IL33197

IL33197 INTEGRAL | Alldatasheet

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AUTOMOTIVE WASH WIPER TIMER The IL33197A is a standard wiper timer control device designed for harsh automotive applications. The device can perform the intermittent, after wash, and continuous wiper timer functions. It is designed to directly drive a wiper motor relay. The IL33197A requ ires very few external components for full system implementation. The intermittent control pin can be switched to ground or V bat to meet a large variety of possible applications. The intermittent timing can be fixed or adjustable via an external resistor. The IL33197A is built using bipolar technology and param etrically specified over the automotive ambient temperature range and 8.0 to 16 V supply voltage. The IL33197A can operate in both front and rear wiper applications. Adjustable Time Interval of Less Than 500 ms to More Than 30 s Intermittent Control Pin Can Be Switched to Ground or Vbat Adjustable After Wipe Time Priority to Continuous Wipe Minimum Number of Timing Components Integrated Relay Driver With Free Wheeling Protection Diode Operating Voltage Range From 8.0 to 16 V For Front Wiper and Rear Wiper Window

Applications

This device contains 60 active transistors. MAXIMUM RATINGS Rating Symbol Value Unit Continuous Supply Voltage (VPin 6) VCC 16 V Storage Temperature T stg –55 to +150 oC Thermal Resistance (Junction–to– Ambient) RθJA 100 oC/W Operating Ambient Temperature Range T A –40 to +125 oC Operating Junction Temperature Range T J –40 to +150 oC Maximum Junction Temperature T J(max) 150 oC Representative Block Diagram

ELECTRICAL CHARACTERISTICS (–40 oC ≤ TA ≤ +125 oC, 8.0 V ≤ VCC ≤ 16 V, unless otherwise noted. Typical values reflect approximate mean at TA = 25 oC with VCC = 14 V at the time of initial device characterization.) Characteristic Symbol Min Typ Max Unit Functional Supply Voltage Range V CCF 8.0 – 18 V Operating Supply Voltage Range V CCOP 8.0 – 16 V Standby Supply Current (VCC = 16 V, R2 = 68 k) I CC – 4.0 5.2 mA Supply Current INT Active (R3 = 2.5 k) I CC – 7.0 8.4 mA Supply Current Relay “On” (R2 = 68 k) I CC – 7.5 11.2 mA Supply Current INT and Relay “On” (R2 = 68 k, R3 = 2.5 k) ICC – 10 14.5 mA Oscillator Variations with Supply Voltage and Temperature (excluding external component tolerances, C2 = 100 nF polyester capacitor) (Notes 1 & 2) K osc %

10 V ≤ Vbb ≤ 16 V – 10 –

8.0 V ≤ Vbb ≤ 16 V – 15 –

Relay Resistance R L 60 – – Ω Output Voltage (Iout = 200 mA) V out – 0.9 1.5 V Output Clamp Voltage (Iout = 20 mA) V cl 19.5 – 22 V Oscillator Period Coefficient (TA = 25 oC) – Vbb = 13 V (Note 3) t b1 0.98 1.0 1.03 Vbb = 13 V (INT Connected to Gnd) (Note 4) t b2g 15.1 15.5 15.9 Vbb = 13 V (INT Connected to Vbat, R1 = 220 Ω) (Note 4) tb2v 11.5 12.1 12.7 CONT Threshold (VCC = 13 V) V ih 6.0 – 8.5 V CONT Threshold (VCC = 16 V) V ih – V CC/2 – V NOTES: 1. The oscillator frequency is defined by the current flowing thr ough the external resistor R2. The voltage at the INT pin is (VCC/2 – Vbe) and hence the current flowing through R3 is different if R3 is connected to Vbb or to Gnd because of the voltage drop across resistor R1. This voltage drop causes the oscillator coefficient for tb2 to be different for the two cases of INT terminated to Gnd or to Vbb. Because of this, the oscillator coefficient is specified with a specific value of R1 whenever INT is connected to Vbb. If R1 is changed, the coefficient will change. Also, an y extra current through the resistor R1 other than the current used by the device will cause timing deviations in t b2 timings (as in the case w here two devices are sharing a common R1 resistor). 2. The oscillator stability with temperature is dependent on t he temperature coefficients of the external components. If the capacitance value of the external capacit or varies more than 5% over the parametric temperature range, the figures quoted for oscillator variation are not valid. 3. The t b1 duration is given by coefficient 4 x R2 x C2 (tb1 duration = tb1 x 4 x R2 x C2). 4. The t b2 duration is given by coefficient x R3 x C2 (tb2 duration = tb2 x R3 x C2).

This application shows the IL33197A with the exte rnal wirings and two speed wiper motor. This application has the Intermittent and Wash Wiper functions. INTRODUCTION The IL33197A is a wiper timer control device designed for use in harsh automotive applications. The device can perform the intermittent, after wash, and continuous wiper timer functions. The IL33197A is designed to directly drive a wiper mo tor relay. The IL33197A is suitable for both front and rear wiper applications. The IL33197A connect s directly to the vehicle’s battery voltage (Vbat) through a 220 Ω resistor used with a 47 µF de–coupling filter capacitor. The device has an internal oscillator controlled by one of two external resistors (R2 a nd R3) in addition to one external capacitor (C2), dependent on the application function required. The values of C2 and R2 determine the t b1 time base. Tb1 is used to generate the relay wiper activation during the INT function (T3) and the after wash timing (T2) during the wash wipe mode. The values C2 and R3 determine the tb2 time base. The tb2 time base is used to generate the pause or intermittent time (T4). The intermittent wiper function can generate intermittent timing (T4) from less than 500 ms to more than 30 seconds. The intermittent function of the dev ice can be activated by the INT input connected to either ground or Vbat. The intermittent timing is externally adjustable by changing the value of resistor R3. The wash wiper timer function detects the water pump motor’s operation. When the pump motor activation is detected, the IL33197A turns the wipe r on for the entire duration of the pump motor’s activation. When the motor is turned off, it generates an after wash timing (T2) to maintain the wiping action. The W/W pin is connected to the water pump motor through a protection resistor (R4). The IL33197A also has a continuous function, wh ich activates the wiper relay whenever the CONT input is activated. The CONT input is connected to a switch through a protection resistor (R5). The CONT input comparator has an input threshold of Vbb/2 with hysteresis. The device has internal debounce circuitry, based on t he oscillator period. This provides filtering of the intermittent (INT) and wash wipe (W/W) input signals (see T1 Debounce Timing paragraph that follows). The device directly drives the wiper motor relay. It internally incorporates a 20 V free wheeling zener diode to protect the device against overvoltage spikes produced when relay is switched off. Intermittent Operation Conditions: W/W not connected or connected to ground. CONT not connected or connected to ground. INT connected to V bb or to ground. In this configuration, the circuit will respond to the switching of INT to either V bb or ground after a time T1 (see T1 Debounce Timing). If INT is disconnected before the end of T1; no action will be taken. After a time T1, the output will be switched on for a duration, T3 = 16 x 4 x t b1 and then switched off for a duration, T4 = 144 x 4 x tb2. This sequence will continue to repeat so long as INT is disconnected from Vbb

The following table summarizes all T1 debounce timings: Condition Debounce Time INT Active 4 x t b1 to 2 x 4 x tb1 INT Inactive 4 x t b1 to 2 x 4 x tb1 W/W Active When INT Inactive 4 x t b1 to 2 x 4 x tb1 W/W Active When INT Active During T3 4 x t b1 to 2 x 4 x tb1 W/W Active When INT Active During T4 4 x t b2 to 2 x 4 x tb2 Two IL33197A Devices Using One Decoupling Resistor and Capacitor Two devices may be connected to the power source using a common R1 resistor for protection against overvoltages. If this is done it should be noted that the current flowing through R1 is increased and hence the voltage drop across R1 is increased. Overvoltage Protection In reference to the Block Diagram and Typical App lication, all of the foregoing operational cases require: R1 ≥ 100 Ω, C1 ≥ 47 µF R3 ≥ 1.0 kΩ, R4 ≥ 4.7 kΩ, R5 ≥ 4.7 kΩ The circuit will not operate during the transient c onditions. By using the above component values, the circuit will be able to sustain the following overvoltages on Vbb without permanent damage: 1. +28 V for 5 minutes 2. –15 V for 5 minutes 3. –16 V cycled off for 1.0 minute 4. +80 V pulse decaying exponentially to 8.0 V in 400 ms repeated 3 times at 1.0 minute intervals. 5. ±300 V pulse decaying exponentially to 30 V in 300 ms with a maximum energy of 1.0 Joule. 6. ±100 V pulse decaying exponentially to 10 V in 2 ms. Recommended External Component Values Below are the recommended component values to ens ure the device will operate properly, and that all specified parameters will stay within their tolerances. R1 should be greater than 100 Ω; recommended value of 220 Ω. R1 can be up to 500 Ω, but in this case the t b2v parameter could be out of it’s specified val ue (see Electrical Characteristics and Note 1). Also, the minimum operating voltage range should be gr eater than 8.0 V. The following values should be adhered to: 10 kΩ ≤ R2 ≤ 68 kΩ; 1.5 kΩ ≤ R3 ≤ 47 kΩ; R4 ≥ 4.7 kΩ; R5 ≥ 4.7 kΩ; C1 ≥ 47 uF; 47 nF ≥ C2 ≥ 470 nF

Application Information

The following is an example of timing calculations using the following external components values: R2 = 22 kΩ, R3 = 2.2 kΩ, C2 = 100 nF (Referring to Block Diagram and Typical Application). Oscillator Time Base Calculation: tb1 duration = tb1 x 4 x R2 x C2 = 1 x 4 x 27e3 x 100e–9 = 10.8 ms; tb2 duration_g (INT to Gnd) = tb2g x R3 x C2 = 15.5 x 2.2e3 x 100e–9 = 3.41 ms tb2 duration_v (INT to Vbb) = tb2v x R3 x C2 = 12.1 x 2.2e3 x 100e–9 = 2.66 ms Intermittent timing calculation: T3 = 16 x 4 x tb1 duration = 16 x 4 x 10.8 ms = 691 ms T4 = 144 x 4 x tb2 duration_g = 144 x 4 x 3.41 ms = 1.96 s (INT connected to Gnd) T4 = 144 x 4 x tb2 duration_v = 144 x 4 x 2.66 ms = 1.53 s (INT connected to Vbb) Wash wipe timing calculation: T2 = 96 x 4 x tb1 = 96 x 4 x 10.8 ms = 4.15 s T1 Debounce Time Calculation (see T1 Debounce Timing) When oscillator is oscillating at tb1: T1 minimum = 4 x tb1 = 4 x 10.8 ms = 43.2 ms T1 maximum = 2 x 4 x tb1 = 2 x 4 x 10.8 ms = 86.4 ms When oscillator is oscillating at tb2: T1 minimum (INT connected to Gnd, tb2g) = 4 x tb2 = 4 x 3.41 ms = 13.6 ms T1 maximum (INT connected to Gnd, tb2g) = 2 x 4 x tb2 = 2 x 4 x 3.41 ms = 27.3 ms