CY14B256P_1106 Datasheet, PDF (3/36 Pages) Cypress Semiconductor – 256-Kbit (32 K x 8) Serial (SPI) nvSRAM with Real Time Clock

CY14B256P
Pinouts
Figure 1. Pin Diagram – 16-pin SOIC
NC 1
VRTCbat ₂
Xout ₃
Xin ₄
WP 5
HOLD 6
V_{RTCcap 7}
V_SS
8
16 V_CC
15 INT
14
Top View ₁₃
not to scale
12
V_CAP
SO
SI
11 ^SCK
10 CS
9 HSB
Table 1. Pin Definitions
Pin Name
CS
I/O Type
Input
SCK
Input
SI
SO
WP
HOLD
HSB
Input
Output
Input
Input
Input/output
V_CAP
Power supply
V_RTCcap
V_RTCbat
Xout
Xin
INT
NC
V_SS
V_CC
Power supply
Power supply
Output
Input
Output
No connect
Power supply
Power supply
Description
Chip select. Activates the device when pulled LOW. Driving this pin HIGH puts the device in low
power standby mode.
Serial clock. Runs at speeds up to maximum of f_SCK. Serial input is latched at the rising edge of
this clock. Serial output is driven at the falling edge of the clock.
Serial input. Pin for input of all SPI instructions and data.
Serial output. Pin for output of data through SPI.
Write protect. Implements hardware write protection in SPI.
HOLD pin. Suspends serial operation.
Hardware STORE busy:
Output: Indicates busy status of nvSRAM when LOW. After each hardware and software STORE
operation HSB is driven HIGH for a short time (t_HHHD) with standard output high current and then
a weak internal pull-up resistor keeps this pin HIGH (external pull-up resistor connection optional).
Input: Hardware STORE implemented by pulling this pin LOW externally.
AutoStore capacitor. Supplies power to the nvSRAM during power loss to STORE data from the
SRAM to nonvolatile elements. If AutoStore is not needed, this pin must be left as No Connect. It
must never be connected to ground.
Capacitor backup for RTC. Left unconnected if V_RTCbat is used.
Battery backup for RTC. Left unconnected if V_RTCcap is used.
Crystal output connection. Drives crystal on start up.
Crystal input connection. For 32.768 kHz crystal.
Interrupt output. Programmable to respond to the clock alarm, the watchdog timer, and the power
monitor. Also programmable to either active HIGH (push or pull) or LOW (open drain).
No connect. This pin is not connected to the die.
Ground
Power supply (2.7 V to 3.6 V)
Document Number: 001-53881 Rev. *F
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