LSI LS7211N

LSI/CSI
UL
®
LS7211N-7212N
LSI Computer Systems, Inc. 1235 Walt Whitman Road, Melville, NY 11747
(631) 271-0400 FAX (631) 271-0405
A3800
July 2009
PROGRAMMABLE DIGITAL DELAY TIMER
A
0
0
1
1
B
0
1
0
1
MODE
One-Shot (OS)
Delayed Operate (DO)
Delayed Release (DR)
Dual Delay (DD)
B
2
17 WB0
V DD (+V)
3
16 WB1
RC/CLOCK
4
RCS/CLKS
5
PSCLS
6
RESET
7
12 WB5
V SS (-V)
8
11 WB6
9
10 WB7
OUT
15 WB2
14
WB3
13 WB4
A
1
B
2
17 WB0
V DD (+V)
3
16 WB1
XTLI/CLOCK
4
15 WB2
XTLO
5
PSCLS
6
RESET
7
12 WB5
V SS (-V)
8
11 WB6
OUT
9
10 WB7
18 TRIG
LS7212N
TABLE 1. MODE SELECTION
1
LS7211N
I/O DESCRIPTION:
MODE SELECT Inputs A & B (Pins 1 & 2)
The 4 operating modes are selected by Inputs A and B
according to Table 1
18 TRIG
A
LSI
DESCRIPTION:
The LS7211N and LS7212N are CMOS integrated circuits for
generating digitally programmable delays. The delay is controlled by 8 binary weighted inputs, WB0 - WB7, in conjunction
with an applied clock or oscillator frequency. The programmed
time delay manifests itself in the Delay Output (OUT) as a function of the Operating Mode selected by the Mode Select inputs
A and B: One-Shot, Delayed Operate, Delayed Release or Dual
Delay. The time delay is initiated by a transition of the Trigger
Input (TRIG).
PIN ASSIGNMENT - TOP VIEW
LSI
FEATURES:
• 8-bit programmable delay from microseconds to days
• On chip oscillator (RC or Crystal) or external clock time base
• Selectable prescaler for real time delay generation based
on 50Hz/60Hz time base or 32,768Hz watch crystal
• Four operating modes
• Reset input for delay abort
• Low quiescent and operating current
• Direct relay drive
• +3V to +18V operation (VDD - VSS)
• LS7211N, LS7212N (DIP); LS7211N-S, LS7212N-S (SOIC)
- See Figure 1 -
14 WB3
13 WB4
FIGURE 1
Each input has an internal pull-up resistor of about 500kΩ.
One-Shot Mode (OS)
A positive transition at the TRIG input causes OUT to switch
low without delay and starts the delay timer. At the end of the
programmed delay timeout, OUT switches high. If a delay timeout is in progress when a positive transition occurs at the TRIG
input, the delay timer will be restarted. A negative transition at
the TRIG input has no effect.
Delayed Operate Mode (DO)
A positive transition at the TRIG input starts the delay timer. At
the end of the delay timeout, OUT switches low. A negative
transition at the TRIG input causes OUT to switch high without
delay. OUT is high when TRIG is low.
7211N-07209-1
Delayed Release Mode (DR)
A negative transition at the TRIG input starts the delay timer. At the end of the delay timeout, OUT switches high. A
postive transition at the TRIG input causes OUT to switch
low without delay. OUT is low when TRIG is high.
Dual Delay Mode (DD)
A positive or negative transition at the TRIG input starts
the delay timer. At the end of the delay timeout, OUT
switches to the logic state which is the inverse of the TRIG
input. If a delay timeout is in progress when a transition
occurs at the TRIG input, the delay timer is restarted.
TIMER RESET Input (RESET, Pin 7)
When RESET input switches high, any timeout in progress
is aborted and OUT switches high without delay. With RESET high, OUT remains high. When RESET switches low
with TRIG low in any mode, OUT remains high. When RESET switches low with TRIG high in Delayed Operate and
Dual Delay modes, the delay timer is started and OUT
switches low at the end of the delay timeout. When RESET switches low with TRIG high in Delayed Release
mode, OUT switches low without delay. When RESET
LS7211N TIME BASE Input (RC/CLOCK, Pin 4)
For LS7211N, the basic timing signal is applied at the RC/ switches low with TRIG high in One-Shot mode, OUT reCLOCK input. The clock can be provided from either an ex- mains high. RESET input has an internal pull-down resistor
ternal source or generated by an internal oscillator by con- of about 500kΩ, and is buffered by a Schmitt Trigger to
provide input hysteresis.
necting an R-C network to this input.
The frequency of oscillation is given by ƒ 1/RC. Chip-toVSS (-V, Pin 8)
chip oscillation tolerance is ± 5% for a fixed value of RC.
Supply voltage negative terminal or GND.
The minimum resistance, R MIN = 4000Ω, VDD = + 4V
= 1200Ω, VDD = +10V
DELAY Output (OUT, Pin 9)
= 600Ω, VDD = +18V
Except in One-Shot mode, OUT switches with or without
The external clock mode is selected by applying a logic low delay (depending on mode) in inverse relation to the logic
to the RCS/CLKS input (Pin 5); the internal oscillator mode is level of the TRIG input. In One-Shot mode, a timed low
level is produced at OUT, in response to a positive transiselected by applying a high level to the RCS/CLKS input.
tion of the TRIG input.
LS7212N TIME BASE Input (XTLI/CLOCK, Pin 4)
For LS7212N, the basic timing clock is applied to the XLTI/ WEIGHTING BIT Inputs (WB7 to WB0, Pins 10 - 17)
CLOCK input from either an external clock source or gener- Inputs WB0 through WB7 are binary weighted delay bits
ated by an internal crystal oscillator by connecting a crystal used to program the delay according to the following
relations:
between XTLI/CLOCK input and the XTLO output (Pin 5).
TRIGGER Input (TRIG, Pin 18)
A transition at the TRIG input causes OUT to switch with or
without delay, depending on the selected mode. The TRIG input to OUT transition relation is always opposite in polarity,
with the exception of One-Shot mode. (See Mode definitions
above.) TRIG input has an internal pull-down resistor of
about 500k Ω and is buffered by a Schmitt trigger to provide
input hysteresis.
One-Shot Mode: Pulse width = SW
LS7211N TIME BASE SELECT Input (RCS/CLKS, Pin 5)
ƒ
For LS7211N, the external clock operation at Pin 4 is selected by applying a logic low to the RCS/CLKS input. The internal oscillator option with RC timer at Pin 4 is selected by All other Modes: Delay = SW + 0.5
ƒ
applying a logic high at the RCS/CLKS input. RCS/CLKS inWhere:
put has an internal pull-down resistor of about 500kΩ.
S = Prescale factor (See Table 2)
ƒ = Time base frequency at Pin 4
LS7212N TIME BASE Output (XTLO, Pin 5)
For LS7212N, when a crystal is used for generating the time W = WB0 + WB1 + ....... WB7
base oscillation, the crystal is connected between XTLI/
The weighting factor W is calculated by substituting in the
CLOCK and XTLO pins.
equation above for W, the weighted values for all the WB
inputs that are at logic high. The weighted values for the
PRESCALER SELECT Input (PSCLS, Pin 6)
The PSCLS input is a 3-state input, which selects one of WB inputs are shown in Table 3. Each WB input has an internal pull-down resistor of about 500kΩ.
three prescale factors according to Table 2.
TABLE 2. PRESCALE FACTOR SELECTION
PSCLS Input
Logic Level
Float
VSS
VDD
S (Prescale Factor )
LS7211N
LS7212N
1
1
3,000
32,768
3,600
32,768x60
Using prescale factors of 3000 and 3600, delays in units of
minutes can be produced from 50Hz and 60Hz line sources.
Prescale factors of 32,768 and 32,768 x 60 can be used to
generate accurate delays in units of seconds and minutes,
respectively, from a 32kHz watch crystal.
7211N-062209-2
TABLE 3. BIT WEIGHTS
BITS
WB0
WB1
WB2
WB3
WB4
WB5
WB6
WB7
VDD (+V, Pin 3)
Supply voltage positive terminal.
VALUE
1
2
4
8
16
32
64
128
ABSOLUTE MAXIMUM RATINGS: (All voltages referenced to VSS)
SYMBOL
VALUE
DC Supply Voltage
VDD
+19
Voltage (Any Pin)
VIN
VSS - 0.3 to VDD + 0.3
Operating Temperature
TA
-20 to +85
Storage Temperature
TSTG
-65 to +150
UNIT
V
V
°C
°C
ELECTRICAL CHARACTERISTICS (Voltages referenced to Vss)
Characteristic
SYMBOL
Supply Voltage
VDD
Supply Current
IDD
Input Voltages:
Reset, Trigger Low
VTL
Reset, Trigger High
VTH
Reset, Trigger Hysteresis
All other inputs, Low
VIL
All other inputs, High
VIH
Input Currents:
PSCLS Low
IPL
PSCLS High
IPH
A, B Low
IML
A, B High
All other inputs, Low
IMH
IIL
All other inputs, High
IIH
Output Current:
OUT Sink
IOSNK
OUT Source
IOSRC
7211N-072009-3
3.0
10.0
18.0
Min
3.0
-
-20°C
Max
18.0
66
252
540
Min
3.0
-
+25°C
Max
18.0
55
210
450
Min
3.0
-
+85°C
Max
18.0
44
168
360
3.0
10.0
18.0
3.0
10.0
18.0
3.0
10.0
18.0
3.0
10.0
18.0
3.0
10.0
18.0
2.2
6.1
9.7
0.7
2.2
3.9
1.9
6.5
13.3
0.8
2.3
3.9
1.1
4.5
10.6
-
2.1
6.0
10.5
0.7
2.2
3.9
1.9
6.5
13.3
0.75
2.2
3.8
1.1
4.5
10.6
-
2.0
5.9
11.0
0.7
2.2
3.9
1.9
6.5
13.3
0.7
2.1
3.7
1.1
4.5
10.6
-
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
3.0
10.0
18.0
3.0
10.0
18.0
3.0
10.0
18.0
3.0
10.0
18.0
-
3.2
31
84
9.8
31
85
6.0
59
157
100
100
33
120
121
-
2.5
24
65
7.5
24
65
5.0
48
128
100
100
27
105
107
-
1.9
18
49
5.8
18.2
49
4.0
38
98
200
200
23
81
82
µA
µA
µA
µA
µA
µA
µA
µA
µA
nA
nA
µA
µA
µA
3.0
10.0
18.0
3.0
10.0
18.0
13.2
26
30.7
4.1
7.2
8.2
-
10.1
19.7
23.6
3.2
5.5
6.3
-
7.0
15
17
2.1
4.1
4.6
-
mA
mA
mA
mA
mA
mA
VDD
Unit
V
µA
µA
µA
Condition
with the clock off and
all inputs floating.
-
Input at VSS
Input at VDD
Input at VSS
Input at VDD
Input at VSS
Input at VDD
Vo = +0.5V
Vo = VDD - 0.5V
ELECTRICAL CHARACTERISTICS (Voltages referenced to Vss) (Con’t)
Characteristic
SYMBOL
Switching Characteristics (See Fig. 3)
RC Oscillator Frequency
fosc
External Clock or
Crystal Oscillator
Frequency
fext
fext
TRIG Set-Up Time
A, B Set-Up Time
WB0 - WB7 Set-Up Time
t1
t2
t3
Clock to Out Delay
t4
VDD
3.0
10.0
18.0
3.0
10.0
18.0
3.0
10.0
18.0
Max
Min
Max
Min
Max
-
1.8
4.5
8.0
2.6
5.3
5.9
7.2
16.0
15.9
-
1.4
3.4
4.0
2.0
4.0
4.5
5.5
12.8
13.0
-
1.05
2.6
3.0
1.52
3.0
3.5
4.2
9.7
9.1
MHz
MHz
MHz
MHz
MHz
MHz
MHz
MHz
MHz
39
0
0
-
284
98
87
50
0
0
-
375
130
115
66
0
0
-
495
172
152
ns
ns
ns
ns
ns
ns
-
3.0
10.0
18.0
Unit
Min
Condition
For prescale
factor S = 1 or 3,000
or 3,600
S = 32,768
or
32,768 x 60
CL = 50pF
+V
500k
A 1
MODE
REG
+V
500k
B 2
EDGE
DETECT
TRIG 18
CONTROL
LOGIC
LATCH
9
BUF
OUT
500k
RESET 7
CLOCK/RC/XTLI
500k
4
CLOCK
LATCH/TIMER
8
10-17
500k
MUX
OSC
PRESCALER
XTLO (LS7212N) 5
RCS/CLKS (LS7211N)
5
500k
+V
+V
1M
PSCLS 6
-V (Gnd)
3-STATE
DECODER
1M
FIGURE 2. LS7211N / LS7212N BLOCK DIAGRAM
7211N-072009-4
(8)
3
VDD
8
VSS
WB7-WB0
t0
Clock
t1
t1
TRIG
t2
A = 0, B = 1, Delayed Operate
A, B
Programmed Delay
t3
t4
WB0-WB7
OUT
Immediate Release
Note 1. TRIG input is clocked in by the negative edge of external clock.
Note 2. Inputs A, B and WB0 - WB7 are sampled only at a TRIG input transition and ignored at all other times.
Note 3. OUT is switched by the positive edge of the external clock.
FIGURE 3. INPUT/OUTPUT TIMING
TRIG
F
RESET
OUT(OS)
C
OUT(DO)
OUT(DR)
D
OUT(DD)
G
A
B
H
E
A. Turn-on delay in DO and DD modes; Pulse-width in OS mode.
B. Turn-off delay in DR and DD modes.
C. Pulse-width extended by re-trigger in OS mode.
No effect in DO and DD modes because TRIG switches back low before turn-on delay has timed out.
D. Turn-off delay in DR mode.
E. Turn-on delay in DO and DD modes; pulse-width in OS mode.
F. No effect in DO, DR and DD modes because of TRIG’s switching back to opposite levels.
G. Time-outs aborted and OUT forces high by RESET.
H. After the removal of RESET, OUT switches to the inverse polarity of TRIG
immediately (DR) or after the timeout (DO, DD). No effect in OS.
FIGURE 4. MODE ILLUSTRATION WITH TRIG, OUT AND RESET
7211N-061906-5
+V
470k
3
VDD
+V
5
25pF
5
CRYSTAL
XTLO
10M
RCS/CLKS
LS7211N
LS7212N
4
4
XTLI
CLOCK
25pF
10k
ƒ
4
0.1µF
4
RC
CLOCK
LS7212N
LS7211N
FIGURE 6. MULTI-TIMER WITH SINGLE CRYSTAL TIME-BASE
+V
V SS
3
8
ƒ=
V DD
1
-6
10 x 10 x 0.1 x 10 = 1kHz
LS7211N
3
1M
4
120VAC
CLOCK
200pF
FIGURE 5. RC- Oscillator Connection
V SS
8
FIGURE 7. DRIVING CLOCK INPUT FROM THE AC LINE
+V
3
V DD
*
*
8
10-17
2
1, 2
3
*
*
WB0-WB7
A, B
LS7211N
18
TRIGGER
4
ƒ
TRIG
8
2
10-17
WB0-WB7
1, 2
A, B
LS7211N
OUT
9
CLOCK
18
4
TRIG
OUT
CLOCK
Vss
8
*
Connect for desired delay and mode
FIGURE 8. DELAY EXTENSION BY CASCADING
7211N-062209-6
V DD
Vss
8
9
OUT
1
2
TRIGGER IN
18
4
25pF
ƒ
25pF
470k
+V
S1
+V
A
V DD
B
WB0
TRIG
WB1
XTLI
WB2
WB3
10M
5
6
WB4
XTLO
WB5
WB6
PSCLS
WB7
+V
7
8
OUTPUT
9
LS7212N
RESET
3
17
1s/1m
16
2s/2m
15
4s/4m
14
8s/8m
13
16s/16m
12
32s/32m
11
64s/64m
10
128s/128m
s = seconds
m = minutes
Vss
OUT
NOTE : Crystal Frequency, ƒ = 32,768Hz
Switch: S1 low: Delay increment = 1s; Maximum Delay = 255s
S1 high: Delay increment = 1m; Maximum Delay = 255m
FIGURE 9. PROGRAMMABLE ACCURATE REAL-TIME DELAY GENERATION
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.
7211N-052606-7
+V
3
1
2
V DD
A
B
WB0
WB1
WB2
4
ƒi
+V
7
CLOCK
LS7212N
9
WB4
RESET
WB5
TRIG
WB6
18
ƒo
WB3
OUT
WB7
17
16
15
14
13
12
11
10
Vss
8
CASE 1. MODE = DO or DR; PRESCALE FACTOR, S = 1
In this setup a frequency division of the input clock, ƒi by a factor of 2 to 257, in increments of 1 can
be obtained according to the equation:
ƒo =
ƒi
W+2
where W (weighting factor) = 0 to 255
The ƒo pulse width is non-symmetrical (non-50% duty -cycle)
CASE 2. MODE = DD; PRESCALE FACTOR, S = 1
In this setup a frequency division of the input clock, ƒi by a factor of 2 to 512, in increments of 2 can
be obtained according to the equation:
ƒo =
ƒi
2 (W + 1)
where W (weighting factor) = 0 to 255
The ƒo pulse widths are symmetrical with 50% duty -cycle
EXAMPLES OF CASE 1 and CASE 2 FREQUENCY DIVISIONS WITH W = 2
ƒi
ƒo
Case 1, Mode = DO;
÷4
ƒo
Case 2, Mode = DD;
÷6
FIGURE 10. PROGRAMMABLE FREQUENCY DIVIDER
7211N-052606-8