SAF-C164SM Infineon Technologies, SAF-C164SM Datasheet - Page 142

• Manufacturer Part Number: SAF-C164SM
• Description: 16-Bit CMOS Microcontroller
• Manufacturer: Infineon Technologies

Port Driver Temperature Compensation
The temperature compensation for the port drivers provides driver output characteristics
which are stable (within a certain band of parameter variation) over the specified
temperature range, e.g. -40 C … +125 C. The drive capability of the output drivers is
reduced when the temperature is not in the upper range to improve the EME behavior.
The temperature compensation is based on a reference clock signal which is derived
from the CPU clock by a programmable divider (see
Figure 7-3
The clock divider is programmed via bitfield TCDIV in register PTCR. TCDIV can be
calculated using the following formula:
TCDIV = Integer ((
Example for
TCDIV = Integer ((25
Generally, temperature compensation is a transparent feature. The Port Temperature
Compensation Register PTCR provides access to the actual compensation value and
even allows software control of this mechanism.
This is useful in two cases:
• Device testing: the function of the compensation mechanism can be verified during
• User control: during operation the device can be controlled via externally provided
Temperature compensation is initialized using register PTCR (enable and prescaler
for reference clock).
The reference clock is used to generate a temperature-related count value which is
compared to three thresholds (temperature levels) at which the four control values (max,
high, low, min) are switched.
User’s Manual
production testing or characterization.
compensation values rather than via the internal mechanism.
f
f
CPU
CPU
Temperature Compensation Clock Generation
= 25 MHz:
f
CPU
6.7) - 2) = 165 (= A5
6.7) - 2) [
f
CPU
Prog. Divider
N = (TCDIV+1)
in MHz]
N:1
7-7
H
).
Figure
7-3).
Reference Clock
C164CM/C164SM
f
REF
MCB05124
Parallel Ports
Derivatives
V1.0, 2002-02