DC-DC Converter Control Circuits
otherwise specified, see note 2)
MC34063A
ELECTRICAL CHARACTERISTICS
(Refer to the test circuits, V
CC
=5V, T
a
=T
LOW
to T
HIGH
, unless
OSCILLATOR
SYMBOL
PARAMETER
F
OSC
Frequency
I
chg
Charge Current
I
dischg
Discharge Current
I
dischg
/I
chg
Discharge to Charge Current Ratio
V
ipk(sense)
Current Limit Sense Voltage
TEST CONDITIONS
V
pin5
= 0 V ,C
T
= 1nF ,T
a
= 25
o
C
V
CC
= 5 to 40V ,T
a
= 25
o
C
V
CC
= 5 to 40V ,T
a
= 25
o
C
Pin 7= V
CC
,T
a
= 25
o
C
I
chg
= I
dischg
,T
a
= 25
o
C
MIN.
24
24
140
5.2
250
TYP.
33
35
220
6.5
300
MAX. UNIT
42 KHz
42
260
7.5
350
㎷
㎂
㎂
OUTPUT SWITCH
SYMBOL
PARAMETER
V
CE(sat)
Saturation Voltage,
Darlington connection
V
CE(sat)
h
FE
I
C(off)
Saturation Voltage
DC Current Gain
Collector Off-State Current
I
SW
= 1A ,R
pin8
= 82Ω to V
CC
,
Forced
β
~ 20
I
SW
= 1A, V
CE
= 5V, T
a
= 25
o
C
V
CE
= 40V
50
75
0.01
100
㎂
0.45
0.7
V
TEST CONDITIONS
I
SW
= 1A ,Pins 1,8 connected
MIN.
TYP.
1.0
MAX. UNIT
1.3
V
COMPARATOR
SYMBOL
PARAMETER
V
th
Threshold Voltage
Reg
line
I
IB
Threshold Voltage Line Regulation
Input Bias Current
TEST CONDITIONS
T
a
= 25
o
C
T
a
= T
LOW
to T
HIGH
V
CC
= 3 to 40V
V
IN
= 0V
MIN.
1.225
1.21
TYP.
1.25
1
-5
MAX. UNIT
1.275 V
1.29
V
5
㎷
-400
㎁
TOTAL DEVICE
SYMBOL
PARAMETER
I
CC
Supply Current
TEST CONDITIONS
V
CC
= 5 to 40V, C
T
=1㎋
Pin7= V
CC
,V
pin5
>V
th
, Pin2=GND
Remaining pins open
for MC34063A
MIN.
TYP.
1.4
MAX. UNIT
4
㎃
Notes:
1) Maximum package power dissipation limit must be observed.
2) T
LOW
= '-30℃, T
HIGH
= '+125℃
3) If Darlington configuration is not used, care must be taken to avoid deep saturation of output switch.
The resulting switch-off time may be adversely affected.
In a Darlington configuration the following output driver condition is suggested:
Forced
β
of output current switch=
COUTPUT
/(I
CDRIVER
-1㎃
*
)≥10
I
*
Current less due to a built in 1K antileakage resistor.
Ω
May. 2009 - Rev. 1.2
HTC
−
3
−
HTC [ HTC KOREA TAEJIN TECHNOLOGY CO. ]
