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U2350B-FP
PWM Speed Control for Permanent Excited DC Motors
Description
The monolithic integrated bipolar circuit U2350B is a MOSFET or IGBT - control circuit which works on the principle of pulse width modulation (PWM). The overall concept enables the construction of a power controller with mains voltage compensation where intermittent operation is also possible. In addition, the circuit also enables mains-voltage compensated current control, which maintains the power supplied at a constant level after the preset threshold has been exceeded.
Features
D D D D D D D D
Pulse width control up to 30 kHz clock frequency Mains supply compensation Current regulation Temperature monitoring with indicator Active operation indicator Blink-warn indicator Switchable to interval operation Push-pull output stage for separate supply Package: SO16
D Supply voltage monitoring D Temperature compensated supply voltage limitation
Applications
D Domestic equipment D Tools
Block Diagram
2 LED control 1 +VS 16 GND Voltage limitation 12 Push– pull output 15 14 13 8 6 7 Oscillator
4
Temperature monitoring
Output control
PWM Control
10 9
5 Tristate
Program logic
Current limitation
11
95 10873
Figure 1. Block diagram
TELEFUNKEN Semiconductors Rev. A1, 29-May-96
1 (9)
U2350B-FP
2 (9)
R1 VM = 230 V~ 56 k W/ 2W +VS D3 red 2 LED – logic IGBT 14 T1 3 420 mV + – 100% 4 GND 12 Multi Stop Normal Progr.– logic Comparator 2 – + R 11 6 Voltage monitoring Oscillator 1.2 V/ 1.5 V 10 S1 R9 120 k W Impedance converter S3 S2 8 Comparator 1 – + 9 C1 10 nF
95 10868
D2 M
green 1 16 D1 15 Push pull stage BYT86 –800 47 mF/ 350 V C6 Supply voltage limitation
R 12
R10
82 k W
80% Q S 13 R Q R12 10 kW
Output stage logic
C7 + 350 mV – +V S open 5
10 mF/ 35 V
R8 0.22 W/ 4W C2 22 nF R7
Tristate switch
11 R6 180 k W
5.6 M W R3 220 k W
Figure 2. Block diagram with external circuit
C4 7 R5 C5 680 nF
C3
220 nF
120 k W
R13 NTC
220 nF
R14
Speed
R4 7.5 k W
47 k W
100 k W
TELEFUNKEN Semiconductors Rev. A1, 29-May-96
R 15 10 k W
U2350B-FP
Pin Description
LED1 LED2 n.c. NTC Progr. Rosc Cosc Contr. 1 2 3 4 5 6 7 8
95 11409
16 +VS 15 OUT+ 14 OUT 13 OUT– 12 GND 11 IContr. 10 S1 9 VContr.
Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Symbol LED1 LED2 n.c. NTC Progr. Rosc Cosc Contr. VContr. S1 IContr. GND OUT– OUT OUT+ +VS
Function LED output 1 LED output 2 Not connected Monitoring input Tristate programing Resistor for oscillator Capacitor for oscillator Control input Voltage regulation input Switching output, output S1 Current regulation input Ground – supply for output stage Output + supply for output stage Supply voltage
Supply, Pin 16
The internal voltage limiter in the U2350B enables a simple supply from the rectified line voltage. The supply voltage between Pin 16 (+VS) and Pin 12 (ground) is built up via R1 and is smoothed by C7. The typically 5 mA supply current is simultaneously used to operate the two LEDs D2, D3, which can both be bridged internally. The supply current therefore reaches Pin 16 either via LEDs or the internal switches (Vsat ≤ 1.2 V). Series resistor, R1, can be calculated as follows: R 1max
Voltage Monitoring
Whilst the operating voltage is being built up or reduced, uncontrolled output pulses of insufficient amplitude are suppressed by the internal monitoring circuit. The latch is also reset, the LED D2 (operating indicator) between Pin 2 and Pin 16 is switched off and the control input “Pin 8” is connected to ground via switch S3 and a 1 kW resistor. In connection with a switching hysteresis of approximately 2 V, this mode of operation guarantees fail-safe start-up each time the operating voltage is switched on, in the same way as after short mains interruptions. Connecting the control input Pin 8 with a capacitor can therefore make a soft start with rapid recovery possible.
+V
Mmin
– V Smax I tot
+ V –15% V + maximum supply voltage )I I +I I + Max. current consumption of the IC I + Current consumption of the external components
V Mmin
Smax mains tot Smax x Smax x
whereas
Pulse Width Control with Mains Voltage Compensation, Pins 8, 9, 10
Average value of the voltage over the load is controlled to an infinitely selectable value by the comparator Comp. 1 with hysteresis. The rectified mains voltage is divided by R3 and R4 and lead in Pin 10. The capacitor C1 is charged via R9 until the voltage V9, which is present at the inverting input of Comp. 1, is more positive than the control voltage V8 arriving at the non-inverting input via an impedance converter. During the charge time, which is dependent of the mains voltage, the pulse output is at high potential and the switching output Pin 10 is open. If V9 now becomes greater than V10, the output from Comp. 1 switches over the output stage logic via an AND gate. 3 (9)
Here, C6 must be selected in this way that the voltage at C7 (figure 2) is not noticeably affected by the load in any mode of operation. For further information regarding mains power.