Datasheet

4-Pin, Ultra-Low-Voltage, Low-Power
µP Reset Circuits with Manual Reset
_______________________________________________________________________________________ 5
MAX6335/MAX6336/MAX6337
V
CC
GND
MAX6336
RESETMR
100k
(a)
V
CC
GND
MAX6335
RESET
100k*
(b)
*ASSUMES HIGH-Z RESET INPUT TO THE µP
MR
* Factory-trimmed reset thresholds are available in approximately
100mV increments, with a ±1.8% room-temperature variance.
T
A
= +25°C T
A
= -40°C to +125°C
MIN TYP MAX MIN MAX
MAX633_US25D_ 2.46 2.50 2.55 2.43 2.58
MAX633_US24D_ 2.36 2.40 2.44 2.33 2.47
MAX633_US23D_ 2.26 2.30 2.34 2.23 2.37
MAX633_US22D_ 2.16 2.20 2.24 2.13 2.27
MAX633_US21D_ 2.06 2.10 2.14 2.04 2.16
MAX633_US20D_ 1.96 2.00 2.04 1.94 2.06
MAX633_US19D_ 1.87 1.90 1.93 1.84 1.96
MAX633_US18D_ 1.77 1.80 1.83 1.75 1.85
MAX633_US17D_ 1.67 1.70 1.73 1.65 1.75
MAX633_US16D_ 1.57 1.60 1.63 1.55 1.65
RESET
THRESHOLD
SUFFIX
Table 1. Factory-Trimmed Reset
Thresholds*
Figure 2. Ensuring Reset Valid down to V
CC
= 0
(Figure 2a). The pull-down resistor value is not critical;
100kΩ is large enough not to load RESET, and small
enough to pull it low. For the MAX6335, where RESET
must be valid to V
CC
= 0, a 100kΩ pull-up resistor
between RESET and V
CC
will hold RESET high when
V
CC
falls below 0.7V (Figure 2b).
Since the MAX6337 has an open-drain, active-low out-
put, it typically uses a pull-up resistor. With this device,
RESET will most likely not maintain an active condition,
but will drift to a non-active level due to the pull-up
resistor and the reduced sinking capability of the open-
drain device. Therefore, this device is not recommend-
ed for applications where the RESET pin is required to
be valid down to V
CC
= 0.