SM5837AF Datasheet, PDF (7/8 Pages) Nippon Precision Circuits Inc – Variable-length 1H Delay Line LSI

SM5837AF
Table 1. Delay bit length setting
DL10 DL9
DL8
DL7
DL6
DL5
DL4
DL3
DL2
DL1
DL0
Delay length
0
0
1
1
1
1
0
0
0
1
0
513
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
0
1
1
1
1
1
0
0
0
0
1
1024
0
1
1
1
1
1
0
0
0
1
0
1025
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
1
1
1
1
1
1
0
0
0
0
1
2048
1
1
1
1
1
1
0
0
0
1
0
2049
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
↓
1
1
1
1
1
1
1
1
1
1
0
2077
1
1
1
1
1
1
1
1
1
1
1
2078
Serial Input Set Method
(PARA, SDI, SICK, LEN)
When PARA goes LOW, 3-input serial data set
method is used to set the delay length. Inputs DL3 to
DL10 are ignored. SDI, SICK and LEN function as
the serial data input, serial data shift clock and latch
clock enable, respectively.
The serial input data format, shown in figure XREF,
comprises 11-bit serial data (S0 to S10) input on SDI
in sync with SICK. The data on SDI is clocked into
the serial-to-parallel converter shift register on the
rising edge of SICK, and 11-bit parallel data is then
latched into the delay length set register on the rising
edge of LEN.
The delay length (L_H) is determined by the input
data S0 to S10 (just as for parallel input data DL0 to
DL10) as shown in equation 2. See also table 1.
Note that SICK and CLK can be asynchronous.
10
L_H = 31 + _∑ {Sk × 2^k}
(2)
k=0
SDI
S10 S9 S8 S7 S6 S5 S4 S3 S2 S1 S0
SICK
LEN
Dotted lines indicate possible SICK and LEN states.
Figure 1. Serial input data format
Delay Clock Input (CLK)
All 1H delay registers operate in sync with the delay
clock CLK. The maximum clock frequency is 40
MHz.
Input Data (DI0 to DI11)
DI0 to DI11 are the 12-bit data inputs.
Output Data (DO0 to DO11,OE)
DO0 to DO11 are the 12-bit data outputs. They are
tristate outputs, with the output state selected by OE.
When OE is HIGH, the outputs are enabled. When
OE is LOW, the outputs are disabled (high-imped-
ance state).
Reset (RSTN)
At power-ON, the internal timing generator circuits
must be initialized by a LOW-level input on RSTN.
After RSTN goes HIGH, the set delay length
becomes active.
NIPPON PRECISION CIRCUITS—7