LSI LS6505 Datasheet

LSI/CSI

U

L

®

A3800

LSI Computer Systems, Inc. 1235 Walt Whitman Road, Melville, NY 11747 [phone] FAX [phone]

LS6505

PIR SENSOR INTERFACE

FEATURES:

• Direct Interface with PIR Sensor

• Two-Stage Differential Amplifier

• Amplifier Gain and Bandwidth externally controlled

• Window Comparator and Digital Filter limit Noise

• Triac Output Drive

• Programmable Output Duration Timer

• Selectable Dead Time

• Single or Dual Pulse Detection

• Timing derived from 50Hz/60Hz AC

• Motion Detection LED Indicator

• LS6505 (DIP), LS6505-S (SOIC)- See Figure 1

APPLICATIONS:

Wall and ceiling mounted occupancy sensors providing
energy savings and convenience.

DESCRIPTION (See Figure 2)
The LS6505 is a CMOS integrated circuit, designed for detecting
motion from a PIR Sensor and initiating appropriate responses.

DIFFERENTIAL AMPLIFIER

Each stage of the two stage Differential Amplifier can be set to
have its own amplification and bandwidth. The two inputs to the
first stage allow for single ended or differential connection to PIR
Sensors. This stage can be biased anywhere in its dynamic range.
The second stage is internally biased so that the Window Compar­ator’s lower and higher thresholds can be fixed relative to this bias.

WINDOW COMPARATOR

The Window Comparator provides noise filtering by enabling only
those signals equal to or greater than a fixed threshold at the out­put of the Differential Amplifier to appear at the output of the
Window Comparator.

COMPARATOR DIGITAL FILTER

The output of the Window Comparator is filtered so that motion
must be present for a certain duration before it can be recognized
and appear as pulses at the Digital Filter output.

SINGLE PULSE / DUAL PULSE MODES

The logic level at the Pulse Mode Select input selects Single Pulse
(SP) or Dual Pulse (DP) mode. The trigger for the Output Duration
Timer is generated by requiring one (SP Mode) or two (DP Mode)
pulses to be present at the Digital Filter output within a specified
time period. SP Mode = 0; DP Mode = 1

OUTPUT DURATION TIMER (See Table 1 and Figure 3)
The timeout is selected by the voltage level at the Timer Control in­put. The Timer’s trigger is generated from pulses at the Digital filter
output. In Auto operation, the Timer controls the On duration of the
Triac output and is retriggerable.

DEAD TIME (See Table 2)
False turn-ons are prevented from occurring by establishing a
Dead Time between the end of the timeout of the Output Duration
Timer and the retriggering of that Timer.

6505-110602-1

November 2002

PIN ASSIGNMENT - TOP VIEW

VSS

VDD

1

LSI

2

3

4

5

6

7

8

LS6505

FIGURE 1

DIFF. AMP 1 INPUT (-)

16

DIFF. AMP 1 INPUT (+)

15

14

WARNING OUTPUT

TIMER CONTROL INPUT

13

DEAD TIME SELECT INPUT

12

OPERATION SELECT INPUT

11

PULSE MODE

10

SELECT INPUT
LED OUTPUT

9

DIFF. AMP. 1 OUTPUT

DIFF. AMP. 2 INPUT (-)

DIFF. AMP. 2 OUTPUT

MODE SELECT INPUT

AC INPUT

TRIAC OUTPUT

TRIAC OUTPUT

This open drain output turns On when the Output Duration
Timer is triggered. The output drives a Triac gate. With the Out­put Duration Timer On and a 2.7V P-P 60Hz signal applied to
the AC input, this output produces a negative going pulse in
each half-cycle delayed a nominal 1.2ms from the zero crossing.
There is no more than 150us difference between the zero­crossing delay of each pulse.

WARNING OUTPUT

This output goes high for 2 sec beginning 7.5 sec before the
Triac output turns off. This signal can be used to trigger an
audible or visual alert.

LED OUTPUT (See Figure 3)
Normally, the status of the LED output is opposite to the Triac
output, but in Auto operation the LED output flashes on for one
second whenever motion is detected.

MODE SELECT

Open = Mode A, Vss = Mode B, VDD = Mode C
OPERATION SELECT (See Figure 3, S1)

The 3-state Operation Select input determines the operation of
LS6505 in accordance with the selected Mode as shown below:

Input Mode A Mode B Mode C

VDD On (1) (3)

Open Auto Prior Condition Auto

Vss Off (2) (4)

(1) Momentary application of VDD turns on the Triac output and
starts Auto operation. After the Triac output is off for 15
seconds, Auto operation terminates.

(2) Momentary application of Vss turns off the Triac output.
(3) Same as (1) except that Auto operation does not terminate.
(4) Same as (2) except that after the Triac output is off for 8

seconds, Auto operation begins.

ABSOLUTE MAXIMUM RATINGS:
PARAMETER SYMBOL VALUE UNIT

DC supply voltage VDD - VSS +5.5 V
Any input voltage VIN VSS - 0.3 to VDD + 0.3 V
Operating temperature TA -40 to +85 °C
Storage temperature TSTG -65 to +150 °C

ELECTRICAL CHARACTERISTICS:

( All voltages referenced to VSS, TA = -40˚C to +55˚C, 4.5V ≤ VDD ≤ 5.5V, unless otherwise specified.)

PARAMETER SYMBOL MIN TYP MAX UNIT CONDITIONS
SUPPLY CURRENT:

VDD = 5V IDD - 150 200 µA Triac and LED
VDD = 4.5V - 5.5V IDD - 180 240 µA outputs not loaded

DIFFERENTIAL AMPLIFIERS:

Open Loop Gain, Each Stage G 70 - - dB ­Common Mode Rejection Ratio CMRR 60 - - dB ­Power Supply Rejection Ratio PSRR 60 - - dB ­Output Drive Current ID - - 25 µA -

Input Sensitivity VS 100 - - µV TA = 25˚C, with Amplifier
(Minimum Detectable Voltage Bandpass configuration
to first amplifier when both as shown in Figure 3
amplifiers are cascaded for
a net gain of 5,000)

Input Dynamic Range - 0 - 2.5 V -

Diff. Amp 2 Internal VIR - 0.4VR - V -

Reference

COMPARATOR:

Lower Reference VTHL - VIR - 0.5V - V ­Higher Reference VTHH - VIR + 0.5V - V -

DIGITAL FILTER:

Input Pulse Width TPW 66.3 - - ms 60Hz operation
(for recognition) TPW 79.6 - - ms 50Hz operation

OUTPUT DRIVE CURRENT:

Triac IO -40 - - mA With 3V Triac Gate
Warning: Source Current Iw + 2 - - mA Vo =VDD - 0.5V
Sink Current Iw - 1 - - mA Vo = 0.3V Max

TRIAC OUTPUT TIMING:

Pulse Width TTPW 20 30 45 µs VDD = 5V, f = 60Hz and
Delay from zero crossover TOD 1.00 1.2 1.32 ms 2.7V P-P AC input

Delay difference between TODD - - 150 µs f = 60Hz
zero crossovers

AC INPUT IMPEDANCE ZAC 270 - - kΩ ­LED OUTPUT:

Source Current IS+ 2 - - mA Vo = VDD - 0.5V
Sink Current IS- 1 - - mA Vo = 0.3V

Pulse Width TLPW 0.75 1 1.25 sec f = 60Hz
DUAL PULSE MODE:

Time between pulse-pairs TR - - 5.125 sec f = 60Hz
for motion recognition

6505-110102-2