MAX535BCPA+ Maxim Integrated Products, MAX535BCPA+ Datasheet - Page 9

• Manufacturer Part Number: MAX535BCPA+
• Description: IC DAC V-OUT 13BIT 5V LP 8-DIP
• Manufacturer: Maxim Integrated Products

Specifications of MAX535BCPA+

• Settling Time: 16µs
• Number Of Bits: 13
• Data Interface: Serial
• Number Of Converters: 1
• Voltage Supply Source: Single Supply
• Power Dissipation (max): 552mW
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: 8-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX535/MAX5351 contain a 13-bit, voltage-output
digital-to-analog converter (DAC) that is easily
addressed using a simple 3-wire serial interface. It
includes a 16-bit shift register, and has a doubled-
buffered input composed of an input register and a
DAC register (see Functional Diagram ). In addition to
the voltage output, the amplifier’s negative input is
available to the user.
The DAC is an inverted R-2R ladder network that con-
verts a 13-bit digital input into an equivalent analog out-
put voltage in proportion to the applied reference
voltage input. Figure 1 shows a simplified circuit dia-
gram of the DAC.
The reference input accepts positive DC and AC sig-
nals. The voltage at the reference input sets the full-
scale output voltage for the DAC. The reference input
voltage range is 0V to (V
(V
age source as:
where NB is the numeric value of the DAC’s binary
input code (0 to 8191), V
and Gain is the externally set voltage gain.
The impedance at the reference input is code depen-
dent, ranging from a low value of 14kΩ when the DAC
has an input code of 1555 hex, to a high value exceed-
ing several giga ohms (leakage currents) with an input
_____________________Pin Description
_______________Detailed Description
OUT)
PIN
1
2
3
4
5
6
7
8
is represented by a digitally programmable volt-
V
OUT
NAME
SCLK
GND
OUT
V
DIN
REF
CS
FB
DD
= (V
_______________________________________________________________________________________
Low-Power, 13-Bit Voltage-Output DACs
REF
DAC Output Voltage
Chip-Select Input. Active low.
Serial-Data Input
Serial-Clock Input
DAC Output Amplifier Feedback
Reference Voltage Input
Ground
Positive Power Supply
x NB / 8192 ) x Gain
DD
REF
- 1.4V). The output voltage
is the reference voltage,
Reference Inputs
FUNCTION
code of 0000 hex. Because the input impedance at the
reference pin is code dependent, load regulation of the
reference source is important.
The REF reference input has a 14kΩ guaranteed mini-
mum input impedance. A voltage reference with a load
regulation of 6ppm/mA, such as the MAX873, would
typically deviate by 0.0062LSB (0.009LSB worst case)
when driving the MAX535 reference input at 2.5V.
In shutdown mode, the MAX535/MAX5351’s REF input
enters a high-impedance state with a typical input leak-
age current of 0.001µA.
The reference input capacitance is also code depen-
dent and typically ranges from 15pF (with an input
code of all 0s) to 50pF (with an input code of all 1s).
The MAX535/MAX5351’s DAC output is internally
buffered by a precision amplifier with a typical slew rate
of 0.6V/µs. Access to the output amplifier’s inverting
input provides the user greater flexibility in output gain
setting/signal conditioning (see the Applications
Information section).
With a full-scale transition at the MAX535/MAX5351 out-
put, the typical settling time to ±1/2LSB is 16µs when
loaded with 5kΩ in parallel with 100pF (loads less than
2kΩ degrade performance).
The MAX535 output amplifier’s output dynamic re-
sponses and settling performances are shown in the
Typical Operating Characteristics .
Figure 1. Simplified DAC Circuit Diagram
AGND
REF
SHOWN FOR ALL 1s ON DAC
with Serial Interface
2R
2R
D0
R
2R
D10
R
2R
D11
R
Output Amplifier
2R
D12
FB
OUT
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