HI5728/6IN Intersil, HI5728/6IN Datasheet - Page 17

• Manufacturer Part Number: HI5728/6IN
• Description: DAC DUAL 10BIT 60MHZ 4- LQFP
• Manufacturer: Intersil

Specifications of HI5728/6IN

• Settling Time: 35ns
• Number Of Bits: 10
• Data Interface: Parallel
• Number Of Converters: 2
• Voltage Supply Source: Analog and Digital
• Power Dissipation (max): 330mW
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 48-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Full Scale Gain Error, is the error from an ideal ratio of 32
between the output current and the full scale adjust current
(through R
Full Scale Gain Drift, is measured by setting the data inputs to
all ones and measuring the output voltage through a known
resistance as the temperature is varied from T
defined as the maximum deviation from the value measured at
room temperature to the value measured at either T
T
Total Harmonic Distortion, THD, is the ratio of the DAC output
fundamental to the RMS sum of the first five harmonics.
Spurious Free Dynamic Range, SFDR, is the amplitude
difference from the fundamental to the largest harmonically or
non-harmonically related spur within the specified window.
Output Voltage Compliance Range, is the voltage limit
imposed on the output. The output impedance load should
be chosen such that the voltage developed does not violate
the compliance range.
Offset Error, is measured by setting the data inputs to all
zeros and measuring the output voltage through a known
resistance. Offset error is defined as the maximum deviation
of the output current from a value of 0mA.
Offset Drift, is measured by setting the data inputs to all zeros
and measuring the output voltage through a known resistance
as the temperature is varied from T
the maximum deviation from the value measured at room
temperature to the value measured at either T
The units are ppm of FSR (Full Scale Range) per °C.
Power Supply Rejection, is measured using a single power
supply. Its nominal +5V is varied
DAC full scale output is noted.
Reference Input Multiplying Bandwidth, is defined as the
3dB bandwidth of the voltage reference input. It is measured
by using a sinusoidal waveform as the external reference
with the digital inputs set to all 1s. The frequency is
increased until the amplitude of the output waveform is
0.707 of its original value.
Internal Reference Voltage Drift, is defined as the
maximum deviation from the value measured at room
temperature to the value measured at either T
The units are ppm per °C.
Detailed Description
The HI5728 is a dual, 10-bit, current out, CMOS, digital to
analog converter. Its maximum update rate is 125MSPS and
can be powered by either single or dual power supplies in
the recommended range of +3V to +5V. It consumes less
than 330mW of power when using a +5V supply with the
data switching at 100MSPS. The architecture is based on a
segmented current source arrangement that reduces glitch
by reducing the amount of current switching at any one time.
MAX
. The units are ppm of FSR (full scale range) per °C.
SET
).
17
±
MIN
10% and the change in the
to T
MAX
MIN
MIN
. It is defined as
MIN
to T
or T
MIN
or T
MAX
MAX
or
MAX
. It is
.
.
HI5728
The five MSBs are represented by 31 major current sources
of equivalent current. The five LSBs are comprised of binary
weighted current sources. Consider an input waveform to
the converter which is ramped through all the codes from 0
to 1023. The five LSB current sources would begin to count
up. When they reached the all high state (decimal value of
31) and needed to count to the next code, they would all turn
off and the first major current source would turn on. To
continue counting upward, the 5 LSBs would count up
another 31 codes, and then the next major current source
would turn on and the five LSBs would all turn off. The
process of the single, equivalent, major current source
turning on and the five LSBs turning off each time the
converter reaches another 31 codes greatly reduces the
glitch at any one switching point. In previous architectures
that contained all binary weighted current sources or a
binary weighted resistor ladder, the converter might have a
substantially larger amount of current turning on and off at
certain, worst-case transition points such as mid-scale and
quarter scale transitions. By greatly reducing the amount of
current switching at certain ‘major’ transitions, the overall
glitch of the converter is dramatically reduced, improving
settling times and transient problems.
Digital Inputs And Termination
The HI5728 digital inputs are guaranteed to CMOS levels.
However, TTL compatibility can be achieved by lowering the
supply voltage to 3V due to the digital threshold of the input
buffer being approximately half of the supply voltage. The
internal register is updated on the rising edge of the clock. To
minimize reflections, proper termination should be
implemented. If the lines driving the clock(s) and digital
inputs are 50Ω lines, then 50Ω termination resistors should
be placed as close to the converter inputs as possible.
Ground Plane(s)
If separate digital and analog ground planes are used, then all
of the digital functions of the device and their corresponding
components should be over the digital ground plane and
terminated to the digital ground plane. The same is true for the
analog components and the analog ground plane. Refer to the
Application Note on the HI5728 Evaluation Board for further
discussion of the ground plane(s) upon availability.
Noise Reduction
To minimize power supply noise, 0.1µF capacitors should be
placed as close as possible to the converter’s power supply
pins, AV
using separate digital and analog ground planes, these
capacitors should be terminated to the digital ground for
DV
of the power supplies on the board is recommended. See
the Application Note on the HI5728 Evaluation Board for
more information upon availability.
DD
and to the analog ground for AV
DD
and DV
DD
. Also, should the layout be designed
DD
. Additional filtering
January 22, 2010
FN4321.5