LSI/CSI UL ® LS7213 LSI Computer Systems, Inc. 1235 Walt Whitman Road, Melville, NY 11747 (631) 271-0400 FAX (631) 271-0405 A3800 February 2006 PROGRAMMABLE DIGITAL DELAY TIMER DESCRIPTION The LS7213 is a CMOS integrated circuit for generating programmable time-delays. The delay is initiated by a logic transition at the Trigger input and the completion of the delay is marked by a change of status at the Out1 and the Out2 outputs. Three inputs, D1, D2 and D3 select 1-of-8 scale factors, s. The delay, td is related to s by the expression, t d = s/frc, where frc is the frequency at the RC input produced by an internal oscillator. An external resistorcapacitor pair connected to the RC pin controls the oscillator frequency. There are four modes of operation selected by inputs A and B. The operating modes are: On-Delay (OND), Off-Delay (OFD), Dual-Delay (DLD) and One-Shot (OST). These modes are described below: On-Delay (OND) Mode A positive transition at the Trigger input starts the on-delay timer. At the end of the delay, Out1 switches low and Out2 switches high. A negative transition at the Trigger input immediately aborts any ondelay in progress. If the Trigger input is switched low, Out1 if low will switch high and Out2 if high will switch low without delay. The states of Out2 in the preceding description applies only if Flashen input is low at the time of the Trigger input transition. See the Out2 pin section for a complete description. Off-Delay (OFD) Mode A negative transition at the Trigger input starts the off-delay timer. At the end of the delay, Out1 switches high and Out2 switches low. A positive transition at the Trigger input immediately aborts any offdelay in progress. If the Trigger input is switched high, Out1 if high will switch low and Out2 if low will switch high without delay. The states of Out2 in the preceding description applies only if FlashEn input is low at the time of the Trigger input transition. See the Out2 pin section for a complete description. 14 V DD (+V) D3 1 D2 2 13 OUT1 D1 3 12 OUT2 FLASHEN 4 11 RESET 10 RC LS7213 APPLICATIONS Time delay relays for HVAC equipment and industrial controls. PIN ASSIGNMENT TOP VIEW LSI FEATURES: • Eight timing ranges • Four modes • RC controlled on-chip oscillator • Power-On-Reset (POR) • Reset input for delay abort • Complementary outputs • Delay-in-Progress Indicator output • LS7213 (DIP), LS7213-S (SOIC) - See Figure 1 A 5 B 6 9 CAP 7 8 TRIGGER V SS (-V) FIGURE 1 One-Shot (OST) Mode A positive transition at the Trigger input causes Out1 to switch low and Out2 to switch high immediately and start the one-shot delay timer. At the end of the delay Out1 switches high and Out2 switches low. Thus in effect, a positive transition at the Trigger input produces a negative pulse at Out1 and a positive pulse at Out2. The one-shot delay timer is restarted with every positive trigger transition, thus rendering the Out1 and Out2 pulse-widths stretchable to any duration by periodic re-trigger. A negative transition at the Trigger input has no effect. The states of Out2 in the preceding description applies only if FlashEn input is low at the time of the Trigger input transition. See the Out2 pin section for a complete description. INPUTS/OUTPUTS Following is a description of all the input/output pins and their functions. Delay Select Inputs: D1, D2, D3 (Pin 3, Pin 2, Pin 1) The logic states applied to these three inputs enable the user to select a scale factor, s, for generating a delay, td, fromTrigger input to Out1/Out2 outputs according to Table1. The delay is given by the expression: td = s/frc, where, s is the scale factor, and frc is the oscillator frequency at the RC input. The sample delays in Table1 are based on an oscillator frequency, frc = 10kHz. TABLE 1. Delay Selection D3 D2 D1 s td ( = s/frc) Dual-Delay (DLD) Mode 3 0 0 0 1x10 0.1sec In Dual-Delay mode, the delay is generated for both positive and 0 0 1 1x104 1.0sec negative transitions at the Trigger input. A positive transition at the 5 0 1 0 1x10 10.0sec Trigger input starts the on-delay timer and aborts any off-delay tim0 1 1 60x103 0.1min ing in progress. At the end of the delay Out1 switches low and Out2 1 0 0 60x104 1.0min switches high. A negative transition at the Trigger input starts the 1 0 1 60x105 10.0min off-delay timer and aborts any on-delay timing in progress. At the 1 1 0 3600x103 0.1hr end of the delay Out1 switches high and Out2 switches low. The 1 1 1 3600x104 1.0hr states of Out2 in the preceding description applies only if Flashen input is low at the time of the Trigger input transition. See the Out2 pin D1, D2 and D3 inputs have internal pull-down resistors. section for a complete description. 7213-022706-1 Mode Select Inputs: A, B (Pin 5, Pin 6) The four operating modes are selected by inputs A and B cording to Table 2. ac- TABLE 2. Mode Selection A 0 0 1 1 B 0 1 0 1 Mode On-Delay (OND) Off-Delay (OFD) Dual-Delay (DLD) One-Shot (OST) Inputs A and B have internal pull-down resistors. Driver Outputs: Out1, Out2 (Pin 13, Pin 12) Out1 is an output for driving DC loads requiring high current sink, such as relays, power transistors, etc. In steady-state condition Out1, with the exception of one-shot mode, is always inverse in polarity with respect to the Trigger input. Depending on the operating mode, the steady-state condition is reached immediately or after a specified delay following a change of state at the Trigger input. In one-shot mode, Out1 is always at logic high in the steady state, independent of the logic state of the Trigger input. Out2 operates in two different modes depending on the state of the FlashEn input. If Flashen is at logic low then: Out2 operates exactly as Out1 but with inverse polarity. In this mode, Out2 is an output for driving DC loads requiring high current source, such as relays, power transistors, etc. In steady-state condition Out2, with the exception of one-shot mode, is always at the same polarity as the Trigger input. Depending on the operating mode, the steady-state condition is reached immediately or after a specified delay following a change of state at the Trigger input. In one-shot mode Out2 is always at logic low in the steady state, independent of the logic state of the Trigger input. If Flashen is at logic high then: Out2 operates as a delay-in-progress indicator by generating periodic positive pulses during a delay timing. The pulse-rate, fpf and the pulse-width tpf at Out2 is controlled by an internal oscillator whose frequency, fcf, is set by a capacitor connected to the Cap input. fpf and fcf are related by the following expressions: fpf = 20/fcf, for scale factors 1x103 and 1x104 and fpf = 100/fcf, for all other scale factors. The pulse-width, tpf for both pulse-rates is given by: tpf = 2/fcf At the end of timeout, Out2 returns to logic low with the cessation of pulses. Flash Enable Input: FlashEn (Pin 4) The FlashEn input modifies the operation of Out2 to function in one of two modes. When FlashEn = 0, Out2 functions exactly as Out1 but with inverse polarity from Out1. When FlashEn = 1, Out2 functions as a flashing delay-in-progress indicator. In this mode periodic positive pulses are generated at Out2 during a delay timing which can be used to produce a flashing LED display for user feedback. For a complete description see Out2 section on Page 2. The Fashen input has an internal pull-down resistor. Master Clear Input: Reset (Pin 11) When Reset is brought to logic high, all timing functions are aborted, the timer is cleared, Out1 is forced high and Out2 is forced low. Switching the Reset input low causes the mode select inputs, the delay select inputs, the FlashEn input and the Trigger input to be sampled by internal logic. Following this, any inconsistencies between the Trigger input and the Out1 and Out2 outputs are resolved and the steady state is reached with or without delay based on the status of the mode select inputs. For example, if the Trigger input is high, the FlashEn input is low and the mode is off-delay when the Reset input is switched from high to low, Out1 and Out2 will immediately be switched low and high, respectively, from its forced reset condition. In this example if the mode is on-delay instead of off-delay, then Out1 and Out2 will be switched after the completion of the programmed delay td. It should be noted here that the states of Out1 and Out2 in the reset condition and One-Shot mode steady state condition are the same namely, Out1 = 1 and Out2 = 0. Because of this, in one-shot mode, no change in Out1 and Out2 takes place when the Reset input is switched low, irrespective of the status of the Trigger input. The Reset input has an internal pull-down resistor. NOTE: A POR circuit (See Fig. 2) generates a reset upon power up that produces the same conditions described for Reset (Pin 11). Timer Oscillator Input: RC (Pin 10) A resistor-capacitor pair connected to the RC input serves as the basic timing element for the delay timer oscillator. The oscillator frequency is given by the expression: frc = 1/0.9RC, where R and C are the resistor and the capacitor values at the RC input. The delay, td, is given by the expression: td = s/frc, where s is the scale factor selected by inputs D1, D2 and D3. Flash Oscillator Input: Cap (Pin 9) A capacitor, C, connected from the Cap input to ground regulates an internal flash oscillator frequency according to the relation: fcf = (k/C) x 10-6 Timer Start Input: Trigger (Pin 8) Any logic transition at the Trigger input, positive or negative causes where k is a V DD dependent constant ranging in value between 2.1 at V DD = 3V to 4.8 at V DD = 5V. The flash oscillator frequency the outputs Out1 and Out2 to switch with or without delay, decontrols the pulse-rate, f pf and the pulse width, t pf at Out2 in flash pending on the operating mode. mode according to the following relationships: fpf = 20/fcf, Any transition of the Trigger input also causes the logic states of the following inputs to be strobed into internal latches: A, B, D1, D2, D3 for scale factors 1x103 and 1x104 and and FlashEn. This prevents any changes at any of these inputs from fpf = 100/fcf, disrupting the timer when a timeout is in progress. for all other scale factors; and for the pulse-width, See the description of modes on Page1 and Out1, Out2 section on tpf = 2/fcf, for all scale factors. Page 2 for a complete description of the Trigger input. Chip to chip tolerance of fcf is +/- 10% at fixed VDD. TheTrigger input has an internal pull-down resistor. Power Supplies VDD, Vss (Pin 14, Pin 7) Note: LS7213 is not suited for applications requiring direct feedback VDD is the power supply positive terminal and Vss is the negative of OUT1 to the Trigger input for generating sustained oscillation. or ground terminal. 7213-011706-2 ABSOLUTE MAXIMUM RATINGS: (All voltages referenced to VSS) SYMBOL VDD VIN TA TSTG DC Supply Voltage Voltage (Any Pin) Operating Temperature Storage Temperature VALUE +7 VSS - 0.3 to VDD + 0.3 -20 to +85 -65 to +150 UNIT V V °C °C ELECTRICAL CHARACTERISTICS (Voltages referenced to Vss unless specified otherwise) Characteristic SYMBOL Supply Voltage VDD Supply Current IDD 3 4 5 Min 3.0 - -20°C Max 5.5 75 125 190 Min 3.0 - +25°C Max 5.5 65 100 150 Min 3.0 - +85°C Max 5.5 50 85 140 3 4 5 3 4 5 3 4 5 3 4 5 - 1.6 2.0 2.7 0.8 1.2 1.5 1.5 1.9 2.4 - 1.0 1.3 1.6 1.6 2.0 2.7 0.8 1.2 1.5 0.4 0.5 0.5 1.5 1.9 2.4 - 2.0 2.6 3.3 1.2 1.8 2.1 1.2 1.4 1.8 1.0 1.3 1.6 1.6 2.0 2.7 0.8 1.2 1.5 1.5 1.9 2.4 - 1.0 1.3 1.6 V V V V V V V V V V V V V V V 3 4 5 0.9 3.5 8.0 5 2.5 6.0 12.0 0.8 3.0 7.0 5 2.0 5.0 10.0 0.5 2.0 5.0 10 1.6 4.0 8.0 nA µA µA µA 3 4 5 3 4 5 3 4 5 3 4 5 12.0 14.0 18.0 1.8 3.0 3.5 5.4 7.8 9.0 9.0 13.0 15.0 - 10.0 12.0 15.0 1.5 2.5 3.0 4.5 6.5 7.5 8.0 11.0 13.0 - 7.0 9.0 10.0 1.0 1.6 2.0 3.0 4.5 5.5 6.0 8.0 9.0 - mA mA mA mA mA mA mA mA mA mA mA mA 3 4 5 6.8k 4.7k 3.9k 6.0 10M 10M 10M 8.2k 5.6k 4.7k 5.0 10M 10M 10M 10.0k 6.8k 5.6k 4.0 10M 10M 10M MHz Ω Ω Ω - VDD Unit V µA µA µA Condition with oscillators off Input Voltages: Trigger High VTH Trigger Low VTL Trigger Hysteresis All other inputs, High VIH All other inputs, Low VIL Input Currents: All inputs, Low IIL All inputs, High IIH - - - - - Input at VSS Input at VDD Output Current: OUT1 Sink IO1L VO1 = +0.5V OUT1 Source IO1H OUT2 Sink IO2L OUT2 Source IO2H RC Oscillator: Frequency Resistor frc R Capacitor C - no limit no limit no limit µF - Capacitor C - no limit no limit no limit µF - Constant K 3 4 5 2.1 3.2 4.3 - - VO1 = VDD - 0.5V VO2 = +0.5V VO2 = VDD - 0.5V Flash Oscillator: 7213-082101-3 2.5 3.2 4.8 2.1 3.2 4.3 2.5 3.7 4.8 2.1 3.2 4.3 2.5 3.7 4.8 The information included herein is believed to be accurate and reliable. LSI Computer Systems, Inc. assumes no responsibilities for inaccuracies, nor for any infringements of patent rights of others which may result from its use. D3 1 LATCH D2 2 LATCH D1 3 LATCH RC 10 OUTPUT DRIVER TIMER RANGE DECODER OUTPUT DRIVER 5 LATCH B 6 LATCH FLASHEN 4 LATCH TRIGGER 8 LATCH 12 O U T 2 POR GENERATOR OSC A 13 O U T 1 OSC 9 CAP CONTROL LOGIC 11 R E S E T FIGURE 2. LS7213 BLOCK DIAGRAM +V 14 VDD -V 7 Vss FIGURE 3. MODE ILLUSTRATION WITH TRIG, OUT1 AND RESET TRIG F RESET C OUT1(OST) OUT1(OND) D OUT1(OFD) OUT1(DLD) G A H E B A. Turn-on delay in OND and DLD modes; Pulse-width in OST mode. B. Turn-off delay in OFD and DLD modes. C. Pulse-width extended by re-trigger in OST mode. No effect in OND and DLD modes because TRIG switches back low before turn-on delay has timed out. D. Turn-off delay in OFD mode. E. Turn-on delay in OND and DLD modes; pulse-width in OST mode. F. No effect in OND, OFD and DLD modes because of Trig’s switching back to opposite levels. G. Time-out aborted and OUT1 forced high by RESET. H. After the removal of RESET, OUT1 switches to the inverse polarity of TRIG immediately (OFD) or after the timeout (OND, DLD). No effect in OST. +5V The table below shows the delays obtained with the following components R1 = 56kΩ, R2 = 500kΩ and C2 = 0.002µF. At any scale factor, the delay changes from minimum to maximum as the potentiometer, R2 is varied from minimum to maximum. R2 1 D3 2 D2 3 D1 V DD (+V) 14 R1 13 OUT1 OUT2 12 300 11 RESET 4 FLASHEN 5 RC A LS7213 6 B 7 Vss(-V) 10 LED 9 CAP C2 8 C1 D3 0 0 0 0 1 1 1 1 D2 0 0 1 1 0 0 1 1 D1 0 1 0 1 0 1 0 1 TIMING RANGE 0.1 sec - 1 sec. 1 sec. - 10 sec. 10 sec - 100 sec. 0.1 min. to 1 min. 1 min. - 10 min 10 min. - 100 min. 0.1 hr. - 1 hr. 1 hr. - 10 hr. TRIGGER INPUT RESET INPUT FIGURE 4. TYPICAL APPLICATION WITH OUT1 AS RELAY DRIVE AND OUT2 AS FLASHER 7213-090100-4 C1 = 0.22µF, produces flash pulses of 0.1 sec duration at Out2