Z8F042AHJ020SC00TR Zilog, Z8F042AHJ020SC00TR Datasheet - Page 150

• Manufacturer Part Number: Z8F042AHJ020SC00TR
• Description: IC ENCORE XP MCU FLASH 4K 28SSOP
• Manufacturer: Zilog
• Series: Encore!® XP®r

Specifications of Z8F042AHJ020SC00TR

• Core Processor: Z8
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: IrDA, UART/USART
• Peripherals: Brown-out Detect/Reset, LED, LVD, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 23
• Program Memory Size: 4KB (4K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-SSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: Z8F042AHJ020SC00T

Temperature Sensor
Temperature Sensor Operation
PS022825-0908
The on-chip Temperature Sensor allows you to measure temperature on the die with either
the on-board ADC or on-board comparator. This block is factory calibrated for in-circuit
software correction. Uncalibrated accuracy is significantly worse, therefore the tempera-
ture sensor is not recommended for uncalibrated use.
The on-chip temperature sensor is a Proportional to Absolute Temperature (PTAT)
topology. A pair of Flash option bytes contain the calibration data. The temperature sensor
can be disabled by a bit in the
consumption.
The temperature sensor can be directly read by the ADC to determine the absolute value of
its output. The temperature sensor output is also available as an input to the comparator for
threshold type measurement determination. The accuracy of the sensor when used with the
comparator is substantially less than when measured by the ADC.
If the temperature sensor is routed to the ADC, the ADC must be configured in unity-gain
buffered mode (see
a signed number, although it is always positive.
The sensor is factory-trimmed through the ADC using the external 2.0 V reference. Unless
the sensor is re-trimmed for use with a different reference, it is most accurate when used
with the external 2.0 V reference.
Because this sensor is an on-chip sensor it is recommended that the user account for the
difference between ambient and die temperature when inferring ambient temperature
conditions.
During normal operation, the die undergoes heating that causes a mismatch between the
ambient temperature and that measured by the sensor. For best results, the
Z8 Encore! XP
die and ambient temperatures converge (this time is dependent on the thermal design of
the system). The temperature sensor measurement must then be made immediately after
recovery from STOP mode.
The following equation defines the transfer function between the temperature sensor
output voltage and the die temperature. This is needed for comparator threshold
measurements.
where, T is the temperature in °C; V is the sensor output in volts.
V
=
0.01
×
®
T
device must be placed into STOP mode for sufficient time such that the
+
Input Buffer Stage
0.65
Power Control Register 0
on page 129) The value read back from the ADC is
Z8 Encore! XP
on page 34 to reduce power
Product Specification
Temperature Sensor
®
F082A Series
139