TECHNICAL DATA Automotive Wash Wiper Timer The SL33197A 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 SL33197A requires very few external components for full system implementation. The intermittent control pin can be switched to ground or Vbat to meet a large variety of possible applications. The intermittent timing can be fixed or adjustable via an external resistor. The SL33197A is built using bipolar technology and parametrically specified over the automotive ambient temperature range and 8.0 to 16 V supply voltage. The SL33197A 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 SLS SL33197A ORDERING INFORMATION SL33197AN DIP SL33197AN-01 DIP SL33197AD SOIC SL33197AD-01 SOIC TA = -45° to 105°C (SOIC) TA = -45° to 125°C (DIP) System Logic Semiconductor 1 SL33197A Representative Block Diagram This device contains 390 active transistors. ELECTRICAL CHARACTERISTICS (–45°C ≤ TA ≤ +125°C, 8.0 V ≤ VCC ≤ 16 V, unless otherwise noted. Typical values reflect approximate mean at TA = 25°C with VCC = 14 V at the time of initial device characterization.) Characteristic Functional Supply Voltage Range Operating Supply Voltage Range Standby Supply Current (VCC = 16 V, R2 = 68 k) Standby Current INT Active (R3 = 2.5 k) Standby Current Relay “On” (R2 = 68 k) Standby Current INT and Relay “On” (R2 = 68 k, R3 = 2.5 k) Oscillator Variations with Supply Voltage and Temperature ( excluding external component tolerances, C2 = 100nF polyester capacitor) (Notes 1 & 2) 10V ≤ Vbb ≤ 16V 8.0V ≤ Vbb ≤ 16V Relay Resistance Output Voltage ( Iout = 200 mA ) Output Clamp Voltage ( Iout = 20 mA ) (for SL33197AN/D) (for SL33197AN/D-01) Oscillator Period Coefficient (TA= 25 °C) Vbb = 13V ( Note 3) Vbb = 13V ( INT Connected to Gnd) (Note 4) Vbb = 13V ( INT Connected to Vbat, R1 = 220 Ω)(Note 4) CONT Threshold( VCC = 13V) CONT Threshold( VCC = 16V) Symbol VCCF VCCOP ICC ICC ICC ICC KOSC RL Vout Vcl tb1 tb2g t b2v Vih Vih Min 8.0 8.0 - Typ 4.0 7.0 7.5 10.0 Max 18 16 5.2 8.4 11.2 14.5 60 19.5 27 10 15 0.9 - 1.5 22 32 0.98 15.1 11.5 6.0 - 1.0 15.5 12.1 VCC/2 1.03 15.9 12.7 8.5 - Unit V V mA mA mA mA % Ω V V V - V V NOTES: 1. The oscillator frequency is defined by the current flowing through 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, any extra current through the resistor R1 other than the current used by the device will cause timing deviations in tb2 timings (as in the case where two devices are sharing a common R1 resistor). 2. The oscillator stability with temperature is dependent on the temperature coefficients of the external components. If the capacitance value of the external capacitor varies more than 5% over the parametric temperature range, the figures quoted for oscillator variation are not valid. 3. The tb1 duration is given by coefficient 4 x R2 x C2 (tb1 duration = tb1 x 4 x R2 x C2). 4. The tb2 duration is given by coefficient x R3 x C2 (tb2 duration = tb2 x R3 x C2). SLS System Logic Semiconductor 2 SL33197A SL33197A Figure 1. Intermittent Wash Wiper Typical Application This application shows the SL33197A with the external wirings and two speed wiper motor. This application has the Intermittent and Wash Wiper functions. INTRODUCTION The SL33197A 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 SL33197A is designed to directly drive a wiper motor relay. The SL33197A is suitable for both front and rear wiper applications. The SL33197A connects directly to the vehicle’s battery voltage (Vbat) through a 220Ω resistor used with a 47 µF de–coupling filter capacitor. The device has an internal oscillator controlled by one of two external resistors (R2 and R3) in addition to one external capacitor (C2), dependent on the application function required. The values of C2 and R2 determine the tb1 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 device 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 SL33197A turns the wiper 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 SL33197A also has a continuous function, which 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 the 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 Vbb or to ground. In this configuration, the circuit will respond to the switching of INT to either Vbb 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 tb1 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 or ground for a time duration greater than T1. If INT is disconnected during the time T3; the output will remain on for the remainder of T3. This is illustrated in the diagram on Figure 2. SLS System Logic Semiconductor 3 SL33197A Wash Wipe Operation Conditions: ●INT disconnected. ●CONT disconnected or connected to ground. In this condition, the circuit will respond to the switching of W/W to Vbb after a time T1 (see T1 Debounce Timing). If W/W is disconnected or connected to ground before the end of T1; no action will be taken. After a time T1; the circuit will perform as shown on Figure 3. The output will turn on and remain on for the duration of W/W. When W/W becomes inactive, the output will remain on for T2 = 96 x 4 x tb1. Continuous Operation In this condition, the circuit responds to the switching of CONT to Vbb. If CONT is connected to Vbb, the output will turn on regardless of the state of any other input and remain on so long as CONT is active. This command operates directly on the relay output and does not interfere with any other timing. Therefore, the circuit will not be reset to a defined state. Wash Wiper and Intermittent Operation If W/W is activated during the time INT is also activated, the circuit will respond to W/W after a time T1 (see T1 Debounce Timing). The output will turn on after T1, and stay on for a time T2 + T3 after W/W is deactivated. Following this, normal operation of INT will occur. This is shown on Figure 4. SLS System Logic Semiconductor 4 SL33197A Figure 4. Switching Waveform W/W and INT Active T1 Debounce Timing The criteria for an input signal to be detected is that it should be active at two successive negative internal clock edges. The inputs are sampled on the negative edge of the internal clock. If two consecutive samples are the same, the input is detected as being in that state. Hence the time T1 from a signal becoming active to the time that the circuit responds can be anytime from 4 x tb1 to 2 x 4 x tb1 (due to synchronizing the input to the oscillator period) when the oscillator is oscillating with a time base of tb1 and 4 x tb2 to 2 x 4 x tb2, when the oscillator is oscillating with a time base of tb2. The following table summarizes all T1 debounce timings: Condition INT Active INT Inactive W/W Active When INT Inactive W/W Active When INT Active During T3 W/W Active When INT Active During T4 Debounce Time 4 x tb1 to 2 x 4 x tb1 4 x tb1 to 2 x 4 x tb1 4 x tb1 to 2 x 4 x tb1 4 x tb1 to 2 x 4 x tb1 4 x tb1 to 2 x 4 x tb2 Two SL33197A 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 Application, all of the foregoing operational cases require: R1 ≥1 00 Ω, C1≥4 7 µF R3≥1 .0 kΩ, R4≥4 .7 kΩ, R5≥4 .7 kΩ The circuit will not operate during the transient conditions. 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. SLS System Logic Semiconductor 5 SL33197A Recommended External Component Values Below are the recommended component values to ensure the device will operate properly, and that all specified parameters will stay within their tolerances. R1 should be greater than 100Ω; recommended value of 220Ω. R1 can be up to 500Ω, but in this case the tb2v parameter could be out of it’s specified value (see Electrical Characteristics and Note 1). Also, the minimum operating voltage range should be greater than 8.0 V. The following values should be adhered to: 10 k≤R2 ≤68 kΩ 1.5 kΩ ≤ R3 ≤47 kΩ R4 ≥4 .7 kΩ R5 ≥4.7 kΩ C1≥ 4 7 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 × 4 × R2 × C2 = 1 × 4 × 27e3 × 100e–9 = 10.8 ms tb2 duration_g (INT to Gnd) = tb2g × R3 × C2 = 15.5 × 2.2e3× 100e–9 = 3.41 ms tb2 duration_v (INT to Vbb) = tb2v × R3 × C2 = 12.1 × 2.2e3× 100e–9 = 2.66 ms Intermittent timing calculation: T3 = 16 × 4 × tb1 duration = 16 × 4 × 10.8 ms = 691 ms T4 = 144 × 4 × tb2 duration_g = 144 × 4 × 3.41 ms = 1.96 s (INT connected to Gnd) T4 = 144 × 4 × tb2 duration_v = 144 × 4 × 2.66 ms = 1.53 s (INT connected to Vbb) Wash wipe timing calculation: T2 = 96 × 4 × tb1 = 96 × 4 × 10.8 ms = 4.15 s T1 Debounce Time Calculation (see T1 Debounce Timing) When oscillator is oscillating at tb1: T1 minimum = 4 × tb1 = 4 × 10.8 ms = 43.2 ms T1 maximum = 2 × 4 × tb1 = 2 × 4 × 10.8 ms = 86.4 ms When oscillator is oscillating at tb2: T1 minimum (INT connected to Gnd, tb2g) = 4 × tb2 = 4 ×3.41 ms = 13.6 ms T1 maximum (INT connected to Gnd, tb2g) = 2 × 4 × tb2 = 2 × 4 × 3.41 ms = 27.3 ms SLS System Logic Semiconductor 6 SL33197A N SUFFIX PLASTIC DIP (MS – 001BA) A Dimension, mm 5 8 B 1 4 MIN MAX A 8.51 10.16 B 6.1 7.11 5.33 C L F Symbol C D 0.36 0.56 F 1.14 1.78 -T- SEATING PLANE N G M K 0.25 (0.010) M J H D T NOTES: 1. Dimensions “A”, “B” do not include mold flash or protrusions. Maximum mold flash or protrusions 0.25 mm (0.010) per side. G 2.54 H 7.62 J 0° 10° K 2.92 3.81 L 7.62 8.26 M 0.2 0.36 N 0.38 D SUFFIX SOIC (MS - 012AA) Dimension, mm A 8 5 B H 1 G P 4 D K SEATING PLANE J F 0.25 (0.010) M T C M NOTES: 1. Dimensions A and B do not include mold flash or protrusion. 2. Maximum mold flash or protrusion 0.15 mm (0.006) per side for A; for B ‑ 0.25 mm (0.010) per side. SLS MIN MAX A 4.8 5 B 3.8 4 C 1.35 1.75 D 0.33 0.51 F 0.4 1.27 R x 45 C -T- Symbol M G 1.27 H 5.72 J 0° 8° K 0.1 0.25 M 0.19 0.25 P 5.8 6.2 R 0.25 0.5 System Logic Semiconductor 7