- 您现在的位置：买卖IC网 > PDF目录15381 > ADM805LARNZ-REEL (Analog Devices Inc)IC SUPERVISOR MPU 4.65V WD 8SOIC PDF资料下载
参数资料
| 型号： | ADM805LARNZ-REEL |
| 厂商： | Analog Devices Inc |
| 文件页数： | 7/8页 |
| 文件大小： | 0K |
| 描述： | IC SUPERVISOR MPU 4.65V WD 8SOIC |
| 标准包装： | 2,500 |
| 类型： | 备用电池电路 |
| 监视电压数目： | 1 |
| 输出： | 推挽式，图腾柱 |
| 复位： | 高有效 |
| 复位超时： | 最小为 140 ms |
| 电压 - 阀值： | 4.65V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 8-SOIC（0.154"，3.90mm 宽） |
| 供应商设备封装： | 8-SOIC |
| 包装： | 带卷 (TR) |
ADM690A/ADM692A/ADM802L/M/ADM805L/M
If the watchdog timer is not needed, the WDI input should be
left floating.
The Power Fail Input, PFI, monitors the input power supply via
a resistive divider network. The voltage on the PFI input is
compared with a precision 1.25 V internal reference. If the input
voltage drops below 1.25 V, a power fail output ( PFO ) signal is
generated. This warns of an impending power failure and may
be used to interrupt the processor so that the system may be
shut down in an orderly fashion. The resistors in the sensing
network are ratioed to give the desired power fail threshold
voltage V T .
V T = (1.25 R 1/ R 2) + 1.25 V
R 1/ R 2 = ( V T /1.25) – 1
Alternate Watchdog Input Drive Circuits
The watchdog feature can be enabled and disabled under
program control by driving WDI with a 3-state buffer. When
three-stated, the WDI input will float thereby disabling the
watchdog timer.
Operation Without a Backup Supply
If a backup power source is not used, V BATT should be con-
nected to GND and V OUT should be connected to V CC .
Replacing the Backup Battery
The backup battery may be replaced without any danger of
spurious resetting when V CC is present. Since V CC is above the
reset threshold, a reset will not occur even if V BATT is floating
while a replacement battery is being inserted. This differs from
older generation products where leakage currents flowing out
V BATT could cause spurious resetting during battery replacement.
Ps With Bidirectional RESET
In order to prevent contention for microprocessors with a
bidirectional reset line, a current limiting resistor should be
inserted between the ADM69xA/ADM80xx RESET output pin
and the μ P reset pin. This will limit the current to a safe level if
there are conflicting output reset levels. A suitable resistor value
is 4.7 k ? . If the reset output is required for other uses, then it
should be buffered as shown in Figure 13.
High Capacity Backup Capacitors
High capacity (0.1 μ F or greater) capacitors may be used as a
backup power source. A typical application is shown in Fig-
ure 12.
+5V
+5V
V CC
ADM690A
ADM692A
ADM802L
ADM802M
BUFFERED
RESET
μP
V CC
V BATT
V OUT
RESET
RESET *
TO STATIC RAM
TO μP
RESET
GND
RESET
GND
0.1F
+
GND
Figure 13. Bidirectional Reset
* FOR ADM805L/ADM805M ONLY
Figure 12. High Capacity Capacitor
REV. 0
–7 –
相关PDF资料 |
PDF描述 |
|---|---|
| H2BBT-10103-W8-ND | JUMPER-H1500TR/A3048W/H1500TR 3" |
| UPB2D101MHD1TN | CAP ALUM 100UF 200V 20% RADIAL |
| H2BBT-10103-V8-ND | JUMPER-H1500TR/A3048V/H1500TR 3" |
| GBC61DCMD-S288 | CONN EDGECARD 122POS .100 EXTEND |
| EBC61DCMI-S288 | CONN EDGECARD 122POS .100 EXTEND |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ADM805LM | 制造商:AD 制造商全称:Analog Devices 功能描述:Microprocessor Supervisory Circuits |
| ADM805M | 制造商:AD 制造商全称:Analog Devices 功能描述:Microprocessor Supervisory Circuits |
| ADM805MAN | 制造商:Analog Devices 功能描述:Processor Supervisor 4.4V 4.4V 8-Pin PDIP 制造商:Analog Devices 功能描述:PROCESSOR SUPERVISOR 4.4V 100UA 8PDIP - Rail/Tube |
| ADM805MARN | 制造商:AD 制造商全称:Analog Devices 功能描述:Microprocessor Supervisory Circuits |
| ADM809 | 制造商:AD 制造商全称:Analog Devices 功能描述:Microprocessor Supervisory Circuit in 3-Pin SOT-23 |
发布紧急采购，3分钟左右您将得到回复。