CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typ values are for information purposes only. Unless otherwise noted, all tests are
at the specified temperature and are pulsed tests, therefore: T
J
= T
C
= T
A
Electrical Specifications
PARAMETER
DC CHARACTERISTICS
V
FB
I
FB
V
IN
, V
DD
V
IN,OFF
V
IN,ON
I
DD
V
DD
= V
IN
= V
EN
= 3.3V, C1 = C2 = 10µF, L = 1.8µH, V
O
= 1.8V, unless otherwise specified.
CONDITIONS
MIN
TYP
MAX
UNIT
DESCRIPTION
Feedback Input Voltage
Feedback Input Current
Input Voltage
Minimum Voltage for Shutdown
Maximum Voltage for Startup
Supply Current
V
IN
falling
V
IN
rising
PWM, V
IN
= V
DD
= 5V
EN = 0, V
IN
= V
DD
= 5V
790
800
810
250
mV
nA
V
V
V
µA
µA
m
m
A
°C
°C
2.5
2
2.2
400
0.1
70
45
1.5
T rising
T falling
V
EN
, V
RSI
= 0V and 3.3V
V
DD
= 3.3V
V
DD
= 3.3V
V
FB
rising
V
FB
falling
I
SINK
= 5mA
86
35
0.8
-1
145
130
5.5
2.2
2.4
500
1
100
75
R
DS(ON)-PMOS
PMOS FET Resistance
V
DD
= 5V, wafer test only
V
DD
= 5V, wafer test only
R
DS(ON)-NMOS
NMOS FET Resistance
I
LMAX
T
OT,OFF
T
OT,ON
I
EN
, I
RSI
V
EN1
, V
RSI1
V
EN2
, V
RSI2
V
POR
Current Limit
Over-temperature Threshold
Over-temperature Hysteresis
EN, RSI Current
EN, RSI Rising Threshold
EN, RSI Falling Threshold
Minimum V
FB
for POR, WRT Targeted
V
FB
Value
POR Voltage Drop
1
2.4
µA
V
V
95
%
%
V
OLPOR
70
mV
AC CHARACTERISTICS
F
PWM
t
RSI
t
SS
t
POR
PWM Switching Frequency
Minimum RSI Pulse Width
Soft-start Time
Power On Reset Delay Time
80
Guaranteed by design
1.4
1.5
25
650
100
120
1.75
50
MHz
ns
µs
ms
FN7431 Rev 8.00
July 12, 2006
Page 2 of 9
EL7534
Pin Descriptions
PIN NUMBER
1
2
3
4
5
6
7
8
9
10
PIN NAME
SGND
PGND
LX
VIN
VDD
RSI
EN
POR
VO
FB
Negative supply for the controller stage
Negative supply for the power stage
Inductor drive pin; high current digital output with average voltage equal to the regulator output voltage
Positive supply for the power stage
Power supply for the controller stage
Resets POR timer
Enable
Power on reset open drain output
Output voltage sense
Voltage feedback input; connected to an external resistor divider between V
O
and SGND for variable
output
PIN FUNCTION
Block Diagram
100
0.1µF
V
DD
V
O
10pF
+
-
CURRENT LIMIT
PWM
COMPEN-
SATION
V
IN
124K
FB
5M
-
+
100K
CLOCK
1.5MHz
EN
EN
SOFT-START
RAMP
GENERATOR
+
-
PWM
COMPARATOR
CONTROL
LOGIC
P-DRIVER
LX
1.8µH
1.8V
600mA
10µF
N-DRIVER
UNDER-
VOLTAGE
LOCKOUT
TEMPERATURE
SENSE
10µF
2.5V-
3.5V
+
–
BANDGAP
REFERENCE
SGND
PGND
100K
POR
PG
RSI
POR
FN7431 Rev 8.00
July 12, 2006
Page 3 of 9
EL7534
Performance Curves and Waveforms
All waveforms are taken at V
IN
= 3.3V, V
O
= 1.8V, I
O
= 600mA with component values shown on page 1 at room ambient temperature, unless
otherwise noted.
100
95
90
EFFICIENCY (%)
85
80
75
70
65
60
V
IN
=5V
V
O
=3.3V
EFFICIENCY (%)
100
95
90
85
80
75
70
65
60
V
IN
=3.3V
V
O
=2.5V
V
O
=1.8V
V
O
=1.2V
V
O
=1V
V
O
=1.8V
0
200
I
O
(mA)
400
600
0
200
I
O
(mA)
400
600
FIGURE 1. EFFICIENCY
FIGURE 2. EFFICIENCY
1.54
1.52
1.5
V
IN
=5V, I
O
=600mA
V
IN
=3.3V, I
O
=600mA
V
IN
=5V, I
O
=0A
V
O
CHANGES
0.1%
0.0%
-0.1%
-0.2%
-0.3%
-0.4%
-0.5%
V
IN
=5V
V
IN
=3.3V
F
S
(MHz)
V
IN
=3.3V, I
O
=0A
1.48
1.46
1.44
1.42
-50
0
50
T
A
(°C)
100
150
0
0.2
0.4
I
O
(A)
0.6
0.8
1
FIGURE 3. F
S
vs JUNCTION TEMPERATURE
FIGURE 4. LOAD REGULATIONS
0.1%
0.0%
-0.1%
V
O
CHANGES
-0.2%
-0.3%
-0.4%
-0.5%
-0.6%
-0.7%
-50
V
IN
=5V I
O
=600mA
0
50
T
J
(°C)
100
150
V
IN
=3.3V I
O
=600mA
I
IN
(mA)
V
IN
=3.3V I
O
=0A
V
IN
=5V I
O
=0A
12
10
8
6
4
2
0
2.5
3
3.5
V
IN
(V)
4
4.5
5
FIGURE 5. LOAD/LINE REGULATIONS vs JUNCTION
TEMPERATURE
FIGURE 6. NO LOAD INPUT CURRENT
FN7431 Rev 8.00
July 12, 2006
Page 4 of 9
EL7534
Performance Curves and Waveforms
(Continued)
All waveforms are taken at V
IN
= 3.3V, V
O
= 1.8V, I
O
= 600mA with component values shown on page 1 at room ambient temperature, unless