PWM Controller. NTE1753 Datasheet

NTE1753 Controller. Datasheet pdf. Equivalent

Part NTE1753
Description Integrated Circuit Pulse Width Modulator (PWM) Controller
Feature NTE1753 Integrated Circuit Pulse Width Modulator (PWM) Control Circuit Description: The NTE1753 is a.
Manufacture NTE
Datasheet
Download NTE1753 Datasheet




NTE1753
NTE1753
Integrated Circuit
Pulse Width Modulator (PWM) Control Circuit
Description:
The NTE1753 is a fixed–frequency pulse width modulation control circuit in a 14–Lead DIP type pack-
age incorporating the primary building blocks required for the control of a switching power supply.
An internal–linear sawtooth oscillator frequency is determined by:
1.1
fOSC ^ RT D CT
Output pulse width modulation is accomplished by comparison of the positive sawtooth waveform
across capacitor CT to either of two control signals. The output is enabled only during that portion
of time when the sawtooth voltage is greater than the control signals. Therefore, an increase in con-
trol–signal amplitude causes a corresponding linear decrease of output pulse width.
The control signals are external inputs that can be fed into the dead–time control, the error amplifier
inputs, or the feed–back input. The dead–time control comparator has an effective 120mV input offset
which limits the minimum output dead time to approximately the first 4% of the sawtooth–cycle time.
This would result in a maximum duty cycle of 96%. Additional dead time may be imposed on the out-
put by setting the dead time–control input to a fixed voltage, ranging between 0 to 3.3V.
The pulse width modulator comparator provides a means for the error amplifiers to adjust the output
pulse width from the maximum percent on–time, established by the dead time control input, down to
zero, as the voltage at the feedback pin varies from 0.5 to 3.5V. Both error amplifiers have a common–
mode input range from –0.3V to (VCC –2V), and may be used to sense power supply output voltage
and current. The error–amplifier outputs are active high and are 0 red together at the non–inverting
input of the pulse–width modulator comparator. With this configuration, the amplifier that demands
minimum output on time, dominates control of the loop.
The NTE1753 has an internal 5.0V reference capable of sourcing up to 10mA of load currents for ex-
ternal bias circuits. The reference has an internal accuracy of ±5% with a typical thermal drift of less
than 50mV over an operating temperature range of 0 to +70°C.
Features:
D Complete Pulse Width Modulation Control Circuitry
D On–Chip Oscillator with Master or Slave Operation
D On–Chip Error Amplifiers
D On–Chip 5.0 Volt Reference
D Adjustable Dead Time Control
D Uncommitted Output Transistor for 200mA Source or Sink



NTE1753
Absolute Maximum Ratings: (TA = 0° to +70°C unless otherwise specified)
Power Supply Voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42V
Collector Output Voltage, VC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42V
Collector Output Current, IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250mA
Amplifier Input Voltage, Vin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VCC +0.3V
Power Dissipation (TA 45°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1000mW
Operating Junction Temperature, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +125°C
Operating Ambient Temperature Range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0° to +70°C
Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55° to +125°C
Thermal Resistance, Junction to Ambient, RΘJA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +80°C/W
Power Derating Factor, 1/RΘJA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.5mW/°C
Derating Ambient Temperature, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +45°C
Recommended Operating Conditions:
Parameter
Power Supply Voltage
Collector Output Voltage
Collector Output Current
Amplifier Input Voltage
Current Into Feedback Terminal
Reference Output Current
Timing Resistor
Timing Capacitor
Oscillator Frequency
Symbol
VCC
VC
IC
Vin
If b
Iref
RT
CT
fOSC
Min
7.0
0.3
1.8
0.0047
1.0
Typ
15
30
47
0.001
25
Max
40
40
200
VCC2
0.3
10
500
10
200
Unit
V
V
mA
V
mA
mA
k
µF
kHz
Electrical Characteristics: (VCC = 15V, CT = 0.01µF, RT = 12k. For typical values TA = +25°C,
for min/max values TA is 0° to +70°C unless otherwise specified.)
Parameter
Symbol
Test Conditions
Min Typ Max Unit
Reference Section
Reference Voltage
Line Regulation
Load Regulation
ShortCircuit Output Current
Output Section
Vref
Regline
Regload
ISC
IO = 1mA
VCC = 7V to 40V
IO = 1mA to 10mA
Vref = 0
4.75 5.0 5.25 V
2 25 mV
3 15 mV
15 35 75 mA
Collector OffState Current
IC(off) VCE = 40V, VCC = 40V
2 100 µA
Emitter OffState Current
IE(off) VCC = VC = 40V, VE = 0
– – –100 µA
CollectorEmitter Saturation Voltage Vsat(C) IC = 200mA, VE = 0, Common Emitter
1.1 1.3 V
Vsat(E) IE = 200mA, VC = 15V, Emitter Follower 1.5 2.5 V
Output Voltage Rise Time
tr TA = +25°C, Common Emitter
100 200 ns
TA = +25°C, Emitter Follower
100 200 ns
Output Voltage Fall Time
tf TA = +25°C, Common Emitter
25 100 ns
TA = +25°C, Emitter Follower
40 100 ns







@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact)