LSI/CSI UL ® LS7634 LS7635 LS7634FO LS7635FO LSI Computer Systems, Inc. 1235 Walt Whitman Road, Melville, NY 11747 (631) 271-0400 FAX (631) 271-0405 A3800 September 2006 TOUCH CONTROL HALOGEN LAMP DIMMER PIN ASSIGNMENT - TOP VIEW 1 MODE 2 TEST SYNC 3 LS7634 LS7635 V DD (+V ) LSI FEATURES: • Touch or pushbutton control of incandescent lamps and transformer-coupled halogen lamps • Works with Magnetic or ElectronicTransformers • Automatic Safety Shutdown • Three operating modes • Extension input for remote activation • 50Hz/60Hz AC line frequency • +5V Power Supply (VDD - VSS) • LS7634, LS7635 (DIP); LS7634-S, LS7635-S (SOIC); LS7634FO, LS7635FO (DIP); LS7634FO-S, LS7635FO-S (SOIC) - See Figure 1 - 4 8 TRIG 7 V SS (-V ) 6 EXT 5 SENS FIGURE 1 INPUT/OUTPUT DESCRIPTION: APPLICATIONS: Electronic dimmers for wall switch control of ceiling mounted lighting, foot switch control of large floor lamps and hand switch control of table lamps. VDD (Pin 1) Supply voltage positive terminal. Vss (Pin 7) Supply voltage negative terminal. BACKGROUND AND GENERAL DESCRIPTION: A typical electronic dimmer may not operate properly with the inductive load encountered when driving a transformer-coupled low-voltage halogen lamp. The inductive load can cause a phenomenon called half-waving, wherein the triac fires in alternate half-cycles only, which may lead to the thermal destruction of the load transformer. The problems encountered in driving an inductive load are addressed by the LS7634/LS7635 family of CMOS ICs as follows: MODE (Pin 2) - See Table 1 All variations of LS7634 and LS7635 can operate in 3 different modes. The 3-state MODE input selects the operating modes: Vss = Mode 0; Float = Mode 1; VDD = Mode 2 1. Delayed triac cut-off. When a trigger pulse is due to occur at a conduction angle which coincides with the on-state of the triac, the trigger pulse is delayed until the triac has turned off. This eliminates the underlying cause of half-waving. SENS (Pin 5) - See Table 1 A Logic 0 applied to this input alters the TRIG output either by turning it on, turning it off or by changing its conduction angle. Specifically which action takes place is dependent on the type of activation of the SENS input, namely SHORT or LONG touch and the prior state of TRIG output. 2. Delayed triac turn-on and safety shutdown With inductive loads, the holding current needed to maintain the triac On-State, may seriously lag behind the gate trigger signal causing the triac to turn off prematurely. If the frequency of occurrences of the delayed turn-on exceeds a preset threshold, a shutdown is initiated by turning off the triac trigger pulses. The safety-shutdown threshold value is accumulated in a 4-bit Up/Down counter. The count increments for every occurrence of delayed turn-on and decrements once every 8 SYNC pulses (AC line cycles). The counter will not decrement below zero. If the count reaches 15, the safety-shut-down is effected. SYNC (Pin 4) - See Figure 6 The AC line frequency is applied to this input. All internal timings are synchronized to the AC. The Load On/Off status information is also derived from this input. EXT (Pin 6) Same functionality as the SENS input, except that a Logic 1 is the active level at this input. EXT input is intended to be operated from a remote site with long cable connection, when noise can be expected. The sampling method used at this input makes it less sensitive to noise. TRIG (Pin 8) The TRIG output is a low level pulse occurring once every halfcycle of the AC and is intended to drive the gate of a triac in series with the load. The conduction angle, ø, of the TRIG pulse can be varied by means of LONG and SHORT touches at either the SENS or the EXT input. Test (Pin 3) For factory use only. 7634/7635-090606-1 The differences among all versions of LS7634 and LS7635 are: LS7634 (LS7634FO) Upon power-up, the TRIG output is Off. (Upon power-up, the TRIG output is On at maximum conduction angle.) When a LONG touch is applied, the dimming direction automatically reverses whenever maximum or minimum conduction angles are reached. LS7635 NOTE: If the User applies a LONG Touch when the TRIG Conduction Angle is within a “few” degrees of Maximum or Minimum, the TRIG Conduction Angle can move to Maximum or Minimum and stop without the User being able to observe a change in brightness. There-fore, the User should be instructed that if no change in brightness is observed in response to a LONG Touch, the LONG Touch should be re moved and reapplied in order to produce a change in brightness. LS7635 (LS7635FO) Upon power-up, the TRIG output is Off. (Upon power-up, the TRIG output is On at maximum conduction angle.) When a LONG touch is applied, the dimming stops whenever maximum or minimum conduction angles are reached. In order to change dimming levels from maximum or minimum, LONG touch must be removed and reapplied.The purpose of this feature is to allow the user to positively locate maximum and minimum conduction angles. TABLE 1 MODE SHORT TOUCH PRE-TOUCH Ø 0 Note 1: Note 2: Note 3: Note 4: Note 5: POST-TOUCH Ø PRE-TOUCH Ø POST-TOUCH Ø DIMMING REVERSAL (Note 5) OFF ON MAX(Note 1) OFF OFF/MIN MAX INTERMEDIATE Varies up from MIN Varies down from MAX Varies from INTERMEDIATE N/A N/A NO OFF ON MEMORY (Notes 2, 3) OFF OFF MIN MAX INTERMEDIATE Varies from memory (Notes 2, 3,4) Varies up from MIN Varies down from MAX Varies from INTERMEDIATE YES N/A N/A YES OFF ON MAX (Note 1) OFF OFF/MIN MAX INTERMEDIATE Varies up from MIN Varies down from MAX Varies from INTERMEDIATE N/A N/A YES 1 2 LONG TOUCH A soft turn-on is produced by slewing up the conduction angle, ø, from minimum at the rate of 1.4˚/8.33ms (60Hz). A soft turn-on is produced by slewing up ø, from minimum to memory. Upon power-up the memory value is defaulted to maximum conduction angle. “Memory” refers to the conduction angle, ø, which existed prior to the current off-state. A soft turn-on is produced by slewing up ø from minimum to memory upon which the dimming is started. NO = Dimming direction does not reverse from prior dimming direction. YES = Dimming direction does reverse from prior dimming direction. N/A = Does not apply. ABSOLUTE MAXIMUM RATINGS: PARAMETER DC supply voltage Any input voltage Operating temperature Storage temperature SYMBOL VDD - Vss VIN TA TSTG VALUE +7 Vss - 0.3 to VDD + 0.3 0 to +90 -65 to +150 UNIT V V °C °C DC ELECTRICAL CHARACTERISTICS: (TA = +25˚C, all voltages referenced to Vss. VDD = +5V unless otherwise noted.) PARAMETER SYMBOL MIN TYP MAX UNIT Supply voltage Supply current VDD IDD 4.5 - 5.0 300 5.5 400 V µA SYNC Lo VISL - - 2.1 V SYNC Hi VISH 2.9 - - V - EXT, SENS Lo VIEL - - 1.5 V - EXT, SENS Hi TRIG Lo TRIG Hi VIEH VOL VOH 3.5 - 0.2 5.0 - V V V - TRIG Sink Current ITSNK 35 - - 7634/7635-010906-2 mA CONDITION Output unloaded VDD = 5.5V - VOTRIG = 2.5V TIMING CHARACTERISTICS (See Figures 2, 3 and 4): PARAMETER SYMBOL MIN TYP fs TSI TSI TS2 TS2 Tw Tw ø ∆ø 40 42 50 342 410 50 - 130 156 1.4 70 333 400 infinite infinite 154 - Hz ms ms ms ms µs µs deg deg 60Hz 50Hz 60Hz 50Hz 60Hz 50Hz - 1.4 1.4 1.4 1.4 1.4 1.4 500 600 - deg/8.33ms deg/10ms deg/33.3ms deg/40ms deg/66.7ms deg/80ms ms ms 60Hz 50Hz 60Hz 50Hz 60Hz 50Hz 60Hz 50Hz SYNC Frequency SHORT Touch LONG Touch TRIG pulse width (see Note 5) Conduction Angle ø incremental steps (Note 1) Soft-on slew rate SS SS SAA SAA SBA SBA TBD TBD A0 to A1/A2 to A0 slew rate (Note 2) A1 to B1/B2 to A2 slew rate (Note 3) B1 to B2 delay (Note 4) - MAX UNI T CONDITION Note 1: Note 2: Note 3: Note 4: Total number of steps = 77. Number of steps from A0 to A1, or A2 to A0 = 55. Number of steps from A1 to B1 or B2 to A2 = 21. ø is at minimum between B1 and B2. TBD is applicable for LS7634 only. For LS7635 when minimum ø is reached, dimming direction reverses only if the LONG Touch is terminated and reapplied. Note 5: TW = 488us (60Hz), 586us (50Hz) available. Contact factory for details. FIGURE 2. TRIG OUTPUT CONDUCTION ANGLE, Ø The information included herein is believed to be accurate and reliable. However, LSI Computer Systems, Inc. assumes no responsibilities for inaccuracies, nor for any infringements of patent rights of others which may result from its use. SYNC ø TRIG TW FIGURE 3. LS7634 TRIG, Ø vs TOUCH (SENS OR EXT) TS1 TS2 SENS SHORT SHORT LONG SHORT LONG SHORT A0 150º Ø MODE Ø 50º OFF SLOPE = SBA 342ms 100º A2 SLOPES = S AA B2 A1 SLOPE = Ss A2 B1 B2 MEMORY A0 A0 150º Ø MODE 1 100º 50º A1 OFF B1 B2 REVERSE A2 A0 150º Ø MODE 2 100º 50º OFF 7634/7635-071406-3 B2 A2 A1 A2 B1 B2 REVERSE LONG FIGURE 4. LS7635 TRIG, Ø vs TOUCH (SENS OR EXT) TS1 TS2 SENS SHORT Ø LONG LONG LONG 342ms 150º 100º MODE Ø LONG SHORT 50º SHORT SLOPE = S BA A2 B2 LONG A0 A0 OFF SHORT A1 SLOPE = S AA B1 B2 A2 B2 A2 SLOPE = S S MEMORY Ø 150º 100º MODE 1 MEMORY REVERSE 50º A1 A2 B1 B2 OFF A2 A1 B1 B2 A0 A0 REVERSE Ø 150º 100º MODE 2 A0 A0 50º A2 B2 OFF B2 FIGURE 5. A Typical Halogen Lamp Dimmer Wall Switch P A2 P SEE NOTE 2 MT1 MT2 R7 R3 + C4 T **R9 C5 R8 G **C6 R5 - Z TOUCH PLATE NOTES SEE NOTE 3 R6 L 115VAC OR 220VAC D1 8 C1 C2 7 TRIG 6 V SS EXT 5 SENS LS7634 / LS7635 R1 V DD 1 R2 MODE TEST SYNC 2 3 4 R4 SEE NOTE 4 C3 LAMP N C1 = 0.15µF, 200V * C1 = 0.15µF, 400V C2 = 0.22µF, 200V * C2 = 0.15µF, 400V C3 = 0.002µF, 10V *Component change for 220VAC **Snubber Network (See Note 5) FIGURE 6. C4 = 100µF, 10V C5 = 0.1µF, 10V R1 = 270Ω, 1/2W * R1 = 1kΩ, 1W R2 = 680kΩ, 1/4W * R2 = 1.5MΩ, 1/4W R3 = 1.5MΩ, 1/4W ELECTRONIC EXTENSION MPS8599 EXT IN914 *R *R 10kΩ TOUCH PLATE 200kΩ *R = 2M Ω for 115VAC *R = 3.6M Ω for 220VAC All Resistors 1/4W P EXTENSIONS: All switching and dimming functions can be implemented by utilizing the EXT input. Use a pushbutton or the electronic switch in conjunction with a Touch Plate as shown in Figure 6. When the plate is touched, a logic high level is generated at the EXT input of the IC for both halfcycles of the line frequency. (See Figure 5) 7634/7635-090606-4 ELECTRONIC EXTENSION (FIG. 7) EXTN * 1. All circuits connected by broken lines are optional. 2. C5 is used only with electronic extension and R7 is used only with mechanical switch. 3. Connection between Pin 6 & Pin 7 should be broken when EXT is used. 4. Magnetic transformer should have thermal protection. 5. Some electronic transformers may require larger values of C2, sensitive gate triacs and snubber networks. C2 values may have to be adjusted to be as high as 0.47uF for 115VAC and 0.33uF for 220VAC. The sensitive gate triacs are chosen for their low holding current. Typical triacs are L4004L6 and L6004L6 for 115VAC and 220VAC applications, respectively. **C6-R9 is the snubber network: C6 = 0.1uF, 200V, R9 = 1k Ohm, 1/2W (115VAC); C6 = 0.05uF, 400V, R9 = 1k Ohm, 1W (220VAC) R4 = 1MΩ to 5MΩ, 1/4W (Select for Sensitivity) R5, R6 = 2.7MΩ, 1/4W R5, R6 = 4.7MΩ, 1/4W R7 = 150kΩ, 1/4W R8 = 62Ω, 1/4W D1 = 1N4148 Z = 5.6V, 1W (Zener) T = Q4004L4 Typical Triac (1) * T = Q5003L4 Typical Triac (1) L = 100µH (RFI Filter) * L = 200µH (RFI Filter) (1) For loads greater than 6A, use an alternistor . APPLICATION EXAMPLE: A typical implementation of the light dimmer circuit is shown in Fig. 5. Here the brightness of the lamp is set by touching the touch plate. The function of different components are as follows: • The 5V DC supply for the chip is provided by Z, D1, R1, C2 and C4. • R2 and C3 generate the filtered signal for the SYNC input AC phase synchronization. • R3 and C5 act as a filter circuit for the electronic extension. If extensions are not used, the EXT input (Pin 6) should be tied to Vss (Pin 7). • R4, R5 and R6 set up the sensitivity of the SENS input. • R8 provides current limiting and isolation between the chip output and the triac gate. • C1 and L are RFI filter circuits.