CY7C1416BV18, CY7C1427BV18
CY7C1418BV18, CY7C1420BV18
Document Number: 001-07033 Rev. *C
Page 7 of 29
CQ
Output Clock CQ Referenced with Respect to C. This is a free-running clock and is synchronized to the input clock
for output data (C) of the DDR-II. In the single clock mode, CQ is generated with respect to K. The timing
for the echo clocks is shown in the Switching Characteristics on page 23.
CQ
Output Clock CQ Referenced with Respect to C. This is a free-running clock and is synchronized to the input clock
for output data (C) of the DDR-II. In the single clock mode, CQ is generated with respect to K. The timing
for the echo clocks is shown in the Switching Characteristics on page 23.
ZQ
Input
Output Impedance Matching Input. This input is used to tune the device outputs to the system data bus
impedance. CQ, CQ, and Q[x:0] output impedance are set to 0.2 x RQ, where RQ is a resistor connected
between ZQ and ground. Alternatively, connect this pin directly to VDDQ, which enables the minimum
impedance mode. This pin cannot be connected directly to GND or left unconnected.
DOFF
Input
DLL Turn Off
− Active LOW. Connecting this pin to ground turns off the DLL inside the device. The timing
in the DLL turned off operation differs from those listed in this data sheet. For normal operation, this pin
must be pulled HIGH through 10 K
Ω or less pull up resistor. The device behaves in DDR-I mode when
the DLL is turned off. In this mode, operate the device at a frequency of up to 167 MHz with DDR-I timing.
TDO
Output
TDO for JTAG.
TCK
Input
TCK Pin for JTAG.
TDI
Input
TDI Pin for JTAG.
TMS
Input
TMS Pin for JTAG.
NC
N/A
Not Connected to the Die. Tie to any voltage level.
NC/72M
N/A
Not Connected to the Die. Tie to any voltage level.
NC/144M
N/A
Not Connected to the Die. Tie to any voltage level.
NC/288M
N/A
Not Connected to the Die. Tie to any voltage level.
VREF
Input-
Reference
Reference Voltage Input. Static input used to set the reference level for HSTL inputs, outputs, and AC
measurement points.
VDD
Power Supply Power Supply Inputs to the Core of the Device.
VSS
Ground
Ground for the Device.
VDDQ
Power Supply Power Supply Inputs for the Outputs of the Device.
Pin Definitions (continued)
Pin Name
IO
Pin Description
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