
STD130
5-206
Samsung ASIC
DPSRAMBW_LP
Low-Power Dual-Port Synchronous Static RAM with Bit-Write
Pin Descriptions
Pin Capacitance
(Unit = SL)
NOTE:
Each pin’s capacitance is exactly same regardless of available mux types.
Name
CK1
CK2
Type
Description
Clock
Clock input. CSN, WEN, A[] and DI[] are latched into the RAM on the rising
edge of CK. If CSN and WEN are low on the rising edge of CK, the RAM is in
write mode. If WEN is high on the rising edge of CK, the RAM is in read
mode. Upon the falling edge of CK, the RAM is in a precharge state.
Chip Enable input. The chip enable is active-low and is latched into the RAM
on the rising edge of CK. When CSN is low, the RAM is enabled for reading
or writing, depending on the state of WEN. When CSN is high, the RAM goes
to the standby mode and is disabled for reading or writing. DOUT remains
previous data output.
Read or write enable input. The read/write enable is latched into the RAM on
the rising edge of CK. When WEN is low, data are written to the addressed
location and DOUT remains stable. When WEN is high, data from the
addressed word are present at DOUT.
Bit-write enable input bus. The bit-write enable is latched into the RAM on the
rising edge of CK. Each bit of BWEN[] enables/disables the write operation of
corresponding data bit. BWEN[i] corresponds to DI[i] in bit-write. If WEN and
BWEN[0] are low and BWEN[1] is high, DI[0] is written into the memory
location specified on A[], but DI[1] is not written.
Data output enable input. The data output enable is asynchronously operated
regardless of the state of other inputs. When OEN is high, DOUT is disabled
and goes to high-impedance state.
Address input bus. The address is latched into the RAM on the rising edge of
CK.
CSN1
CSN2
Chip
Enable
WEN1
WEN2
Read/Write
Enable
BWEN1 [ ]
BWEN2 [ ]
Bit-Write
Enable
OEN1
OEN2
Data
Output
Enable
Address
A1 [ ]
A2 [ ]
DI1 [ ]
DI2 [ ]
DOUT1 [ ]
DOUT2 [ ]
Data Input
Data input bus. Data are latched on the rising edge of CK. Data input is
written into the addressed location in write mode.
Data
Output
Data output bus. Data output is valid after the rising edge of CK while the
RAM is in read mode. Data output remains previous data output while the
RAM is in write mode.
CK
13.70
CSN
3.43
WEN
3.39
BWEN
3.49
OEN
4.57
A
DI
3.39
DOUT
7.47
3.39