DS3234
Extremely Accurate SPI Bus RTC
with Integrated Crystal and SRAM
Maxim Integrated | 3
www.maximintegrated.com
Electrical Characteristics (continued)
(V
CC
= 2.0V to 5.5V, V
CC
= active supply (see Table 1), T
A
= -40°C to +85°C, unless otherwise noted.) (Typical values are at
V
CC
=
3.3V, V
BAT
= 3.0V
, and T
A
= +25°C, unless otherwise noted. TCXO operation guaranteed from 2.3V to 5.5V on V
CC
and 2.3V to 3.8V on
V
BAT
.) (Notes 2, 3)
PARAMETER
S
YMBOL
CONDITION
S
MIN
TYP
MAX
UNIT
S
Logic 0 Output, 32kHz
V
OL
I
OL
= 1mA
0.4
V
Logic 1 Output, DOUT
V
OH
I
OH
= -1.0mA
0.85 x V
CC
V
Logic 0 Output, DOUT,
INT
/SQW
V
OL
I
OL
= 3mA
0.4
V
Logic 0 Output,
RST
V
OL
I
OL
= 1.0mA
0.4
V
Output Leakage Current 32kHz,
INT
/SQW, DOUT
I
LO
Output high impedance
-1
0
+1
µA
Input Leakage DIN,
CS
, SCLK
I
LI
-1
+1
µA
RST
Pin I/O Leakage
I
OL
RST
high impedance (Note 6)
-200
+10
µA
TCXO (V
CC
= 2.3V to 5.5V, V
BAT
= 2.3V to 3.8V, T
A
= -40
°
C to +85
°
C, unless otherwise noted.) (Notes 2 and 3)
Output Frequency
f
OUT
V
CC
= 3.3V or V
BAT
= 3.3V
32.768
kHz
0°C to +40°C
-2
+2
Frequency Stability vs.
Temperature
Δ
f/f
OUT
V
CC
= 3.3V or
V
BAT
= 3.3V
-40°C to 0°C and
+40°C to +85°C
-3.5
+3.5
ppm
Frequency Stability vs. Voltage
Δ
f/V
1
ppm/V
-40°C
0.7
+25°C
0.1
+70°C
0.4
Trim Register Frequency
Sensitivity per LSB
Δ
f/LSB
Specified at:
+85°C
0.8
ppm
Temperature Accuracy
Temp
-3
+3
°C
First year
±1.0
Crystal Aging
Δ
f/f
OUT
After reflow,
not production tested
0–10 years
±5.0
ppm
Electrical Characteristics
(
V
CC
= 0V, V
BAT
= 2.0V to 3.8V
, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
S
YMBOL
CONDITION
S
MIN
TYP
MAX
UNIT
S
V
BAT
= 3.4V
1.5
2.3
Timekeeping Battery Current
(Note 5)
I
BATT
EOSC
= 0, BBSQW = 0,
CRATE1 = CRATE0 = 0
V
BAT
= 3.8V
1.5
2.5
µA
Temperature Conversion Current
I
BATTC
EOSC
= 0, BBSQW = 0
400
µA
Data-Retention Current
I
BATTDR
EOSC
= 1
100
nA