DS17287 Maxim, DS17287 Datasheet - Page 6

• Manufacturer Part Number: DS17287
• Description: The DS17285, DS17485, DS17885, DS17287, DS17487, and DS17887 real-time clocks (RTCs) are designed to be successors to the industry-standard DS12885 and DS12887
• Manufacturer: Maxim

CAPACITANCE
(T
AC TEST CONDITIONS
Real-Time Clocks
POWER-UP/POWER-DOWN CHARACTERISTICS
(T
DATA RETENTION (DS17x87 ONLY)
(T
WARNING: Negative undershoots below -0.3V while the part is in battery-backed mode can cause loss of
data.
6
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
Note 9:
Note 10: Guaranteed by design. Not production tested.
Expected Data Retention
Input Pulse Levels:
Output Load Including Scope and Jig:
Input and Output Timing Measurement Reference Levels:
Input Pulse Rise and Fall Times:
Recovery at Power-Up
V
V
V
V
Capacitance on All Input Pins
Except X1
Capacitance on IRQ, SQW, and
DQ0–DQ7 Pins
A
A
A
CC
PF(MIN)
CC
PF(MIN)
= +25°C) (Note 10)
= -40°C to +85°C) (Note 2)
= +25°C)
_____________________________________________________________________
Fall Time, V
Fall Time, V
PARAMETER
RTC modules can be successfully processed through conventional wave-soldering techniques as long as temperature
exposure to the lithium energy source contained within does not exceed +85°C. However, post-solder cleaning with water-
washing techniques is acceptable, provided that ultrasonic vibrations not used to prevent damage to the crystal.
Limits at -40°C are guaranteed by design and not production tested.
All voltages are referenced to ground.
All outputs are open.
Specified with CS = RD = WR = V
Applies to the AD0–AD7 pins, IRQ, and SQW when each is in a high-impedance state.
Measured with a 32.768kHz crystal attached to X1 and X2.
Measured with a 50pF capacitance load plus 1TTL gate.
If the oscillator is disabled in software, or if the countdown chain is in reset, t
immediately accessible.
PARAMETER
PARAMETER
PF(MAX)
PF(MAX)
to
to
PARAMETER
SYMBOL
SYMBOL
SYMBOL
t
t
C
C
REC
DR
t
t
F
R
IN
IO
CC
, ALE, AD0–AD7 = 0.
(Note 9)
(Note 9)
(Note 10)
(Note 10)
CONDITIONS
CONDITIONS
CONDITIONS
0 to 3.0V
50pF + 1TTL Gate
Input/Output: V
5ns
IL
max and V
REC
CONDITIONS
IH
is bypassed, and the part becomes
MIN
MIN
MIN
300
min
10
20
0
TYP
TYP
TYP
MAX
MAX
MAX
150
12
12
UNITS
UNITS
Years
UNITS
ms
µs
µs
pF
pF