2.0, 2.5, 2.8, 3.0, 3.3, 3.6, 5.0 V
DC
•
Available in a 5-lead small outline surface mount package
(SOP003)
APPLICATIONS
•
Mobile and portable phones
•
Instrumentation and industrial products
•
Other portable, battery-operated equipment
SIMPLIFIED SYSTEM DIAGRAM
V
OUT
SW 5
V
DD
2
FB 1
V
BATT
SA57254-XX
V
REF
R
PWM CONTROL
R
GND
4
SOFT START
SA57254-XX as a boost (step-up) converter.
Figure 1. Simplified system diagram.
SL01501
2003 Nov 11
2
Philips Semiconductors
Product data
CMOS switching regulator (PWM controlled)
SA57254-XX
ORDERING INFORMATION
PACKAGE
TYPE NUMBER
SA57254-XXGW
NAME
SOT23-5,
SOT25, SO5
DESCRIPTION
Plastic small outline package; 5 leads; body width 1.6 mm
VERSION
SOP003
TEMPERATURE
RANGE
–40 to +85
°C
NOTE:
The device has seven voltage output options, indicated by the
XX
on the Type Number.
XX
20
25
28
30
33
36
50
VOLTAGE (Typical)
2.0 V
2.5 V
2.8 V
3.0 V
3.3 V
3.6 V
5.0 V
Part number marking
Each device is marked with a four letter code. The first three letters
designate the product. The fourth letter, represented by ‘x’, is a date
tracking code.
Part number
SA57254-20GW
SA57254-25GW
SA57254-28GW
SA57254-30GW
SA57254-33GW
SA57254-36GW
SA57254-50GW
Marking
AEKx
AELx
AEMx
AENx
AEPx
AERx
AESx
PIN CONFIGURATION
PIN DESCRIPTION
PIN
SA57254-XX
SYMBOL
FB
V
DD
N/C
GND
SW
DESCRIPTION
Feedback from the output voltage to the PWM
control.
Voltage input to regulator.
No connection.
Ground.
Switching output to inductor.
1
2
3
4
GND
FB
1
5
SW
V
DD
2
N/C
3
4
5
SL01502
Figure 2. Pin configuration.
MAXIMUM RATINGS
SYMBOL
V
IN(max)
V
FB
V
SW
I
SW
T
oper
T
stg
P
D
Power supply voltage
FB pin voltage
SW pin voltage
SW pin current
Operating temperature
Storage temperature
Power dissipation
PARAMETER
MIN.
–0.3
–0.3
–0.3
–
–40
–40
–
MAX.
11
11
11
300
+85
+125
150
UNIT
V
V
V
mA
°C
°C
mW
2003 Nov 11
3
Philips Semiconductors
Product data
CMOS switching regulator (PWM controlled)
SA57254-XX
ELECTRICAL CHARACTERISTICS
T
amb
= 25
°C,
unless otherwise specified.
SYMBOL
V
IN
V
ST1
V
ST2
V
HLD
I
SS1
PARAMETER
input voltage
operating start voltage
oscillator start voltage
operation hold voltage
consumption current 1
I
OUT
= 1.0 mA
V
OUT
= output voltage
×
0.95
I
OUT
= 1.0 mA
CONDITIONS
Part #
–
–
–
–
-20
-25
-28
-30
-33
-36
-50
I
SS2
consumption current 2
V
OUT
= output voltage + 0.5 V
-20
-25
-28
-30
-33
-36
-50
R
DS(ON)
( )
internal switch-on resistance
V
SW
= 0.4 V
-20
-25
-28
-30
-33
-36
-50
I
SWO
∆V
OUT2
∆V
OUT
/∆T
amb
f
OSC
MaxDuty
t
SS
E
FFI
switching transistor leak
current
load ripple voltage
output voltage temperature
coefficient
oscillator frequency
maximum duty ratio
soft start time
efficiency
V
OUT
= V
SW
= 9 V
I
OUT
= 10 mA
≈
I
OUT
(following)
×
1.25
–40
°C ≤
T
amb
≤
+85
°C
V
OUT
= output voltage
×
0.95
V
OUT
= output voltage
×
0.95
I
OUT
= 1.0 mA
–
–
–
–
–
–
-20
-25
-28
-30
-33
-36
-50
MIN.
–
–
–
0.7
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
42.5
75
3.0
–
–
–
–
–
–
–
TYP.
–
–
–
–
11.6
14.3
16.1
17.2
19.1
22.4
38.5
3.1
3.2
3.2
3.2
3.3
3.3
3.5
5.6
4.1
4.1
3.2
3.2
3.2
2.2
–
30
±50
50
83
6.0
75
79
79
83
83
83
87
MAX.
9.0
0.9
0.8
–
19.4
23.9
26.8
28.7
31.8
37.3
64.1
6.2
6.3
6.4
6.4
6.5
6.5
6.9
8.9
6.5
6.5
5.1
5.1
5.1
3.5
1.0
60
–
57.5
90
12
–
–
–
–
–
–
–
UNIT
V
V
V
V
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
Ω
Ω
Ω
Ω
Ω
Ω
Ω
µA
mV
ppm/°C
kHz
%
ms
%
%
%
%
%
%
%
2003 Nov 11
4
Philips Semiconductors
Product data
CMOS switching regulator (PWM controlled)
SA57254-XX
TYPICAL PERFORMANCE CURVES
50
V
OUT
= OUTPUT VOLTAGE
×
0.95
40
4
5
V
OUT
= OUTPUT VOLTAGE + 0.5 V
30
I
SS1
(µA)
20
I
SS2
(µA)
3
2
10
1
0
–40
–20
0
20
40
60
80
100
0
–40
–20
0
20
40
60
80
100
T
amb
〈°C)
T
amb
〈°C)
SL01456
SL01457
Figure 3. Supply current 1 versus temperature.
Figure 4. Supply current 2 versus temperature.
70
V
OUT
= OUTPUT VOLTAGE
×
0.95
65
50
T
amb
= 25
°C
40
60
55
f
OSC
(kHz)
50
45
40
35
30
–40
0
–20
0
20
40
60
80
100
0
2
4
V
OUT
(V)
6
8
10
T
amb
〈°C)
10
I
SS1, 2
(µA)
20
30
SL01458
SL01459
Figure 5. Oscillator frequency versus temperature.
Figure 6. Supply current 1, 2 versus V
OUT
.
250
70
T
amb
= 25
°C
V
CONT
= 0.4 V
60
T
amb
= 25
°C
200
150
I
SW
(mA)
100
f
OSC
(kHz)
50
50
40
0
0
1
2
V
OUT
(V)
3
4
5
30
0
1
2
V
OUT
(V)
3
4
5
SL01462
SL01471
Figure 7. Typical switch current versus V
OUT
.
Figure 8. Oscillator frequency versus V
OUT
.
2003 Nov 11
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