RE46C165 Microchip Technology Inc., RE46C165 Datasheet - Page 15

• Manufacturer Part Number: RE46C165
• Description: Cmos Photoelectric Smoke Detector Asic With Interconnect, Timer Mode And Alarm Memory
• Manufacturer: Microchip Technology Inc.

TABLE 3-1:
FIGURE 3-1:
 2010 Microchip Technology Inc.
Pin Name
HORNB
COSC
VSEN
FEED
LED
I/O
Oscillator
Internal Clock
STROBE
IRED
LED
LED
STROBE
Horn
STROBE
Horn
DIAGNOSTIC MODE PIN FUNCTION
Number
Low Batt eryWarning Chirp
Pin
15
10
12
11
8
7
RE46C165/6/7/8 Timing Diagram – Standby, Low Battery, Chamber Fail.
Chamber Test and Warning is Offset from Low Battery Test and Warning by 21.3 Seconds.
T
POSC
Disabled as an output. A high on this pin directs the photo amplifier output to pin C1 or
C2, determined by the level on VSEN. Amplification occurs during the IRED active time.
If I/O is high, then this pin controls the gain capacitor that is used. If VSEN is low, the
normal gain is selected and the photo amplifier output appears on C1. If VSEN is high,
high gain is selected, and the photo amplifier output is on C2.
10% gain increase in normal gain mode.
If desired, this pin can be driven by an external clock.
This pin becomes the smoke integrator output. A high level indicates that an alarm con-
dition has been detected.
The LED pin is used as a low battery indicator. For V
old, the open drain NMOS is off. If V
If VSEN is low, then taking this input high will enable hysteresis, which is a nominal
T
ST ON
Low Batt eryTest
T
HON2
Low Bat t ery Test
Chamber Fail Test
Standby, No Alarm (not to Scale)
Low Supply Test Failure
Chamber Fail Test Failure
T
HOF4
T
T
T
PER6
IRON
IRON
T
PLED1
T
T
T
T
HPER2
HPER2
PER0
HOF3
DD
T
Function
falls below the threshold, the NMOS turns on.
HOF5
RE46C165/6/7/8
DD
T
HON2
above the low battery thresh-
DS22251A-page 15