IL34063A
1
DC-TO-DC CONVERTER CONTROL CIRCUITS
The IL34063Ais a monolithic control circuit containing the primary functions required for DC-to-DC converters.
These devices consist of an internal temperature compensated reference, comparator, controlled duty cycle
oscillator with an active current limit circuit, driver and high current output switch. This series was specifically
designed to be incorporated in Step-Down and Step-Up and Voltage-Inverting applications with a minimum number
of external components.
FEATURES
FUNCTIONAL BLOCK DIAGRAM
Operation from 3.0 V to 40 V Input
Low Standby Current
Current Limiting
Output Switch Current to 1.5 A
Output Voltage Adjustable
Frequency Operation to 100 kHz
Precision 2% Reference
MAXIMUM RATINGS
Rating Symbol
Value
Unit
Power Supply Voltage
V
CC
40
Vdc
Comparator Input Voltage Range
V
IR
-0.3
to
+40
Vdc
Switch Collector Voltage
V
C(switch)
40 Vdc
Switch Emitter Voltage (Vpin 1 = 40 V)
V
E(switch)
40 Vdc
Switch Collector to Emitter Voltage
V
CE(switch)
40
Vdc
Driver Collector Voltage
I
C(driver)
40 Vdc
Driver Collector Current (Note 1)
I
C(driver)
100 mA
Switch Current
I
SW
1.5
A
Power Dissipation and Thermal Characteristics
Ceramic Package, U Suffix T
A
= +25C
Thermal Resistance
Plastic Package, P Suffix T
A
= +25C
Thermal Resistance
SOIC Package, D Suffix
TA
= +25C
Thermal Resistance
P
D
R
JA
P
D
R
JA
P
D
R
JA
1.25
100
1.25
100
625
160
W
C/W
W
C/W
mW
C/W
Operating Junction Temperature
TJ
+150
C
Operating Ambient Temperature Range
T
A
0 to +70
C
Storage Temperature Range
Tstg
-65to+150 C
IL34063A
2
ORDERING INFORMATION
Device Temperature
Range
Package
IL34063A
D
0 to +70C
SO-8
IL34063A
P1
Plastic
DIP
ELECTRICAL CHARACTERICISTICS
(V
CC
= 5.0 V, T
A
= 0 to +70
o
C unless otherwise specified.)
Characteristics Symbol
Min
Typ
Max
Unit
OSCILLATOR
Frequency (V
Pin 5
= 0 V, C
T
= 1.0 nF, T
A
= 25C)
fosc
24
33
42
kHz
Charge Current (V
CC
= 5.0 V to 40 V, T
A
= 25C)
Ichg
24
33
42
A
Discharge Current (
V
CC
= 5.0 V to 40 V, T
A
= 25C)
Idischg
140
200
260
A
Discharge to Charge Current Ratio (Pin7 to Vcc, T
A
=25C)
Idischg/Ichg 5.2 6.2 7.5 --
Current Limit Sense Voltage (Ichg = Idischg, T
A
= 25C)
Vlpk(sense) 250 300 350 mV
OUTPUT SWITCH (Note 3)
Saturation Voltage, Darlington Connection (I
SW
= 1.0 A, Pins
1, 8 connected)
V
CE
(sat) -- 1.0 1.3 V
Saturation Voltage (I
SW
= 1.0 A, R
Pin 8
= 82
to V
CC
.
Forced
= 20)
V
CE
(sat) -- 0.45 0.7 V
DC Current Gain (I
SW
= 1.0 A, V
CE
=
5.0 V, T
A
= 25C) h
FE
50
120
--
--
Collector Off-State Current (V
CE
= 40V)
I
C
(off) -- 0.01
100
A
COMPARATOR
Threshold Voltage (T
A
= 25C)
(T
A
= T
LOW
to T
HIGH
)
Vth 1.225
1.21
1.25
--
1.275
1.29
V
Threshold Voltage Line Regulation (V
CC
= 3 0 V to 40 V)
Regime
1.4 5.0 mV
Input Bias Current (Vin=0V)
I
IB
--
-40
-400
nA
TOTAL DEVICE
Supply Current (V
CC
= 5 0 V to 40 V, C
T
= 1 0 nF, V
pin7
=
V
CC
.
V
Pin5
> Vth, Pin 2 = Gnd, Remaining pins open)
I
CC
2.5 4.0 mA
NOTES:
1. Maximum package power dissipation limits must be observed.
2.
Low duty cycle pulse techniques are used during test to maintain Junction temperature as close to ambient
temperature as possible
3.
If the output switch is driven into hard saturation (non Darlington configuration) at low switch currents (< 300 mA) and
high driver
currents (>30 mA), it may take up to 2.0
s to come out of saturation This condition will shorten the off' time at
frequencies > 30 kHz,
and is magnified at high temperatures This condition does not occur with a Darlington configuration,
since the output switch cannot
saturate If a non Darlington configuration is used, the following output drive condition is
recommended
Forced
of output switch = I
C
,
output/(Ic, driver -7.0 mA*) > 10
*The 100
. resistor in the emitter of the driver device requires about 7.0 mA before the output switch conducts
Pin connection
PDF 
ZIP