ADP1046DC1-EVALZ Analog Devices, ADP1046DC1-EVALZ Datasheet - Page 28

• Manufacturer Part Number: ADP1046DC1-EVALZ
• Description: Daughter Cards & OEM Boards ADP1046 Daughter Card
• Manufacturer: Analog Devices
• Series: ADP1046r

Specifications of ADP1046DC1-EVALZ

• Rohs: yes
• Product: Daughter Cards
• Description/function: 100 kHz daughter board
• Interface Type: I2C
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Operating Supply Voltage: 3.3 V
• Factory Pack Quantity: 1
• For Use With: ADP1046

POWER READINGS
The output power value register (Register 0x19) is the product
of the VS3 voltage value and the CS2 current value. Therefore,
a combination of the formulas in the Voltage Readings section
and the CS2+, CS2− Pins section is used to calculate the power
reading in watts. This register is a 16-bit word. It multiplies two
12-bit numbers and discards the eight LSBs.
For example,
POWER MONITORING ACCURACY
The
to the full-scale range of the signal that it is measuring.
FIRST FLAG FAULT ID AND VALUE REGISTERS
When the
the value of the first fault in a dedicated register. For example,
if the overtemperature (OTP) fault is registered followed by an
OVP fault, the OTP flag is stored in the first flag ID register
(Register 0x10). This register gives the user more information
for fault diagnosis than a simple flag. The contents of this register
are latched, meaning that they are stored until read by the user.
The contents are also reset by toggling PSON. If a flag is set to
be ignored, it does not appear in the first flag register.
EXTERNAL FLAG INPUT (FLAGIN PIN)
The FLAGIN pin can be used to send an external fault signal
into the ADP1046. Register 0x0A[3:0] can be used to program
the FLAGIN flag to trigger an action.
TEMPERATURE READINGS (RTD PIN)
The RTD pin is set up for use with an external negative tempera-
ture coefficient (NTC) thermistor. The RTD pin has an internal
programmable current source. An ADC monitors the voltage
on the RTD pin.
The RTD temperature value register, Register 0x1A, is updated
every 10 ms. The
and then outputs the average value at the end of the 10 ms period.
The RTD ADC has an input range of 1.6 V and a resolution of
12 bits, which means that the LSB size is 1.6 V/4096 = 390.625 µV.
The user is limited to an input range of 1.3 V, which means that the
maximum ADC output code is limited to 1.3 V/390.6 µV = 3328.
ADP1046
ADP1046
P
P
OUT
OUT
= V
= 12 V × 4.453 A = 53.436 W
ADP1046
OUT
power monitoring accuracy is specified relative
× I
ADP1046
OUT
registers several fault conditions, it stores
100kΩ
NTC
stores every ADC sample for 10 ms
16.5kΩ
RTD
RTD TEMPERATURE
VALUE REGISTER
REG 0x1A[15:4]
10µA/20µA/30µA/40µA
ADC
RTD
Figure 37. RTD Pin Internal Details
Rev. B | Page 28 of 92
RTD TEMPERATURE
CONDITIONING
REG 0x1B[7:0]
VALUE IN °C
SIGNAL
The output of the RTD ADC is linearly proportional to the vol-
tage on the RTD pin. However, thermistors exhibit a nonlinear
function of resistance vs. temperature. Therefore, the user must
perform postprocessing on the RTD ADC reading to accurately
read the temperature.
By connecting an external resistor (R
NTC thermistor (TH), a constant current can be used to
achieve linearization (see Figure 36).
An internal, precision current source of 10 µA, 20 µA, 30 µA,
or 40 µA can be selected in Register 0x11. This current source
can be trimmed by means of an internal DAC to compensate
for thermistor accuracy (see the RTD/OTP Trim section). The
user can select the output current source using Bits[7:6] of
Register 0x11.
The
preselected combination of external components and current
selection for best performance when measuring linearized
temperatures in degrees Celsius in the industrial range.
For more information about the required thermistor and
selecting and trimming the precision current sources, see
the Temperature Linearization Scheme section.
Optionally, the user can process the RTD reading and perform
postprocessing in the form of a lookup table or polynomial
equation to match the specific NTC thermistor used. With the
internal current source set to 46 µA, the equation to calculate
the ADC code at a specified NTC thermistor value (Rx) is given
by the following formula:
For example, at 60°C, the NTC thermistor at the RTD pin is
21.82 kΩ.
ADP1046
ADC CODE = 46 µA × Rx/1.6 × 4096
RTD_ADC_CODE = 46 µA × 21.82 kΩ/1.6 × 4096 = 2570
REG 0x2F[7:0]
THRESHOLD
Figure 36. Temperature Measurement Using Thermistor
OTP
implements a linearization scheme based on a
R
EXT
FLAG
OTP
TH
RTD
FLAGS
EXT
DAC
ADC
) in parallel with the
Data Sheet