ade7518 Analog Devices, Inc., ade7518 Datasheet - Page 9

• Manufacturer Part Number: ade7518
• Description: Single-phase Energy Measurement Ic With 8052 Mcu, Rtc, And Lcd Driver
• Manufacturer: Analog Devices, Inc.

TIMING SPECIFICATIONS
AC inputs during testing were driven at V
and 0.45 V for Logic 0. Timing measurements were made at V
minimum for Logic 1 and V
Figure 2.
Table 4. Clock Input (External Clock Driven XTAL1) Parameters
Parameter
t
t
t
t
t
1/t
1
Table 5. I
Parameter
t
t
t
t
t
t
t
t
t
t
t
1
CK
CKL
CKH
CKR
CKF
BUF
L
H
SHD
DSU
DHD
RSU
PSU
R
F
SUP
The ADE7518 internal PLL locks onto a multiple (512 times) of the 32.768 kHz external crystal frequency to provide a stable 4.096 MHz internal clock for the system.
Input filtering on both the SCLK and SDATA inputs suppresses noise spikes of less than 50 ns.
The core can operate at this frequency or at a binary submultiple defined by the CD[2:0] bits, selected via the POWCON SFR (see Table 24).
CORE
1
2
SDATA (I/O)
C-Compatible Interface Timing Parameters (400 kHz)
SCLK (I)
V
t
PSU
SWOUT
Description
Bus-free time between stop condition and start condition
SCLK low pulse width
SCLK high pulse width
Start condition hold time
Data setup time
Data hold time
Setup time for repeated start
Stop condition setup time
Rise time of both SCLK and SDATA
Fall time of both SCLK and SDATA
Pulse width of spike suppressed
CONDITION
– 0.5V
0.45V
STOP
Description
XTAL1 period
XTAL1 width low
XTAL1 width high
XTAL1 rise time
XTAL1 fall time
Core clock frequency
PS
IL
maximum for Logic 0, as shown in
t
BUF
CONDITION
START
t
DSU
0.2V
0.2V
SWOUT
TEST POINTS
t
SHD
SWOUT
SWOUT
− 0.5 V for Logic 1
1
MSB
– 0.1V
1
+ 0.9V
Figure 2. Timing Waveform Characteristics
Figure 3. I
t
DHD
2 TO 7
IH
2
C-Compatible Interface Timing
Rev. 0 | Page 9 of 128
t
L
V
LOAD
Min
0.032768
LSB
V
V
8
LOAD
LOAD
t
t
SUP
SUP
For timing purposes, a port pin is no longer floating when a
100 mV change from load voltage occurs. A port pin begins to
float when a 100 mV change from the loaded V
occurs, as shown in Figure 2.
For Table 4 to Table 9, C
3.6 V, and all specifications T
– 0.1V
+ 0.1V
t
H
t
DSU
32.768 kHz External Crystal
ACK
REFERENCE
9
POINTS
TIMING
t
RSU
Typ
30.52
6.26
6.26
9
9
1.024
t
DHD
LOAD
REPEATED
START
S(R)
MIN
= 80 pF for all outputs, V
to T
V
V
LOAD
LOAD
MAX
– 0.1V
– 0.1V
Max
4.096
, unless otherwise noted.
t
F
MSB
t
V
Typ
1.3
1.36
1.14
251.35
740
400
12.5
400
200
300
50
F
LOAD
1
t
R
t
R
OH
/V
ADE7518
DD
OL
Unit
μs
μs
μs
ns
ns
MHz
= 2.7 V to
level
Unit
μs
μs
μs
μs
ns
ns
ns
ns
ns
ns
ns