SL34063A
DC-TO-DC CONVERTER CONTROL CIRCUITS
The SL34063A is 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
Power Supply Voltage
Comparator Input Voltage Range
Switch Collector Voltage
Switch Emitter Voltage (Vpin 1 = 40 V)
Switch Collector to Emitter Voltage
Driver Collector Voltage
Driver Collector Current (Note 1)
Switch Current
Power Dissipation and Thermal Characteristics
Ceramic Package, U Suffix T
A
= +25°C
Thermal Resistance
Plastic Package, P Suffix T
A
= +25°C
Thermal Resistance
SOIC Package, D Suffix
TA
= +25°C
Thermal Resistance
Operating Junction Temperature
Operating Ambient Temperature Range
Storage Temperature Range
Symbol
V
CC
V
IR
V
C(switch)
V
E(switch)
V
CE(switch)
I
C(driver)
I
C(driver)
I
SW
P
D
R
θJA
P
D
R
θJA
P
D
R
θJA
TJ
Value
Unit
40
Vdc
-0.3 to +40 Vdc
40
Vdc
40
Vdc
40
Vdc
40
Vdc
100
mA
1.5
A
1.25
100
1.25
100
625
160
+150
0 to +70
-65to+150
W
°C/W
W
°C/W
mW °C/
W
°C
°C
°C
T
A
Tstg
SLS
System Logic
Semiconductor
1
SL34063A
ORDERING INFORMATION
Device
Temperature Range Package
34063AD 0° to +70°C
SO-8
34063AP1
Plastic DIP
Pin connection
ELECTRICAL CHARACTERICISTICS
(V
CC
= 5.0 V, T
A
= 0 to +70
o
C unless otherwise specified.)
Symbol
OSCILLATOR
Frequency (V
Pin 5
= 0 V, C
T
= 1.0 nF, T
A
= 25°C)
fosc
Charge Current (V
CC
= 5.0 V to 40 V, T
A
= 25°C)
Ichg
Discharge Current (
V
CC
= 5.0 V to 40 V, T
A
= 25°C)
Idischg
Discharge to Charge Current Ratio (Pin7 to Vcc, T
A
=25°C)
Idischg/Ichg
Current Limit Sense Voltage (Ichg = Idischg, T
A
= 25°C)
Vlpk(sense)
OUTPUT SWITCH (Note 3)
Saturation Voltage, Darlington Connection (I
SW
= 1.0 A,
V
CE
(sat)
Pins 1, 8 connected)
Characteristics
Min
24
24
140
5.2
250
—
—
50
—
1.225
1.21
1.2375
Typ
33
33
200
6.2
300
1.0
0.45
120
0.01
1.25
—
1.25
1.4
-40
2.5
Max
42
42
260
7.5
350
1.3
0.7
—
100
1.275
1.29
1.2625
5.0
-400
4.0
Unit
kHz
µA
µA
—
mV
V
V
—
µA
V
V
mV
nA
mA
Saturation Voltage (I
SW
= 1.0 A, R
Pin 8
= 82
Ω
to V
CC
.
V
CE
(sat)
Forced
β
= 20)
DC Current Gain (I
SW
= 1.0 A, V
CE =
5.0 V, T
A
= 25°C)
h
FE
Collector Off-State Current (V
CE
= 40V)
I
C
(off)
COMPARATOR
Threshold Voltage (T
A
= 25°C)
Vth
(T
A
= T
LOW
to T
HIGH
)
Threshold Voltage (T
A
= 25°C) **
Threshold Voltage Line Regulation (V
CC
= 3 0 V to 40 V)
Input Bias Current (Vin=0V)
Vth
Regime
I
IB
TOTAL DEVICE
Supply Current (V
CC
= 5 0 V to 40 V, C
T
= 1 0 nF, V
pin7
= V
CC
.
I
CC
V
Pin5
> Vth, Pin 2 = Gnd, Remaining pins open)
—
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
µs
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 Darlingto n configuration,
since the output switch cannot saturate If a non Darlington configuration is used, the following output drive condition is
recommended
Forced
β
of output switch = I
C
, output/(Ic, driver -7.0 mA*) > 10
*The 100
Ω.
resistor in the emitter o f the driver device requires about 7.0 mA before the output switch conducts
**Possible
version for shipment
SLS
System Logic
Semiconductor
2
