- 您现在的位置：买卖IC网 > PDF目录11652 > A5348CA (Allegro Microsystems Inc)IC SMOKE DETECTOR ION 16-DIP PDF资料下载
参数资料
| 型号： | A5348CA |
| 厂商： | Allegro Microsystems Inc |
| 文件页数： | 6/9页 |
| 文件大小： | 0K |
| 描述： | IC SMOKE DETECTOR ION 16-DIP |
| 标准包装： | 25 |
| 类型： | 烟雾探测器 |
| 输入类型： | 离子化 |
| 输出类型： | 电压 |
| 电流 - 电源： | 12µA |
| 安装类型： | 通孔 |
| 封装/外壳： | 16-DIP（0.300"，7.62mm） |
| 供应商设备封装： | 16-DIP |
| 包装： | 管件 |
Ionization Smoke Detector
with Interconnect and Timer
A5348
6
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
SENSITIVITY SET and VSS, with the value:
RSENSITIVITYSET = 1.1E6 × K / (1 – K) ,
where
K = 1 / (VDD / VSENSITIVITYSET – 1) .
Low Battery
The low battery condition threshold is set internally by a voltage
divider connected between VDD and VSS. The threshold can
be externally adjusted by connecting a resistor between the
LOW-V SET pin and either the VDD or VSS pins.
To increase the threshold, a resistor can be connected between
LOW-V SET and VSS. Given an initial threshold, V(th)init (nomi-
nally 7.5 V), and a target threshold, V(th)set, the resistor should
have the value:
RLOWVSET = 600E3 × K / (1 – 0.375 × K) ,
where
K = 1 / (V(th)set / [0.727 × V(th)init] – 1) .
To decrease the threshold, a resistor can be connected between
LOW-V SET and VDD. Given an initial threshold, V(th)init (nomi-
nally 7.5 V), and a target threshold, V(th)set, the resistor should
have the value:
RLOWVSET = 960E3 × K / (0.6 – 1.6 × K) ,
where
K = V(th)set / (0.727 × V(th)init) – 1 .
The battery voltage level is checked approximately every 40 sec-
onds during the (approximately) 10 mA, 10 ms LED pulse. If an
LED is not used, it should be replaced with an equivalent resistor
(typically 500 to 1000 Ω) such that the battery loading remains
about 10 mA.
Timer (Hush) Mode
An internal timer is provided that can be used in various configu-
rations to allow a period of reduced smoke detector sensitivity,
referred to as Timer (or Hush) mode.
In normal operation, when a high-to-low transition occurs at the
TIMER START pin, the internal timer is reset, Timer mode is
enabled, and the circuit resets to a no-alarm condition. During
Timer mode, which is active for approximately 10.25 minutes
(368 clock cycles), the TIMER OUT pin is pulled down to VSS
every time the A5348 makes a check for smoke. A resistor con-
nected between the TIMER OUT and the SENSITIVITY SET
pins will decrease the detector’s sensitivity to smoke during
this time, and allow the user to hush alarms caused by nuisance
smoke or steam (such as from cooking). At the end of Timer
mode, the device signals its completion with two 10-ms horn
chirps, 1.67 seconds apart.
While the Timer mode is active, the LED flashes once every
(approximately) 10 seconds. If the level of smoke increases such
that the reduced-sensitivity level is reached, the A5348 will signal
an Alarm condition. If such an Alarm condition does occur, the
timer will still continue to completion of its cycle. If Timer mode
will not be used, the TIMER START pin can be tied to VSS or
left open.
I/O
A connection to the I/O pin allows multiple smoke detectors to
be interconnected. If any single unit detects smoke, its I/O pin is
driven high (after a nominal 3 s delay), and all connected units
will sound their associated horns. When the I/O pin is driven
high by another device, the oscillator immediately speeds up to
its 41.7 ms period. The remainder of the sped-up clock cycle,
and two additional consecutive clock cycles with I/O high are
required to cause an alarm. If the I/O pin falls below its threshold
at any time during those (approximately) 83.4 ms, an internal
latch is reset and there will not be an alarm. Thus, the I/O must
remain high for (approximately) 93.9 ms in order to cause an
alarm. This filtering provides significant immunity to I/O noise.
The LED is suppressed when an alarm is signaled from an inter-
connected unit, and any local alarm condition causes the I/O pin to
be ignored as an input. When in Timer mode, the device will still
signal an alarm if I/O is driven high externally. This pin has an on-
chip pulldown device and must be left unconnected if not used.
Testing
On power-up, all internal counters are reset. Internal test cir-
cuitry allows low battery check by holding the FEEDBACK and
OSC CAP pins low during power-up, then reducing VDD and
monitoring the HORN1 pin. HORN1 will be driven high when
VDD falls below the low-battery threshold. All functional tests
can be accelerated by driving the OSC CAP pin with a 2 kHz
square wave. The 10 ms strobe period must be maintained for
proper operation of the comparator circuitry.
相关PDF资料 |
PDF描述 |
|---|---|
| VI-JN4-IY-F4 | CONVERTER MOD DC/DC 48V 50W |
| VI-JN4-IY-F2 | CONVERTER MOD DC/DC 48V 50W |
| VI-JN4-IY-F1 | CONVERTER MOD DC/DC 48V 50W |
| VI-JN3-IY-F4 | CONVERTER MOD DC/DC 24V 50W |
| VI-JN3-IY-F2 | CONVERTER MOD DC/DC 24V 50W |
相关代理商/技术参数 |
参数描述 |
|---|---|
| A5348CA-T | 功能描述:IC SMOKE DETECTOR ION 16-DIP RoHS:是 类别:集成电路 (IC) >> 接口 - 传感器和探测器接口 系列:- 其它有关文件:Automotive Product Guide 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:74 系列:- 类型:触控式传感器 输入类型:数字 输出类型:数字 接口:JTAG，串行 电流 - 电源:100µA 安装类型:表面贴装 封装/外壳:20-TSSOP（0.173"，4.40mm 宽） 供应商设备封装:20-TSSOP 包装:管件 |
| A5349CA | 制造商:ALLEGRO 制造商全称:Allegro MicroSystems 功能描述:AC SMOKE DETECTOR WITH INTERCONNECT AND TIMER |
| A53506 | 制造商:n/a 功能描述:Ships in 2 days |
| A5350CA | 功能描述:IC SMOKE DETECTOR ION 16-DIP RoHS:否 类别:集成电路 (IC) >> 接口 - 传感器和探测器接口 系列:- 其它有关文件:Automotive Product Guide 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:74 系列:- 类型:触控式传感器 输入类型:数字 输出类型:数字 接口:JTAG，串行 电流 - 电源:100µA 安装类型:表面贴装 封装/外壳:20-TSSOP（0.173"，4.40mm 宽） 供应商设备封装:20-TSSOP 包装:管件 |
| A5350CA-T | 功能描述:IC SMOKE DETECTOR ION 16-DIP RoHS:是 类别:集成电路 (IC) >> 接口 - 传感器和探测器接口 系列:- 其它有关文件:Automotive Product Guide 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:74 系列:- 类型:触控式传感器 输入类型:数字 输出类型:数字 接口:JTAG，串行 电流 - 电源:100µA 安装类型:表面贴装 封装/外壳:20-TSSOP（0.173"，4.40mm 宽） 供应商设备封装:20-TSSOP 包装:管件 |
发布紧急采购，3分钟左右您将得到回复。