Download KA7500

KA7500
Description
The KA7500 incorporate on a single monolithic chip all the functions required in the construction of a pulse-width-modulation control
circuit. Designed primarily for power supply control ,these devices offer the systems engineer the flexibility to tailor the power
supply control circuitry to hos application. The K A7500 contains an error amplifier , anon-chip adjustable oscillator ,a dead- time
control comparator
,pulse-steering control flip-flop ,a 5-volt, 1% precision regulator , and output-control circuits. The error amplifier
exhibits a common-mode voltage range from -0.3 volts to Vcc -2 volts .The dead time control comparator has a fixed offset that
provides approximately 5% deed time when externally
altered. The on-chip oscillator may be bypassed by terminating RT (pin 6 )
to the reference output and providing a sawtooth input to Ct (pin 5) ,or it may be used to drive the common circuits in
synchronous multiple-rail power supplies . The uncommitted output transistors provide either common circuits in synchronous
Power supplier.The uncommitted output transistors provide either common-emitter or emitter-follower output capability .Each device
provides for push-pull or single-ended output operation, which may be
selected throug h the outpu t - control function . Th
e architecture of these devices prohibits the possibility of either output being pulsed twice during push-pull operation.
Features
• Complete PWM Power Control Circuitry
Uncommitted Outputs for 200 mA sink or Source Current
Output control Selects Singel-Ended or Push-Pull operation
• Internal Circuitry Prohibits Double Pulse at Either output
• Variable Dead-Time Provides Control over Total Range Internal
Regulator Provides a Stable 5-V Reference supply ,1% Circuit
Architecture Allows Easy Synchronization
DIP - 16
Block Digram
Package
BEIJING ESTEK ELECTRONICS CO.,LTD
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KA7500
Absolute Maximum Ratings
Over Operating Free-air Temerature Range (Unless Otherwise
Noted)
Rating
Supply voltage ,Vcc
Amplifier input voltage
Collector output voltage
Collector output current
Operating free-air temperature range
Storage temperature range
Lead temperature 1,6 mm from case for 10 seconds
Value
41
Vcc+0.3
41
250
0 to 70
-65 to 150
260
Unit
V
mA
°C
Recommended Operating Conditions
Parameter
Value
MIN
7
-0.3
Supply voltage ,Vcc
Amplifier input voltage ,Vi
Collector output voltage ,Vo
Collector output current (each transistor)
Current into feedback terminal
Timing capacitor ,CT
Timing resistor ,RT
Oscillator frequency
Operating free-air temperature ,TA
Unit
MAX
40
Vcc-2
40
200
0.3
10
500
200
70
0.0047
1.8
1
0
V
mA
µF
kΩ
kHz
°C
Electrical Characteristics
Over Operating Free-air Temerature Range,Vcc=15V,f=10kHz
Noted)
(Unless Otherwise
Reference Section
Parameter
Output voltage(Vref)
Line regulation
Load regulation
Short-circuit output current***
Test conditions
Io=1mA
Io=1mA,TA=25°C****
Vcc=7V to 40V
Io=1Ma to 10mA
Vref=0
MIN
4.9
4.95
10
Value
TYP**
5
5
2
1
35
Unit
MAX
5.1
5.05
25
15
50
V
mV
mA
BEIJING ESTEK ELECTRONICS CO.,LTD
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KA7500
Oscillator section (See Figure 1)
Parameter
Test conditions*
Frequency
Frequency
Frequency change with temperature *****
Value
TYP**
10
-
MIN
9.2
9.0
CT=0.01µF,RT=12KΩ,TA=25°C
CT=0.01µF,RT=12KΩ
CT=0.01µF,RT=12KΩ
ΔTA=MIN TO MAX
Unit
MAX
10.8
12
2
kHz
Amplifier section (See Figure 2)
Parameter
Test conditions
Value
TYP*
2
25
0.2
MIN
Input offset voltage
Input offset current
Input blas current
Common-mode input voltage range
Open-loop voltage amplification
Unity-gain bandwidth
Vo(pin 3)=2.5V
Vo(pin 3)=2.5V
Vo(pin 3)=2.5V
Vcc=7V to 40V
ΔVo=3V,RL=2KΩ,
-0.3 to Vcc-2
70
Unit
MAX
10
250
1
95
650
mV
nA
µA
V
dB
kHz
Output Section
Parameter
Test conditions
MIN
Collector off-state current
Emitter off-state current
Collector-emitter saturation voltage
Output control input current
Common-emitter
Emitter-follower
VCE=40V,Ccc=40V
Vcc=Vc=40V,VE=0
VE=0,Ic=200mA
VC=15V,IE=-200mA
VI=Vref
Value
TYP**
2
1.1
1.5
Unit
MAX
100
-100
1.3
2.5
3.5
µA
V
mA
Dead -Time Control - Section(See Figure
1)
Parameter
Test conditions
MIN
Input bias current (pin 4)
Maximum duty cycle, each output
Input threshold voltage (pin 4)
P
VI=0 to 5.25V
VI(pin 4)=0,O.C.=Vref
Zero duty cycle
Maximum duty cycle
Value
TYP**
-2
MAX
-10
Unit
3
3.3
Value
TYP**
4
0.7
MAX
4.5
45
µA
%
V
0
M Comparator Section(See Figure 1)
Parameter
Test conditions
MIN
Input threshold voltage(pin 3)
Input sink current (pin 3)
Zero duty cycle
V(pin 3)=0.7V
0.3
Unit
V
mA
BEIJING ESTEK ELECTRONICS CO.,LTD
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KA7500
Total Device
Parameter
Test conditions
MIN
Standby supply current
Pin 6 at Vref
Switching Characteristics, T
Parameter
Vcc=15V
MAX
10
Unit
Value
TYP**
100
25
100
25
MAX
200
100
200
100
mA
25 o C
Test conditions
MIN
Output voltage rise time
Output voltage fall time
Output voltage rise time
Output voltage fall time
Value
TYP**
6
Common-emitter configuration, See figure 3
Emitter-follower configuration. See Figure 4
Unit
ns
*For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
**All typical values except for parameter changes with temperature are at TA=25°C
***Duration of the short-circuit should not exceed one second
****This is guaranteed where the marking code on the package surface is “A”
*****Temperature coefficient of timing capacitor and timing resistor not taken into account.
Parameter Measurement Information
BEIJING ESTEK ELECTRONICS CO.,LTD
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KA7500
Figure 1. Operational test circuit and waveforms
Figure 2.Amplifier characteristics
BEIJING ESTEK ELECTRONICS CO.,LTD
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KA7500
Figure 3. Common - emitter configuration
Figure 4. Emitter - follower configuration
Ordering Information
O RDERI NG NUM BER
R
KA7500
Address :
P ACK AGE
DIP-16
M AR K ING
KA7500
6A06--6A07
Rm 6A07,Changyin Office Building ,No.88,Yong Ding Road,Hai Dian District ,Beijing
Postalcode:100039
Tel: 86-010-58895780 / 81 / 82 / 83 / 84
Fax : 010-58895793
Http://www.estek.com.cn
Email:[email protected]
REV No:01-060816
BEIJING ESTEK ELECTRONICS CO.,LTD
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