MAX709TC/D Maxim Integrated, MAX709TC/D Datasheet - Page 4

• Manufacturer Part Number: MAX709TC/D
• Description: Supervisory Circuits
• Manufacturer: Maxim Integrated
• Series: MAX709L, MAX709M, MAX709R, MAX709S, MAX709Tr

Specifications of MAX709TC/D

• Number Of Voltages Monitored: 1
• Monitored Voltage: 3 V, 3.3 V, 5 V
• Undervoltage Threshold: 3 V
• Overvoltage Threshold: 3.15 V
• Output Type: Active Low, Push-Pull
• Manual Reset: Not Resettable
• Watchdog: No Watchdog
• Battery Backup Switching: No Backup
• Power-up Reset Delay (typ): 560 ms
• Supply Voltage - Max: 5.5 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Package / Case: Die
• Chip Enable Signals: No
• Minimum Operating Temperature: 0 C
• Power Fail Detection: No
• Supply Current (typ): 150 uA
• Supply Voltage - Min: 1 V

Power-Supply Monitor with Reset
In addition to issuing a reset to the microprocessor
(µP) during power-up, power-down, and brownout con-
ditions, the MAX709 is relatively immune to short dura-
tion negative-going V
Figure 1 shows typical transient duration vs. reset com-
parator overdrive, for which the MAX709 does not gen-
erate a reset pulse. The graph was generated using a
negative-going pulse applied to V
above the actual reset threshold and ending below it
by the magnitude indicated (reset comparator over-
drive). The graph indicates the typical maximum pulse
width that a negative-going V
without causing a reset pulse to be issued. As the
magnitude of the transient increases (goes farther
below the reset threshold), the maximum allowable
pulse width decreases.
MAX709L/MAX709M, a V
below the reset threshold and lasts 40µs or less will not
cause a reset pulse to be issued.
4
__________Applications Information
____________________Pin Description
1, 4, 5,
PIN
6, 8
_______________________________________________________________________________________
2
3
7
Negative-Going V
RESET
NAME
GND
N.C.
V
CC
No Connect. There is no internal
connection to this pin.
+5V, +3.3V, or +3V Supply Voltage
Ground
Reset Output remains low while V
below the reset threshold, and for
280ms after V
threshold.
CC
transients (glitches).
CC
transient that goes 100mV
CC
FUNCTION
CC
Typically, for the
transient may have
rises above the reset
CC
CC
Transients
, starting 1.5V
CC
is
Figure 1. Maximum Transient Duration without Causing a
A 0.1µF bypass capacitor mounted as close as possible
to pin 2 (V
When V
no longer sinks current—it becomes an open circuit.
Therefore, high-impedance CMOS logic inputs con-
nected to the RESET output can drift to undermined
voltages. This presents no problem in most applica-
tions, since most µP and other circuitry is inoperative
with V
RESET output must be valid down to 0V, adding a pull-
down resistor to the RESET pin will cause any stray
leakage currents to flow to ground, holding RESET low
(see Figure 2). The resistance value of R1 is not criti-
cal. It should be about 100k , which is large enough
not to load RESET and small enough to pull RESET to
ground.
CC
CC
Reset Pulse vs. Reset Comparator Overdrive
below 1V. However, in applications where the
150
100
CC
50
Ensuring a Valid RESET Output
0
falls below 1V, the MAX709 RESET output
RESET COMPARATOR OVERDRIVE, V
) provides additional transient immunity.
10
MAX709R/S/T
MAX709L/M
100
Down to V
1k
T
A
TH
= +25°C
- V
10ns
CC
10k
(mV)
CC
= 0V