Datasheet

(V
CC
= full operating range, V
BATT
= 2.8V, T
A
= +25°C, unless otherwise noted.)
Note 2: T
A
= full operating range
Note 3: WDI is guaranteed to be in the mid-level (inactive) state if WDI is floating and V
CC
is in the operating voltage range. WDI is
internally biased to 38% of V
CC
with an impedance of approximately 125kΩ.
PARAMETER CONDITIONS MIN TYP MAX UNITS
Watchdog Timeout Period,
External Clock
Long period 4032 4097
Clock
cycles
Short period 960 1025
Minimum WDI Input Pulse Width V
IL
= 0.4V, V
IH
= 3.5V, V
CC
= 5V 200 ns
RESET and RESET Output
Voltage (Note 2)
I
SINK
= 400µA, V
CC
= 2V, V
BATT
= 0V 0.4
VI
SINK
= 1.6mA, 3V < V
CC
< 5.5V 0.4
I
SOURCE
= 1µA, V
CC
= 5V 3.5
LOW LINE and WDO Output
Voltage
I
SINK
= 800µA, T
A
= full 0.4
V
I
SOURCE
= 1µA, V
CC
= 5V, T
A
= full 3.5
Output Short-Circuit Current RESET, RESET, WDO, LOW LINE 1 3 25 µA
WDI Input Threshold
V
CC
= 5V
(Note 3)
Logic-low 0.8
VLogic-high (MAX696) 3.5
Logic-high (MAX697) 3.8
WDI Input Current
V
WDI
= V
OUT
20 50
µA
V
WDI
= 0V -50 -15
POWER-FAIL DETECTOR
PFI Input Threshold V
CC
= 3V, 5V 1.2 1.3 1.4 V
PFI - LL
IN
Threshold Difference V
CC
= 3V, 5V ±15 ±50 mV
PFI Input Current ±0.01 ±25 nA
LL
IN
Input Current
MAX697 -25 ±0.01 +25
nA
MAX696 -500 ±0.01 +25
PFO Output Voltage
I
SINK
= 1.6mA 0.4
V
I
SOURCE
= 1µA, V
CC
= 5V 3.5
PFO Short-Circuit Source Current V
PFI
= 0V, V
PFO
= 0V 1 3 25 µA
CHIP-ENABLE GATING (MAX697)
CE IN Thresholds
V
IL
0.8
V
V
IH
, V
CC
= 5V 3.0
CE IN Pullup Current 3 µA
CE OUT Output Voltage
I
SINK
= 1.6mA 0.4
VI
SOURCE
= 800µA V
CC
- 0.5V
I
SOURCE
= 1µA, V
CC
= 0V V
CC
- 0.05V
CE Propagation Delay V
CC
= 5V 80 150 ns
OSCILLATOR
OSC IN Input Current ±2 µA
OSC SEL Input Pullup Current 5 µA
OSC IN Frequency Range V
OSC SEL
= 0V 0 250 kHz
OSC IN Frequency with External
Capacitor
V
OSC SEL
= 0V, C
OSC
= 47pF 4 kHz
MAX696/MAX697 Microprocessor Supervisory Circuits
www.maximintegrated.com
Maxim Integrated │ 3
Electrical Characteristics (continued)