Datasheet

CY8C21634, CY8C21534, CY8C21434
CY8C21334, CY8C21234
Document Number: 38-12025 Rev. AB Page 49 of 53
CY8C21234 Errata Summary
The following table defines the errata applicability to available CY8C21234 family devices. An "X" indicates that the errata pertains to
the selected device.
Note Errata items, in the table below, are hyperlinked. Click on any item entry to jump to its description.
1. Internal Main Oscillator (IMO) Tolerance Deviation at Temperature Extremes
■ Problem Definition
Asynchronous Digital Communications Interfaces may fail framing beyond 0 °C to 70 °C. This problem does not affect
end-product usage between 0 °C and 70 °C.
■ Parameters Affected
The IMO frequency tolerance. The worst case deviation when operated below 0 °C and above +70 °C and within the upper
and lower datasheet temperature range is ±5%.
■ Trigger Condition(S)
The asynchronous Rx/Tx clock source IMO frequency tolerance may deviate beyond the datasheet limit of ±2.5% when
operated beyond the temperature range of 0 °C to +70 °C.
■ Scope of Impact
This problem may affect UART, IrDA, and FSK implementations.
■ Workaround
Implement a quartz crystal stabilized clock source on at least one end of the asynchronous digital communications interface.
■ Fix Status
No fix is currently planned.
2. I
2
C Errors
■ Problem Definition
The I
2
C block exhibits occasional data and bus corruption errors when the I
2
C master initiates transactions while the device is
transitioning in to or out of sleep mode.
■ Parameters Affected
Affects reliability of I
2
C communication to device, between I
2
C master, and third party I
2
C slaves.
■ Trigger Condition(S)
Triggered by transitions into and out of the device's sleep mode.
■ Scope of Impact
This problem may affect UART, IrDA, and FSK implementations.
■ Workaround
Firmware workarounds are available in firmware. Generally the workaround consists of disconnecting the I
2
C block from the
bus prior to going to sleep modes. I
2
C transactions during sleep are supported by a protocol in which the master wakes the
device prior to the I
2
C transaction
■ Fix Status
Will not be fixed.
Items Part Number Silicon Revision Fix Status
[1.]. Internal Main Oscillator (IMO)
Tolerance Deviation at Temperature
Extremes
CY8C21234 A No fix is currently planned.
[2]. I2C Errors CY8C21234 A No fix is currently planned.