max5264 Maxim Integrated Products, Inc., max5264 Datasheet - Page 11

• Manufacturer Part Number: max5264
• Description: Max5264 Octal, 14-bit, Voltage-output Dac With Parallel Interface For Ate
• Manufacturer: Maxim Integrated Products, Inc.

Table 4. Analog Voltage vs. Digital Code
The output amplifier multiplies V
output voltage range of 2
Further manipulation of the output voltage span is
accomplished by offsetting DUTGND. The output volt-
age of the MAX5264 is described by the following
equation:
where DATA is the numeric value of the DAC’s binary
input code, and DATA ranges from 0 to 16383
(2
1LSB, is described by the following equation:
Because the MAX5264 has precision buffers on its ref-
erence inputs, the requirements for interfacing to these
inputs are minimal. Select a low-drift, low-noise refer-
ence within the recommended REF+ and REF- voltage
ranges. The MAX5264 does not require bypass capaci-
tors on its reference inputs. Add capacitors only if the
reference voltage source requires them to meet system
specifications.
The MAX5264’s internal deglitch circuitry is enabled on
the falling edge of LD. Therefore, to achieve optimum
performance, drive LD low after the inputs are either
latched or steady state. This is best accomplished by
having the falling edge of LD occur at least 50ns after
the rising edge of CS.
Note: Output voltage is based on REF+ = +4.5V, REF- = -2.0V,
and DUTGND = 0.
14
V
- 1). The resolution of the MAX5264, defined as
11 1111 1111 1111
10 0000 0000 0000
01 0011 1011 0010
00 0000 0000 0001
00 0000 0000 0000
OUT
INPUT CODE
=
2 V
LSB
−



(
V
REF
OUTGND
______________________________________________________________________________________
=
+
2
(
−
REF
Minimizing Output Glitch
V
✕
REF
+ −
REF- to 2
2
Reference Selection
14
−
)
REF
DATA
DAC
2
14
VOLTAGE (V)
Octal, 14-Bit Voltage-Output DAC
−
+8.999207
-3.999207
✕
OUTPUT
by 2, yielding an
)
+2.500
+610µ
-4.000
+
REF+ (Figure 1).
V
REF
with Parallel Interface for ATE
−



For optimum performance, use a multilayer PC board
with an unbroken analog ground. For normal operation,
connect the four DUTGND pins directly to the ground
plane. Avoid sharing the connections of these sensitive
pins with other ground traces.
As with any sensitive data-acquisition system, connect
the digital and analog ground planes together at a sin-
gle point, preferably directly underneath the MAX5264.
Avoid routing digital signals underneath the MAX5264
to minimize their coupling into the IC.
For normal operation, bypass V
ceramic chip capacitors to the analog ground plane. To
enhance transient response and capacitive drive capa-
bility, add 10µF tantalum capacitors in parallel with the
ceramic capacitors. Note, however, that the MAX5264
does not require the additional capacitance for stability.
Bypass V
digital ground plane.
To guarantee proper operation of the MAX5264, ensure
that power is applied to V
ensure that V
ground. To prevent this situation, connect a Schottky
diode between V
shown in Figure 3. Do not power up the logic input pins
before establishing the supply voltages. If this is not
possible and the digital lines can drive more than
10mA, place current-limiting resistors (e.g., 470Ω) in
series with the logic pins.
Figure 3. Schottky Diode Between V
SYSTEM GND
CC
V
with a 0.1µF ceramic chip capacitor to the
SS
SS
1N5817
SS
is never more than 300mV above
Power Supplies, Grounding,
and the analog ground plane, as
Power-Supply Sequencing
DD
V
V
before V
SS
SS
SS
DD
and GND
MAX5264
and V
and Bypassing
GND
SS
and V
SS
with 0.1µF
CC
. Also
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