|
|
PDF MB3793-30 Data sheet ( Hoja de datos )
| Número de pieza | MB3793-30 | |
| Descripción | POWER-VOLTAGE MONITORING IC | |
| Fabricantes | Fujitsu Media Devices | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MB3793-30 (archivo pdf) en la parte inferior de esta página. Total 20 Páginas | ||
|
No Preview Available !
FUJITSU SEMICONDUCTOR
DATA SHEET
To Top / Lineup / Index
DS04-27402-2E
ASSP
POWER-VOLTAGE MONITORING
IC WITH WATCHDOG TIMER
MB3793-42/30
DESCRIPTION
The MB3793 is an integrated circuit to monitor power voltage; it incorporates a watchdog
timer.
A reset signal is output when the power is cut or falls abruptly. When the power recovers
normally after resetting, a power-on reset signal is output to microprocessor units (MPUs).
An internal watchdog timer with two inputs for system operation diagnosis can provide a
fail-safe function for various application systems.
Two models with detection voltages of 4.2 and 3.0 V are available. There is also a mask
option that can detect voltages of 4.9 to 3.0 V in 0.1-V steps.
The model numbers are MB3793-42 or -30 corresponding to the detected voltage. The
model number and package code are as shown below.
Model No.
MB3793-42
MB3793-30
Package code
3793-A
3793-N
Detection voltage
4.2 V
3.0 V
FEATURES
• Precise detection of power voltage fall: ±2.5%
• Detection voltage with hysteresis
• Low power dispersion: ICC = 27 µA (reference)
• Internal dual-input watchdog timer
• Watchdog-timer halt function (by inhibition pin)
• Independently-set watchdog and reset times
• Mask option for detection voltage (4.9 to 3.0 V, 0.1-V steps)
8-PIN PLASTIC DIP
(DIP-8P-M01)
8-PIN PLASTIC SOL
(FPT-8P-M02)
This device contains circuitry to protect the inputs against
damage due to high static voltages or electric fields. However,
it is advised that normal precautions be taken to avoid
application of any voltage higher than maximum rated voltages
to this high impedance circuit.
1
1 page  
s STANDARD CONNECTION
VCC
To Top / Lineup / Index
MB3793-42/30
CTW
CTP
CTW
VCC
RESET
CTP
MB3793
CK1
INH GND
CK2
RESET VCC
Microprocessor 1
CK
GND
RESET VCC
Microprocessor 2
CK
GND
Equation of time-setting capacitances (CTP and CTW) and set time
tPR (ms) ≈ A x CTP (µF)
tWD (ms) ≈ B x CTW (µF) + C x CTP (µF)
However, when —CT—P ≤ about 10,
CTW
tWD (ms) ≈ B x CTW (µF)
tWR (ms) ≈ D x CTP (µF)
Model No.
MB3793-42
MB3793-30
A
1300
750
Values of A, B, C, and D
BCD
1500
3
100
1600
4
55
Remark
(Example) When CTP = 0.1 µF and CTW = 0.01 µF,
• MB3793-42
tPR ≈ 130 [ms]
tWD ≈ 15 [ms]
tWR ≈ 10 [ms]
• MB3793-30
tPR ≈ 75 [ms]
tWD ≈ 16 [ms]
tWR ≈ 5.5 [ms]
5
5 Page 
To Top / Lineup / Index
MB3793-42/30
(7) When the voltage of the CTP pin exceeds Vth again as a result of recharging CTP, resetting is canceled and the watchdog timer restarts
monitoring.
The watchdog timer reset time (tWR) can be calculated by the following equation.
tWR (ms) ≈ D x CTP (µF)
Where, D is about 100 in the MB3793-42 and 55 in the MB3793-30.
(8) When VCC falls below the rising-edge detection voltage (VSL), the voltage of the CTP pin falls and a reset signal is output, and the
voltage at the RESET pin changes to Low level. VSL is about 4.2 V in the MB3793-42 and 3.0 V in the MB3793-30.
(9) When VCC exceeds VSH, CTP begins charging.
(10) When the voltage of the CTP pin exceeds Vth, resetting is canceled and the watchdog timer restarts.
(11) When an inhibition signal is input (INH pin is High level), the watchdog timer is halted forcibly.
In this case, VCC monitoring is continued ((8) - (9)) without the watchdog timer.
The watchdog timer does not function unless this inhibition input is canceled.
(12) When the inhibition input is canceled (INH pin is Low level), the watchdog timer restarts.
(13) When the VCC voltage falls below VSL after power-off, a reset signal is output.
Similar operation is also performed for negative clock-pulse input (Timing Chart 2).
Short-circuit the clock pins CK1 and CK2 to monitor a single clock. The basic operation is the same but the clock pulses are monitored at every
other pulse (Timing Chart 3).
s ABSOLUTE MAXIMUM RATINGS
Parameter
Power voltage*
CK1
Input voltage
CK2
INH
Reset output voltage
(direct current)
RESET
Allowable loss (Ta ≤ +85°C)
Storage temperature
Symbol
VCC
VCK1
VCK2
VINH
IOL
IOH
PD
Tstg
LImits
-0.3 to +7
-0.3 to +7
-10 to +10
200
-55 to +125
(Ta = +25°C)
Symbo
V
V
mA
mW
°C
*The power voltage is based on the ground voltage (0 V).
Note: Permanent device damage may occur if the above ABSOLUTE MAXIMUM RATINGS are exceeded. Functional operation should be
restricted to the conditions as detailed in the operational sections of this data sheet. Exposure to absolute maximum rating conditions
for extended periods may affect device reliability.
s RECOMMENDED OPERATING CONDITIONS
Parameter
Reset (RESET) output current
Power-on reset hold time setting capacity
Watchdog-timer monitoring time setting capacity
Watchdog timer monitoring time
Operating ambient temperature
Symbol
IOL
IOH
CTP
CTW
tWD
Ta
Min.
-5
0.001
0.001
0.1
-40
Limits
Typical
-
-
-
-
-
Max.
+5
10
1
1500
+85
Unit
mA
µF
µF
ms
°C
Note: These recommended operation conditions guarantee normal logic operation of an LSI circuit. The limits of the AC and DC electrical
characteristics are guaranteed within these recommended conditions.
11
11 Page | ||
| Páginas | Total 20 Páginas | |
| PDF Descargar | [ Datasheet MB3793-30.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MB3793-30 | POWER-VOLTAGE MONITORING IC | Fujitsu Media Devices |
| MB3793-30A | POWER-VOLTAGE MONITORING IC WITH WATCHDOG TIMER | Fujitsu Media Devices |
| MB3793-37A | POWER-VOLTAGE MONITORING IC WITH WATCHDOG TIMER | Fujitsu Media Devices |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |