TGS MC34063A Dc-to-dc converter control circuit Datasheet

TIGER ELECTRONIC CO.,LTD
DC-to-DC Converter Control Circuits
MC34063A
Outline Drawing
GENERAL DESCRIPTION
The MC34063A is a monolithic control
circuit co ntaining th e primary functions
required for DC-to-D C converters. These
devices consist of an internal temperature
co mpensated
reference,
comparator,
controlled duty cycle oscillator with an
active current li mit circuit, driver and high
DIP8
current output switch. This series was specifically designed to be incorporated in
Step-Down and Step-Up and voltage- Inver ting applications with a mini mu m nu mb er
of external co mponents.
FEATURES
z
Operation fro m 3.0V to 40V Input
z
Low Standby Current
z
Current Limiting
z
Output Switch Current to 1.2A
z
Output Voltage Adjustable
z
Frequency Operation to 100kHz
z
Precision 2% Reference
SOP8
1/9
MC34063A
BLOCK DIAGRAM
PIN CONNECTION
Switch
ollector
Switch
Emitter
1
2
MC34063A
8
Drive
Collector
7
Ipk
Timing
apacitor
3
6
Vcc
Ground
4
5
Comparator
Inverting
Input
MAXIMUM RATINGS (Ta=25°C)
Rating
Symbol
Value
Unit
Power Supply Vo ltage
Vcc
40
V
Co mparator Input Voltage Range
VIR
0.3~40
V
Switch Collector Vo ltage
Vc(switch)
40
V
Switch Emitter Voltage (V P in 1 =40V)
V E (switch)
40
V
Switch Collector to Emitter Vo ltage
V C E (switch)
40
V
Driver Collector Vo ltage
Vc(drive)
40
V
Driver Collector Cu rrent (Note 1)
Ic(drive)
100
mA
ISW
1.2
A
1.25
W
625
mW
Ta
0~70
°C
Tstg
-65~150
°C
Switch Current
Power Diss ipation
DIP8
SOP8
Operating Ambient Temp erature Range
Storage Temperature Range
PD
Notes: 1.Maximum package power dissipation limits must be observed
2.ESD data available upon request
2/9
MC34063A
ELECTRICAL CHARACTERISTICS
(Unless otherwise specified: Vcc=5.0V, Ta=0~70°C)
CHARACT ERISTICS
SYMBOL
MIN
TYP MAX UNIT
Frequency (Vpin5=0V, Vcc=5.0V)
fosc
24
33
42
kHz
Charge current (Vcc=5.0~40V, Vpin3=L)
Ichg
24
31
42
µA
199
260
µA
6.2
7.5
300
350
mV
0.9
1.3
V
0.45
0.7
V
100
µA
1.23 1.25
4.0
1.27
5.0
V
mV
IIB
-40
-400
nA
Icc
2.36
4.0
mA
OSCILLATOR
Discharge current (Vcc=5.0~40V, Vpin3=H)
Idischg
140
Discharg e to charge current ratio
Idischg/Ichg 5.2
(V P I N 7 =V C C , Ta=25°C)
Current li mit sense voltage
Vipk(sense) 250
(Ichg=Idischg, Ta=25°C)
OUTPUT S WITCH (N ote 3)
Saturation voltage, Darlington connection(Note 4)
V C E (sat)
(I S W =0.8A, pins 1,8 connected)
Saturation voltage, Darlington connection
V C E (sat)
(I S W =0.8A, Rpin 8=82Ω to Vcc)
DC current gain (I S W =0.8A,V C E =5.0V, Ta=25°C)
hFE
50
Collector off-state current (V C E = 40V)
Ic(off)
COMPAR ATOR
Threshold voltage (Ta=25°C, Vcc=5.0V)
Threshold voltage line regulation (Vcc=5.0~40V)
Vth
Regline
Input bias cu rrent(Vin=0V)
120
2
TOTAL DEVICE
S u p p l y c u r r e n t ( V c c = 5 . 0 ~ 4 0 V, V p i n 5 = H )
Notes: 3. Low duty cycle pulse techniques are used during test to maintain junction temperature
as close to ambient temperature as possible.
4. 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 for it 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 βof output switch : Ic output/ (Ic drive –7.0mA)* ≥10
*The 100Ω resistor in the emitter of the driver device requires about 7.0 mA before the output
switch conducts.
3/9
MC34063A
APPLICATION CIRCUITS
1.Step-Up Converter
test
conditions
Results
Line Regulation
Vin=8.0~16V, Io=175mA
30mV=±0.05%
Load Regu lation
Vin=12V,Io=75~175 mA
10mV=±0.017%
Output Ripp le
Vin=12V, Io=175 mA
400mVpp
Efficiency
Vin=12V, Io=175mA
87.7%
Output Ripple With Optional Filter
Vin=12V, Io=175mA
40mVpp
2.External Current Boost Connections for Ic Peak Greater than 1.5A
(1).External NPN Switch
(2 ) External NPN Saturated Switch (Note 4)
4/9
MC34063A
3.Step-Down Converter
test
conditions
Results
Line Regulation
Vin=15~25V, Io=500mA
12mV=±0.12%
Load Regulation
Vin=25V,Io=50~500 mA
3.0mV=±0.03%
Vin=25V, Io=500 mA
120mVpp
Vin=25V,RL=0.1Ω
1.1A
Efficiency
Vin=25V, Io=500mA
83.7%
Output Ripple With Optional Filter
Vin=25V, Io=500mA
40mVpp
Output Ripp le
Short Circuit Current
4.External Current Boost Connections for Ic Peak Greater than 1.5A
(1).External NPN Switch
(2) External NPN Saturated Switch
5/9
MC34063A
5.
Voltage inverting converter
test
conditions
Results
Line Regulation
Vin=4.5~6.0V, Io=100mA
3.0mV=±0.012%
Load Regulation
Vin=5.0V,Io=10~100mA
3.0mV=±0.09%
Vin=5.0V, Io=100 mA
500mVpp
Vin=5.0V,RL=0.1Ω
910mA
Efficiency
Vin=5.0V, Io=100mA
62.2%
Output Ripple With Optional Filter
Vin=5.0V, Io=100mA
70mVpp
Output Ripp le
Short Circuit Current
6.External Current Boost Connections for Ic Peak Greater than 1.5A
(1).External NPN Switch
(2) External NPN Saturated Switch
6/9
MC34063A
CHARACTERISTICS CURVES
Output switch on-off time versus
Timing capacitor waveform
oscillator ti ming capacitor
Emitter fo llower configuration output
common emitter co nfiguration output
Saturation voltage versus emitter
switch saturation voltage versus
current
co llector current
current limit sense voltage versus
standby supply current versus
temperature
supply voltage
7/9
MC34063A
MARKING INFORMATION:
OUTLINE DRAWING
DIP8:
Unit:mm
8/9
MC34063A
SOP8:
Unit:mm
9/9
Similar pages