AD5762RCSUZ Analog Devices Inc, AD5762RCSUZ Datasheet - Page 27

• Manufacturer Part Number: AD5762RCSUZ
• Description: IC DAC DUAL 16BIT 1LSB 32-TQFP
• Manufacturer: Analog Devices Inc

Specifications of AD5762RCSUZ

• Data Interface: Serial
• Settling Time: 8µs
• Number Of Bits: 16
• Number Of Converters: 2
• Voltage Supply Source: Analog and Digital, Dual ±
• Power Dissipation (max): 180mW
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 32-TQFP, 32-VQFP
• Resolution (bits): 16bit
• Sampling Rate: 84.6MSPS
• Input Channel Type: Serial
• Supply Voltage Range - Digital: 2.7V To 5.25V
• Supply Current: 4.25mA
• Digital Ic Case Style: QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

DESIGN FEATURES
ANALOG OUTPUT CONTROL
In many industrial process control applications, it is vital that
the output voltage be controlled during power-up and during
brownout conditions. When the supply voltages are changing,
the VOUTx pins are clamped to 0 V via a low impedance path.
To prevent the output amp from being shorted to 0 V during this
time, Transmission Gate G1 is also opened (see Figure 42).
These conditions are maintained until the power supplies stabilize
and a valid word is written to the DAC register. G2 then opens,
and G1 closes. Both transmission gates are also externally control-
lable via the reset in ( RSTIN ) control input. For example, if
RSTIN is driven from a battery supervisor chip, the RSTIN
input is driven low to open G1 and close G2 on power-off or
during a brownout. Conversely, the on-chip voltage detector
output ( RSTOUT ) is also available to the user to control other
parts of the system. The basic transmission gate functionality is
shown in
DIGITAL OFFSET AND GAIN CONTROL
The AD5762R incorporates a digital offset adjust function with
a ±16 LSB adjust range and 0.125 LSB resolution. The gain register
allows the user to adjust the AD5762R full-scale output range.
The full-scale output can be programmed to achieve full-scale
ranges of ±10 V, ±10.25 V, and ±10.5 V. A fine gain trim is also
available.
PROGRAMMABLE SHORT-CIRCUIT PROTECTION
The short-circuit current (I
programmed by inserting an external resistor between the ISCC
pin and PGND. The programmable range for the current is
500 μA to 10 mA, corresponding to a resistor range of 120 kΩ
to 6 kΩ. The resistor value is calculated as follows:
R ≈
Figure 42
I
60
SC
CONTROL
VOLTAGE
MONITOR
AND
Figure 42. Analog Output Control Circuitry
.
RSTOUT
SC
) of the output amplifiers can be
G1
G2
RSTIN
AGNDA
VOUTA
Rev. A | Page 27 of 32
If the ISCC pin is left unconnected, the short-circuit current limit
defaults to 5 mA. It should be noted that limiting the short-circuit
current to a small value can affect the slew rate of the output
when driving into a capacitive load. Therefore, the value of the
short-circuit current that is programmed should take into account
the size of the capacitive load being driven.
DIGITAL I/O PORT
The AD5762R contains a 2-bit digital I/O port (D1 and D0).
These bits can be configured independently as inputs or outputs
and can be driven or have their values read back via the serial
interface. The I/O port signals are referenced to DV
When configured as outputs, they can be used as control signals
to multiplexers or can be used to control calibration circuitry
elsewhere in the system. When configured as inputs, the logic
signals from limit switches, for example, can be applied to D0
and D1 and can be read back using the digital interface.
DIE TEMPERATURE SENSOR
The on-chip die temperature sensor provides a voltage output
that is linearly proportional to the Celsius temperature scale. Its
nominal output voltage is 1.47 V at 25°C die temperature, varying
at 5 mV/°C, giving a typical output range of 1.175 V to 1.9 V over
the full temperature range. Its low output impedance and linear
output simplify interfacing to temperature control circuitry and
analog-to-digital converters (ADCs). The temperature sensor is
provided as more of a convenience than as a precise feature; it is
intended for indicating a die temperature change for recali-
bration purposes.
LOCAL GROUND OFFSET ADJUST
The AD5762R incorporates a local ground offset adjust feature
that, when enabled in the function register, adjusts the DAC
outputs for voltage differences between the individual DAC ground
pins and the REFGND pin, ensuring that the DAC output voltages
are always referenced to the local DAC ground pin. For example, if
the AGNDA pin is at +5 mV with respect to the REFGND pin
and VOUTA is measured with respect to AGNDA, a −5 mV error
results, enabling the local ground offset adjust feature to adjust
VOUTA by +5 mV, thereby eliminating the error.
CC
AD5762R
and DGND.