View U642B_1148388.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

U642B
Interval- and Wipe/ Wash Wiper Control IC
Description
As a convenience feature of the windshield wiper intermittent and wipe/wash operation are implemented in most of the automobiles. The U642B is the low-cost solution for an accurate timing function control. Wipe/wash mode has priority over interval mode. Interval pause and afterwiping time can be set to fixed values by using resistors in a broad time range. Added value can be provided with an individual, continuous adjustment of the interval pause by a potentiometer which may be built into the stalk. For proper operation it is mandatory to feed the signal of the wiper motor`s park switch into U642B.
Features
D Interval pause: 4 to 20 s D Afterwiping time: 2 to 20 s D Wiper motor's park switch D Wipe/wash mode priority D One external capacitor, determines all time sequences D Relay driver with Z-diode D Interference protection according to VDE 0839 or ISO/TR 7637/1 D Load-dump protected
Block Diagram
VS 8 OUT 7 PARK 6 VRef Park switch comparator WASH 5 VRef Input comparator
Load-dump comparator
VRef
Logic
VRef Interval comparator
Wipe / wash comparator
A
B
C
D
E
F
1 GND
2 INT
3 Ct
4 Rt
94 8950
Figure 1. Block diagram
Rev. A4, 10-Apr-01
1 (7)
U642B
Ordering Information
Extended Type Number U642B U642B-FP Package DIP8 SO8 Remarks
Pin Description
Pin 1 2 3 4 5 6 7 8 Symbol GND INT Ct Rt WASH PARK OUT VS Ground Interval switch Timing capacitor C2 Afterwiping time resistance Wipe/Wash switch Park switch for wiper motor Relay control output Supply voltage KI. 15
Figure 2. Pinning
Function
GND INT Ct Rt
1 2
8 7
VS OUT PARK WASH
U642B
3 4
93 7691
6 5
Circuit Description
Interval Function, Pin 2
By closing the interval switch, S2, to supply voltage, VBatt, the relay is activated. The internal current source (Pin 3) which holds the capacitor C2 in charged state is switched-off. As soon as there is a positive potential at the park switch (S1), the current source F (see figure 1) charges the capacitor C2 very fast. After the wiper operation is finished, S1 is again at ground potential, the relay is in "off" position - interval pause begins - the capacitor C2 is discharged through the current source C, till the voltage at Pin 3 is below the threshold of 2 V. Interval pause can be adjusted between 4 s to 20 s with the help of potentiometer R3. Now the relay switches on and the next interval cycle begins. Opening of switch S2 causes the current source A to discharge C2 immediately and current sources C and F are switched-off. at the capacitor is greater than 6.5 V, the relay is turned on as long as the switch "WIWA" is closed. The after-wipe-time begins after the switch is open whereas the sources D and F are switched off and the source E is activated. Source E discharges the capacitor till the voltage is less than 2.2 V. The relay is off and the wiper-motor is supplied via the park switch until the park position will be reached. The after-wipe-time is determined by the current source E which can be regulated with the external resistor RTime. Afterwards the source A discharges the capacitor. The relay switch off is independent of the park switch S1.
Interval and WIWA Functions
The interval function is interrupted immediately when the wipe/ wash mode is activated. The current source A discharges the capacitor to a value of 2 V, afterwards the normal wash function starts. Interval wiping starts immediately when the after-wipetime is over. The switching delays are slightly shorter, because the capacitor is already charged to a value of 2 V. The wipe/ wash function is not interrupted when interval switch S2 is activated. Interval function begins after the WIWA function is over.
Wipe/Wash (WIWA) Operation, Pin 5
By closing the WIWA-switch, S3, to supply voltage, VBatt, the water pump starts spraying water on the windscreen, the current source A is switched-off which keeps the capacitor C2 in discharged state. Now the capacitor is charged through the current sources D and F, and when after a time interval of approximately 100 ms, the voltage
2 (7)
Rev. A4, 10-Apr-01
U642B
10 kW
R
6
R
5 5
10 kW
Relay
8
7
6
47 mF 10 V
C
U642B
1
1
2 C 2.7 kW R 2
3 22 mF 10 V R 4
4
R
2
1
510 W
Rtime = 130 kW
R S 1 S 2
3
10 kW WIWA
Park switch M
M S 3 31
Wiper motor
Interval switch
15 Water pump
94 8951
Figure 3. Application circuit with interval and wipe/wash operation
Rev. A4, 10-Apr-01
3 (7)
U642B
Absolute Maximum Ratings
Parameters Supply voltage Supply current t = 60 s Terminal 15, Pin 8 Pin 8 Pin 7 t = 2 ms t = 200 ms Relay control output current (DC) t = 200 ms Pulse current (control inputs) t = 200 ms Park switch, S1 Wipe/Wash switch, S3 Interval switch, S2 Tamb = 90C Symbol VBatt I8 I8 I7 I7 I6 I5 I2 Ptot Tstg Tamb Value 28 1.5 150 200 1.2 50 50 50 500 -55 to +125 -40 to +85 Unit V A mA mA A mA
Pin 6 Pin 5 Pin 2
Power dissipation
mW C C
Storage temperature range Ambient temperature range
Thermal Resistance
Parameters Junction ambient DIP8 SO8 Symbol RthJA RthJA Value 120 160 Unit K/W K/W
Electrical Characteristics
VBatt = 12 V, Tamb = 25C, reference point is Pin 8 (see figure 3) unless otherwise specified. Parameters Supply voltage Supply current Z-diode limitation Overvoltage Threshold current Threshold voltage Relay control output Saturation voltage Leakage current Park switch Internal pull-up resistance Switching threshold voltage Protection diode Input Ct Internal resistance Interval input, R2 = 2.7 to 30 kW Protection diode Pin 2 I2 = -10 mA I2 = 30 mA/10 ms V2 -0.8 7.6 V I6 = -10 mA I6 = 10 mA Pin 3 R6 = 10 kW Pin 6 R6 V6 V6 V6 R3 50 -3.3 -0.8 7.6 100 kW V V V W Pin 7 I7 = 100 mA I7 = 200 mA V7 I7 100 -1.0 -1.5 V mA I1 VBatt -50 35 mA V Test Conditions / Pins Pin 8 Symbol VBatt I8 V1 Min. 9 10 7.6 Typ. Max. 16.5 Unit V mA V
4 (7)
Rev. A4, 10-Apr-01
U642B
Electrical Characteristics (continued)
VBatt = 12 V, Tamb = 25C, reference point is Pin 8 (see figure 3) unless otherwise specified. Parameters WASH Input, R5 = 10 kW Switching threshold/Hysteresis Protection diode I5 = -10 mA I5 = 10 mA R3 = 0 kW R3 = 10 kW R4 = 130 kW Pin 5 Test Conditions / Pins Pin 5 V5 V -1.4/-5.4 -0.8 7.6 3.6 10.8 4.75 4 12 100 5.25 5.75 4.4 13.2 V V Symbol Min. Typ. Max. Unit
Switching Characteristics, R4 = 47 kW to 300 kW, I4 = -150 mA Interval time Prewash delay After-wipe-time t2 tdel t5 s ms s
12 10 Interval pause ( s ) 8 6 4 2 0 -40
14005
Rint = 0
16 14
Rint = 5 kW
Interval pause (s ) 100
14009
12 10 8 6 4 2 0
Rint = 10 kW
-20
0
20 40 60 Temperature ( C )
80
0
2
4
6 8 10 12 14 16 18 20 Interval resistor ( kW )
Figure 4. Interval pause = f ( T); Ct = 22 mF
12 10 Afterwiping time ( s ) 8 VBatt = 8 V 6 4 Rtime = 300 kW 2 0 -40
14006
Figure 6. Interval pause = f ( RINT); Ct = 22 mF
12
Rtime = 51 kW Afterwiping time ( s )
10 8 VBatt = 16 V 6 4
Rtime = 51 kW
Rtime = 130 kW
Rtime = 130 kW
Rtime = 300 kW 2 0 -40
-20
0
20 40 60 Temperature ( C )
80
100
14007
-20
0
20 40 60 Temperature ( C )
80
100
Figure 5. Afterwiping time = f ( T); Ct = 22 mF
Figure 7. Afterwiping time = f ( T); Ct = 22 mF
Rev. A4, 10-Apr-01
5 (7)
U642B
Package Information
Package DIP8
Dimensions in mm
9.8 9.5 1.64 1.44 7.77 7.47
4.8 max 6.4 max 0.5 min 0.58 0.48 7.62 8 5 2.54 3.3 0.36 max 9.8 8.2
technical drawings according to DIN specifications 13021
1
4
Package SO8
Dimensions in mm
5.00 4.85 1.4 0.4 1.27 3.81 8 5 0.25 0.10 0.2 3.8 6.15 5.85 5.2 4.8 3.7
technical drawings according to DIN specifications 13034
1
4
6 (7)
Rev. A4, 10-Apr-01
U642B
Ozone Depleting Substances Policy Statement
It is the policy of Atmel Germany GmbH to 1. Meet all present and future national and international statutory requirements. 2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems with respect to their impact on the health and safety of our employees and the public, as well as their impact on the environment. It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as ozone depleting substances (ODSs). The Montreal Protocol (1987) and its London Amendments (1990) intend to severely restrict the use of ODSs and forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban on these substances. Atmel Germany GmbH has been able to use its policy of continuous improvements to eliminate the use of ODSs listed in the following documents. 1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively 2. Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental Protection Agency (EPA) in the USA 3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C (transitional substances) respectively. Atmel Germany GmbH can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain such substances.
We reserve the right to make changes to improve technical design and may do so without further notice. Parameters can vary in different applications. All operating parameters must be validated for each customer application by the customer. Should the buyer use Atmel Wireless & Microcontrollers products for any unintended or unauthorized application, the buyer shall indemnify Atmel Wireless & Microcontrollers against all claims, costs, damages, and expenses, arising out of, directly or indirectly, any claim of personal damage, injury or death associated with such unintended or unauthorized use. Data sheets can also be retrieved from the Internet: http://www.atmel-wm.com
Atmel Germany GmbH, P.O.B. 3535, D-74025 Heilbronn, Germany Telephone: 49 (0)7131 67 2594, Fax number: 49 (0)7131 67 2423
Rev. A4, 10-Apr-01
7 (7)

▲Up To Search▲

Price & Availability of U642B

	To Download U642B Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .