ADP1111
REV.A 3
ABSOLUTE MAXIMUM RATINGS
Parameter Rating
Supply Voltage 36 V
SW1 Pin Voltage 50 V
SW2 Pin Voltage −0.5 V to V
IN
Feedback Pin Voltage (ADP1111) 5.5 V
Switch Current 1.5 A
Maximum Power Dissipation 500 mW
Operating Temperature Range
ADP1111A 0°C to 70°C
Storage Temperature Range −65°C to +150°C
Lead Temperature (Soldering, 10 sec) 300°C
TYPICAL APPLICATION
10µF
(OPTIONAL)
I
LIM
V
IN
SW1
SW2GND
ADP1111AR-5
SUMID
CD54-220K
22µH
5V
100mA
33µF
SENSE
3V
INPUT
MBRS120T3
Figure 1. 3 V to 5 V Step-Up Converter
ESD CAUTION
PIN DESCRIPTIONS
Mnemonic Function
I
LIM
For normal conditions this pin is connected to V
IN
.
When lower current is required, a resistor should be
connected between I
LIM
and V
IN
. Limiting the switch
current to 400 mA is achieved by connecting a 220 Ω
resistor.
V
IN
Input Voltage.
SW1
Collector Node of Power Transistor. For step-down
con-figuration, connect to V
IN
. For step-up configu-
ration, connect to an inductor/diode.
SW2
Emitter Node of Power Transistor. For step-down
configuration, connect to inductor/diode. For step-up
configuration, connect to ground. Do not allow this
pin to go more than a diode drop below ground.
GND Ground.
AO
Auxiliary Gain (GB) Output. The open collector can
sink 300 μA. It can be left open if unused.
SET
Gain Amplifier Input. The amplifier’s positive input is
connected to SET pin and its negative input is con-
nected to the 1.25 V reference. It can be left open if
unused.
FB/SENSE
On the ADP1111 (adjustable) version this pin is con-
nected to the comparator input. On the ADP1111-3.3,
ADP1111-5 and ADP1111-12, the pin goes directly
to the internal application resistor that sets output
voltage.
PIN CONFIGURATIONS
A0
I
LIM
W1
GND
V
IN
W2
*FIXED VERSIONS
FB (SENSE)*
SET
1
2
3
4
8
7
6
5
ADP1111
TOP VIEW
(Not to Scale)
8-Lead Plastic DIP
(N-8)
A0
I
LIM
SW1
GND
V
IN
SW2
*FIXED VERSIONS
FB (SENSE)
SET
1
2
3
4
8
7
6
5
ADP1111
TOP VIEW
(Not to Scale)
8-Lead Plastic SOIC
(SO-8)
