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. Typical 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
IQ1
IQ2
IQ3
V
FB
I
B-FB
V
DD
D
MAX
-600kHz
D
MAX
-1.2MHz
I
LIM
I
SHDN
R
DS-ON
I
LX-LEAK
∆V
OUT
/∆V
IN
∆V
OUT
/∆I
OUT
F
OSC1
F
OSC2
V
IL
V
IH
G
M
A
V
V
DD-ON
V
DD-OFF
I
SS
R
CS
OTP
V
IN
= 3.3V, V
OUT
= 12V, I
OUT
= 0mA, FSEL = GND, T
A
= 25°C unless otherwise specified.
DESCRIPTION
CONDITIONS
SHDN = 0V
SHDN = V
DD
, FB = 1.3V
SHDN = V
DD
, FB = 1.0V
1.272
MIN
TYP
0.6
0.7
1.3
1.294
0.01
2.6
FSEL = 0V
FSEL = V
DD
84
84
1.3
SHDN = 0V
V
DD
= 2.7V, I
LX
= 1A
VSW = 18V
3V < V
IN
< 5.5V, V
OUT
= 12V
V
IN
= 3.3V, V
OUT
= 12V, I
O
= 30mA to 200mA
FSEL = 0V
FSEL = V
DD
500
1000
90
90
1.5
0.01
0.2
0.01
0.1
6.7
620
1250
740
1500
0.5
2.7
∆I
= 5µA
90
130
350
2.40
2.20
4
2.51
2.30
6
0.08
130
2.60
2.40
8
170
3
0.1
2
1.309
0.5
5.5
MAX
10
UNIT
µA
mA
mA
V
µA
V
%
%
A
µA
Ω
µA
%
mV/A
kHz
kHz
V
V
1µ/Ω
V/V
V
V
µA
V/A
°C
Quiescent Current - Shut-down
Quiescent Current - Not Switching
Quiescent Current - Switching
Feedback Voltage
Feedback Input Bias Current
Start-Up Input Voltage Range
Maximum Duty Cycle
Maximum Duty Cycle
Current Limit - Max Peak Input Current
Shut-down Input Bias Current
Switch ON Resistance
Switch Leakage Current
Line Regulation
Load Regulation
Switching Frequency Accuracy
Switching Frequency Accuracy
SHDN, FSEL Input Low Level
SHDN, FSEL Input High Level
Error Amp Tranconductance
Voltage Gain
V
DD
UVLO On Threshold
V
DD
UVLO Off Threshold
Soft-start Charge Current
Current Sense Transresistance
Over Temperature Protection
2
FN7333.3
EL7516
Block Diagram
FSEL
SHDN
SS
VDD
REFERENCE
GENERATOR
OSCILLATOR
SHUTDOWN &
START-UP
CONTROL
LX
PWM LOGIC
CONTROLLER
COMPARATOR
FET
DRIVER
CURRENT
SENSE
GND
FB
GM
AMPLIFIER
COMP
Pin Descriptions
PIN NUMBER
1
2
3
4
5
6
7
8
PIN NAME
COMP
FB
SHDN
GND
LX
VDD
FSEL
SS
DESCRIPTION
Compensation pin. Output of the internal error amplifier. Capacitor and resistor from COMP pin to ground.
Voltage feedback pin. Internal reference is 1.294V nominal. Connect a resistor divider from V
OUT
. V
OUT
=
1.294V (1 + R
1
/ R
2
). See Typical Application Circuit.
Shutdown control pin. Pull SHDN low to turn off the device.
Analog and power ground.
Power switch pin. Connected to the drain of the internal power MOSFET.
Analog power supply input pin.
Frequency select pin. When FSEL is set low, switching frequency is set to 620kHz. When connected to
high or V
DD
, switching frequency is set to 1.25MHz.
Soft-start control pin. Connect a capacitor to control the converter start-up.