MAX820REPE Maxim Integrated, MAX820REPE Datasheet - Page 10

• Manufacturer Part Number: MAX820REPE
• Description: Supervisory Circuits
• Manufacturer: Maxim Integrated
• Series: MAX792, MAX792L, MAX792M, MAX792R, MAX792S, MAX792T, MAX820, MAX820L, MAX820M, MAX820R, MAX820S, MAX820Tr

Specifications of MAX820REPE

• Number Of Voltages Monitored: 1
• Monitored Voltage: 2.75 V to 5.5 V
• Undervoltage Threshold: 2.55 V
• Overvoltage Threshold: 2.7 V
• Output Type: Active High, Active Low, Push-Pull
• Manual Reset: Resettable
• Watchdog: Watchdog
• Battery Backup Switching: No Backup
• Power-up Reset Delay (typ): 280 ms
• Supply Voltage - Max: 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• Package / Case: PDIP N
• Chip Enable Signals: Yes
• Maximum Power Dissipation: 842 mW
• Minimum Operating Temperature: - 40 C
• Power Fail Detection: Yes
• Supply Current (typ): 150 uA
• Supply Voltage - Min: 2.75 V

Microprocessor and Nonvolatile
Memory Supervisory Circuits
Figure 2. Manual-Reset Timing Diagram
Figure 3. Diode "OR" connections allow multiple reset sources
to connect to
In internal threshold mode, the low-line comparator
monitors V
above the reset threshold, and with 15mV of hysteresis.
For normal operation (V
LOWLINE is pulled to V
to the µP, as described in the previous section, when
V
The MAX792/MAX820 provide both RESET and RESET
outputs. The RESET and RESET outputs ensure that the
µP powers up in a known state, and prevent code-exe-
cution errors during power-up, power-down, or
brownout conditions.
The reset function will be asserted during the following
conditions:
10
CC
1) V
2) MR less than 1.30V typ.
3) Reset remains asserted for 200ms typ after V
begins to fall (Figure 4).
______________________________________________________________________________________
rises above the reset threshold or after MR has
exceeded 1.30V typ.
*
SOURCES
CC
DIODES NOT REQUIRED ON OPEN-DRAIN OUTPUTS
OTHER
RESET
CE IN OV
less than the programmed reset threshold.
CE OUT
CC
RESET
MR .
MR
with a threshold voltage typically 120mV
MANUAL RESET
CC
*
*
. Use LOWLINE to provide an NMI
CC
above the reset threshold),
.
.
.
9
MR
25µs MIN
12µs TYP
15µs TYP
Reset Function
Low-Line Output
MAX792
MAX820
CC
When reset is asserted, all the internal counters are
reset, the watchdog output (WDO) and watchdog-pulse
output (WDPO) are set high, and the set watchdog-time-
out input (SWT) is set to (V
connected to V
enable transmission gate is also disabled while reset is
asserted; the chip-enable input (CE IN) becomes high
impedance and the chip-enable output (CE OUT) is
pulled up to V
Figure 4a. Connection for Internal Threshold Mode
Figure 4b. Connection for External Threshold Programming Mode
R3 = 1.30V x V
R2 = 1.30V x V
R1 = V
V
V
LOW LINE
RESET
CC MAX
I
R3
R1
MAX
R2
x I
CC MAX
CC MAX
MAX
x I
– (R2 + R3)
4
5
MAX
CC
RESET IN/INT
LLIN/REFOUT
.
CC
–
RESET IN/INT
LLIN/REFOUT
R3
(for internal timeouts). The chip-
MAX792
MAX792
GND
V
I
V
MAX
CC
GND
V
IN
V
12
3
CC
IN
3
12
CC
= THE MAXIMUM DESIRED CURRENT
THROUGH THE VOLTAGE DIVIDED.
LOW LINE
LOW LINE
- 0.6V) if it is not already
RESET
RESET
RESET
RESET
2
1
10
1
2
10
TO µP
TO µP
TO µP NMI
TO µP
TO µP NMI
TO µP