AD AD5533B 32-channel precision infinite sample-and-hold Datasheet

a
32-Channel Precision
Infinite Sample-and-Hold
AD5533B*
GENERAL DESCRIPTION
FEATURES
Infinite Sample-and-Hold Capability to ⴞ0.018% Accuracy
Infinite Sample-and-Hold Total Unadjusted Error ⴞ2.5 m V
High Integration:
32-Channel DAC in 12 mm ⴛ 12 mm CSPBGA
Per Channel Acquisition Time of 16 ␮s Max
Adjustable Voltage Output Range
Output Impedance 0.5 ⍀
Output Voltage Span 10 V
Readback Capability
DSP/Microcontroller Compatible Serial Interface
Parallel Interface
Temperature Range –40ⴗC to +85ⴗC
The AD5533B combines a 32-channel voltage translation function
with an infinite output hold capability. An analog input voltage on
the common input pin, VIN, is sampled and its digital representation transferred to a chosen DAC register. VOUT for this DAC
is then updated to reflect the new contents of the DAC register.
Channel selection is accomplished via the parallel address inputs
A0–A4 or via the serial input port. The output voltage range is
determined by the offset voltage at the OFFS_IN pin and the gain
of the output amplifier. It is restricted to a range from VSS + 2 V
to VDD – 2 V because of the headroom of the output amplifier.
The device is operated with AVCC = +5 V ± 5%, DVCC = +2.7 V
to +5.25 V, VSS = –4.75 V to –16.5 V, and VDD = +8 V to
+16.5 V and requires a stable 3 V reference on REF_IN as well
as an offset voltage on OFFS_IN.
APPLICATIONS
Optical Networks
Automatic Test Equipment
Level Setting
Instrumentation
Industrial Control Systems
Data Acquisition
Low Cost I/O
PRODUCT HIGHLIGHTS
1. Precision infinite droopless sample-and-hold capability.
2. The AD5533B is available in a 74-lead CSPBGA with a
body size of 12 mm ⫻ 12 mm.
3. In infinite sample-and-hold mode, a total unadjusted error of
± 2.5 mV is achieved by laser-trimming on-chip resistors.
FUNCTIONAL BLOCK DIAGRAM
DVCC AVCC
REF IN REF OUT
OFFS IN
VDD
VSS
VOUT 0
VIN
DAC
ADC
TRACK / RESET
BUSY
DAC GND
VOUT 31
AD5533B
DAC
AGND
OFFS OUT
DAC
DGND
SER / PAR
INTERFACE
CONTROL
LOGIC
SCLK DIN DOUT
ADDRESS INPUT REGISTER
SYNC/CS
A4 –A0
CAL
WR
OFFSET SEL
*Protected by U.S. Patent No. 5,969,657; other patents pending.
REV. A
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties that
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2002
(VDD = +8 V to +16.5 V, VSS = –4.75 V to –16.5 V; AVCC = +4.75 V to +5.25 V;
DV = 2.7 V to 5.25 V; AGND = DGND = DAC_GND = 0 V; REF_IN = 3 V; OFFS_IN = 0 V;
AD5533B–SPECIFICATIONS
Output Range from V + 2 V to V – 2 V. All outputs unloaded. All specifications T to T , unless otherwise noted.)
CC
SS
DD
Parameter1
MIN
MAX
B Version2
Unit
Conditions/Comments
± 0.006
± 0.018
% typ
% max
Input Range 100 mV to 2.96 V
After Gain and Offset Adjustment
± 2.5
± 12
mV typ
mV max
See TPC 6.
3.51/3.52/3.53
±1
± 10
min/typ/max
mV typ
mV max
0 to 3
70
V
mV max
Input Upper Dead Band
40
mV max
Input Current
1
µA max
Input Capacitance3
20
pF typ
0/4
V min/max
1
µA max
Output Range Restricted from
VSS + 2 V to VDD – 2 V
100 nA typ
3.0
2.85/3.15
1
V
V min/max
µA max
<1 nA typ
3
280
60
kΩ typ
ANALOG CHANNEL
VIN to VOUT Nonlinearity
Total Unadjusted Error (TUE)
Gain
Offset Error
ANALOG INPUT (VIN)
Input Voltage Range
Input Lower Dead Band
ANALOG INPUT (OFFS_IN)
Input Voltage Range
Input Current
VOLTAGE REFERENCE
REF_IN
Nominal Input Voltage
Input Voltage Range3
Input Current
REF_OUT
Output Voltage
Output Impedance3
Reference Temperature Coefficient3
ANALOG OUTPUTS (VOUT 0–31)
Output Temperature Coefficient3, 4
DC Output Impedance
Output Range
Resistive Load3, 5
Capacitive Load3, 5
Short-Circuit Current3
DC Power Supply Rejection Ratio3
DC Crosstalk3
ANALOG OUTPUT (OFFS_OUT)
Output Temperature Coefficient3, 4
DC Output Impedance3
Output Range
Output Current
Capacitive Load
DIGITAL INPUTS3
Input Current
Input Low Voltage
Input High Voltage
Input Hysteresis (SCLK and CS Only)
Input Capacitance
See TPC 2.
Nominal Input Range
50 mV typ. Referred to VIN.
See Figure 5.
12 mV typ. Referred to VIN.
See Figure 5.
100 nA typ. VIN acquired on
one channel.
V typ
ppm/°C typ
10
0.5
VSS + 2/VDD – 2
5
100
7
–70
–70
250
ppm/°C typ
Ω typ
V min/max
pF max
mA typ
dB typ
dB typ
µV max
10
1.3
50 to REF_IN – 12
10
100
mV typ
µA max
pF max
± 10
0.8
0.4
2.4
2.0
200
10
µA max
V max
V max
V min
V min
mV typ
pF max
–2–
100 µA Output Load
kΩ min
VDD = +15 V ± 5%
VSS = –15 V ± 5%
Outputs Loaded
ppm/°C typ
kΩ typ
Source Current
5 µA typ
DVCC = 5 V ±
DVCC = 3 V ±
DVCC = 5 V ±
DVCC = 3 V ±
5%
10%
5%
10%
REV. A
AD5533B
Parameter1
B Version2
Unit
Conditions/Comments
0.4
4.0
0.4
2.4
±1
15
V max
V min
V max
V min
µA max
pF typ
DVCC = 5 V. Sinking 200 µA.
DVCC = 5 V. Sourcing 200 µA.
DVCC = 3 V. Sinking 200 µA.
DVCC = 3 V. Sourcing 200 µA.
DOUT Only
DOUT Only
8/16.5
–4.75/–16.5
4.75/5.25
2.7/5.25
V min/max
V min/max
V min/max
V min/max
15
15
33
1.5
280
mA max
mA max
mA max
mA max
mW typ
3
DIGITAL OUTPUTS (BUSY, DOUT)
Output Low Voltage
Output High Voltage
Output Low Voltage
Output High Voltage
High Impedance Leakage Current
High Impedance Output Capacitance
POWER REQUIREMENTS
Power Supply Voltages
VDD
VSS
AVCC
DVCC
Power Supply Currents6
IDD
ISS
AICC
DICC
Power Dissipation6
10 mA typ. All channels full-scale.
10 mA typ. All channels full-scale.
26 mA typ
1 mA typ
VDD = +10 V, VSS = –5 V
NOTES
1
See Terminology section.
2
B Version: Industrial temperature range –40°C to +85°C; typical at +25°C.
3
Guaranteed by design and characterization, not production tested.
4
AD780 as reference for the AD5533B.
5
Ensure that you do not exceed T J (max). See Absolute Maximum Ratings.
6
Outputs unloaded.
Specifications subject to change without notice.
(VDD = +8 V to +16.5 V, VSS = –4.75 V to –16.5 V; AVCC = +4.75 V to +5.25 V; DVCC = +2.7 V to +5.25 V;
AGND = DGND = DAC_GND = 0 V; REF_IN = 3 V; OFFS_IN = 0 V; Output Range from VSS + 2 V to VDD – 2 V.
All outputs unloaded. All specifications TMIN to TMAX, unless otherwise noted.)
AC CHARACTERISTICS
Parameter
2
Output Settling Time
Acquisition Time
OFFS_IN Settling Time2
Digital Feedthrough2
Output Noise Spectral Density @ 1 kHz2
AC Crosstalk2
B Version1
Unit
Conditions/Comments
3
16
10
0.2
400
5
µs max
µs max
µs max
nV-s typ
nV/√Hz typ
nV-s typ
500 pF, 5 kΩ Load; 0 V–3 V Step
NOTES
1
B version: Industrial temperature range –40°C to +85°C; typical at 25°C.
2
Guaranteed by design and characterization, not production tested.
Specifications subject to change without notice.
REV. A
–3–
AD5533B
TIMING CHARACTERISTICS
PARALLEL INTERFACE
Parameter1, 2
Limit at TMIN, TMAX
(B Version)
Unit
Conditions/Comments
t1
t2
t3
t4
t5
t6
0
0
50
50
20
7
ns min
ns min
ns min
ns min
ns min
ns min
CS to WR Setup Time
CS to WR Hold Time
CS Pulsewidth Low
WR Pulsewidth Low
A4–A0, CAL, OFFS_SEL to WR Setup Time
A4–A0, CAL, OFFS_SEL to WR Hold Time
NOTES
1
See Parallel Interface Timing Diagram.
2
Guaranteed by design and characterization, not production tested.
Specifications subject to change without notice.
SERIAL INTERFACE
Parameter1, 2
Limit at TMIN, TMAX
(B Version)
Unit
Conditions/Comments
fCLKIN
t1
t2
t3
t4
t5
t6
t7
t8 3
t9 3
t10
t114
20
20
20
15
50
10
5
5
20
60
400
7
MHz max
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns max
ns max
ns min
ns min
SCLK Frequency
SCLK High Pulsewidth
SCLK Low Pulsewidth
SYNC Falling Edge to SCLK Falling Edge Setup Time
SYNC Low Time
DIN Setup Time
DIN Hold Time
SYNC Falling Edge to SCLK Rising Edge Setup Time for Readback
SCLK Rising Edge to DOUT Valid
SCLK Falling Edge to DOUT High Impedance
10th SCLK Falling Edge to SYNC Falling Edge for Readback
SCLK Falling Edge to SYNC Falling Edge Setup Time for
Readback
NOTES
1
See Serial Interface Timing Diagrams.
2
Guaranteed by design and characterization, not production tested.
3
These numbers are measured with the load circuit of Figure 2.
4
SYNC should be taken low while SCLK is low for readback.
Specifications subject to change without notice.
PARALLEL INTERFACE TIMING DIAGRAM
CS
200␮A
TO
OUTPUT
PIN
WR
1.6V
CL
50pF
200␮A
A4–A0, CAL,
OFFS SEL
Figure 1. Parallel Write (ISHA Mode Only)
IOL
IOH
Figure 2. Load Circuit for DOUT Timing Specifications
–4–
REV. A
AD5533B
SERIAL INTERFACE TIMING DIAGRAMS
t1
SCLK
1
2
3
4
5
6
7
8
9
10
t2
t3
SYNC
t4
t5
t6
DIN
MSB
LSB
Figure 3. 10-Bit Write (ISHA Mode and Both Readback Modes)
t1
t7
SCLK
1
10
2
t11
3
4
5
6
7
8
9
10
11
12
13
14
t2
SYNC
t10
t4
t8
t9
DOUT
MSB
LSB
Figure 4. 14-Bit Read (Both Readback Modes)
REV. A
–5–
AD5533B
ABSOLUTE MAXIMUM RATINGS 1, 2
Max Continuous Load Current at TJ = 70°C,
per Channel Group . . . . . . . . . . . . . . . . . . . . . . . 15.5 mA4
(TA = 25°C, unless otherwise noted.)
VDD to AGND . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +17 V
VSS to AGND . . . . . . . . . . . . . . . . . . . . . . . . +0.3 V to –17 V
AVCC to AGND, DAC_GND . . . . . . . . . . . . . –0.3 V to +7 V
DVCC to DGND . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +7 V
Digital Inputs to DGND . . . . . . . . . . –0.3 V to DVCC + 0.3 V
Digital Outputs to DGND . . . . . . . . . –0.3 V to DVCC + 0.3 V
REF_IN to AGND, DAC_GND . . . . –0.3 V to AVCC + 0.3 V
VIN to AGND, DAC_GND . . . . . . . . –0.3 V to AVCC + 0.3 V
VOUT0–31 to AGND . . . . . . . . . . VSS – 0.3 V to VDD + 0.3 V
OFFS_IN to AGND . . . . . . . . . . VSS – 0.3 V to VDD + 0.3 V
OFFS_OUT to AGND . . . . AGND – 0.3 V to AVCC + 0.3 V
AGND to DGND . . . . . . . . . . . . . . . . . . . . –0.3 V to +0.3 V
Operating Temperature Range
Industrial . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to +85°C
Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C
Junction Temperature (TJ max) . . . . . . . . . . . . . . . . . . 150°C
74-Lead CSPBGA Package, θJA Thermal Impedance . . 41°C/W
Reflow Soldering
Peak Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C
Time at Peak Temperature . . . . . . . . . . . . 10 sec to 40 sec
Max Power Dissipation . . . . . . . . . . . . (150°C – TA)/θJA mW3
NOTES
1
Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the
device at these or any other conditions above those listed in the operationa l sections
of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
2
Transient currents of up to 100 mA will not cause SCR latch-up.
3
This limit includes load power.
4
This maximum allowed continuous load current is spread over eight channels,
with channels grouped as follows:
Group 1: Channels 3, 4, 5, 6, 7, 8, 9, 10
Group 2: Channels 14, 16, 18, 20, 21, 24, 25, 26
Group 3: Channels 15, 17, 19, 22, 23, 27, 28, 29
Group 4: Channels 0, 1, 2, 11, 12, 13, 30, 31
For higher junction temperatures, derate as follows:
TJ (°C)
Max Continuous
Load Current
per Group (mA)
70
90
100
110
125
135
150
15.5
9.025
6.925
5.175
3.425
2.55
1.5
ORDERING GUIDE
Description
Function
AD5533BBC-1
AD5533ABC-1*
AD5532ABC-1*
AD5532ABC-2*
AD5532ABC-3*
AD5532ABC-5*
AD5532BBC-1*
EVAL-AD5533EB
32-Channel Precision ISHA Only
32-Channel ISHA Only
32 DACs, 32-Channel ISHA
32 DACs, 32-Channel ISHA
32 DACs, 32-Channel ISHA
32 DACs, 32-Channel ISHA
32 DACs, 32-Channel Precision ISHA
AD5532/AD5533 Evaluation Board
Output
Impedance
(Typ)
Output
Voltage Span Package
(V)
Description
Package
Option
0.5 Ω
0.5 Ω
0.5 Ω
0.5 Ω
500 Ω
1 kΩ
0.5 Ω
10
10
10
20
10
10
10
BC-74
BC-74
BC-74
BC-74
BC-74
BC-74
BC-74
74-Lead CSPBGA
74-Lead CSPBGA
74-Lead CSPBGA
74-Lead CSPBGA
74-Lead CSPBGA
74-Lead CSPBGA
74-Lead CSPBGA
*Separate Data Sheet
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection. Although
the AD5533B features proprietary ESD protection circuitry, permanent damage may occur on
devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are
recommended to avoid performance degradation or loss of functionality.
–6–
WARNING!
ESD SENSITIVE DEVICE
REV. A
AD5533B
PIN CONFIGURATION
1
2
3
4
5
6
7
8
9
10 11
A
A
B
B
C
C
D
D
E
E
F
F
G
G
H
H
J
J
K
K
L
L
1
2
3
4
5
6
7
8
9
10 11
74-Lead CSPBGA Ball Configuration
CSPBGA
Number
Ball
Name
CSPBGA
Number
Ball
Name
CSPBGA
Number
Ball
Name
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
B1
B2
B3
B4
B5
B6
B7
B8
B9
B10
B11
C1
C2
C6
NC*
A4
A2
A0
CS/SYNC
DVCC
SCLK
OFFSET_SEL
BUSY
TRACK/RESET
NC*
VO16
NC*
A3
A1
WR
DGND
DIN
CAL
SER/PAR
DOUT
REF_IN
VO18
DAC_GND1
NC*
C10
C11
D1
D2
D10
D11
E1
E2
E10
E11
F1
F2
F10
F11
G1
G2
G10
G11
H1
H2
H10
H11
J1
J2
J6
AVCC1
REF_OUT
VO20
DAC_GND2
AVCC2
OFFS_OUT
VO26
VO14
AGND1
OFFS_IN
VO25
VO21
AGND2
VO6
VO24
VO8
VO5
VO3
VO23
VIN
VO4
VO7
VO22
VO19
VSS2
J10
J11
K1
K2
K3
K4
K5
K6
K7
K8
K9
K10
K11
L1
L2
L3
L4
L5
L6
L7
L8
L9
L10
L11
VO9
VO11
VO17
VO15
VO27
VSS3
VSS1
VSS4
VDD2
VO2
VO10
VO13
VO12
NC*
VO28
VO29
VO30
VDD3
VDD1
VDD4
VO31
VO0
VO1
NC*
*NC = Not Connected
REV. A
–7–
AD5533B
PIN FUNCTION DESCRIPTIONS
Pin
Function
AGND (1–2)
AVCC (1–2)
VDD (1–4)
VSS (1–4)
DGND
DVCC
DAC_GND (1–2)
REF_IN
REF_OUT
VOUT (0–31)
VIN
A4–A11, A02
CAL1
CS/SYNC
Analog GND Pins
Analog Supply Pins. Voltage range from 4.75 V to 5.25 V.
VDD Supply Pins. Voltage range from 8 V to 16.5 V.
VSS Supply Pins. Voltage range from –4.75 V to –16.5 V.
Digital GND Pins
Digital Supply Pins. Voltage range from 2.7 V to 5.25 V.
Reference GND Supply for all the DACs
Reference Voltage for Channels 0–31
Reference Output Voltage
Analog Output Voltages from the 32 Channels
Analog Input Voltage
Parallel Interface. 5-address pins for 32 channels. A4 = MSB of channel address. A0 = LSB.
Parallel Interface. Control input that allows all 32 channels to acquire VIN simultaneously.
This pin is both the active low chip select pin for the parallel interface and the frame synchronization pin for
the serial interface.
Parallel Interface. Write pin. Active low. This is used in conjunction with the CS pin to address the device
using the parallel interface.
Parallel Interface. Offset select pin. Active high. This is used to select the offset channel.
Serial Clock Input for Serial Interface. This operates at clock speeds up to 20 MHz.
Data Input for Serial Interface. Data must be valid on the falling edge of SCLK.
Output from the DAC Registers for Readback. Data is clocked out on the rising edge of SCLK and is valid
on the falling edge of SCLK.
This pin allows the user to select whether the serial or parallel interface will be used. If the pin is tied low,
the parallel interface will be used. If it is tied high, the serial interface will be used.
Offset Input. The user can supply a voltage here to offset the output span. OFFS_OUT can also be tied to
this pin if the user wants to drive this pin with the offset channel.
Offset Output. This is the acquired/programmed offset voltage that can be tied to the OFFS_IN pin to
offset the span.
This output tells the user when the input voltage is being acquired. It goes low during acquisition and
returns high when the acquisition operation is complete.
If this input is held high, VIN is acquired once the channel is addressed. While it is held low, the input to the
gain/offset stage is switched directly to VIN. The addressed channel begins to acquire VIN on the rising edge
of TRACK. See TRACK Input section for further information. This input can also be used as a means of
resetting the complete device to its power-on-reset conditions. This is achieved by applying a low going
pulse of between 90 ns and 200 ns to this pin. See section on RESET Function for further details.
WR1
OFFSET_SEL1
SCLK2
DIN2
DOUT
SER/PAR1
OFFS_IN
OFFS_OUT
BUSY
TRACK/RESET2
NOTES
1
Internal pull-down devices on these logic inputs. Therefore, they can be left floating and will default to a logic low condition.
2
Internal pull-up devices on these logic inputs. Therefore, they can be left floating and will default to a logic high condition.
–8–
REV. A
AD5533B
TERMINOLOGY
VIN to VOUT Nonlinearity
DC Power Supply Rejection Ratio
DC Power Supply Rejection Ratio (PSRR) is a measure of
the change in analog output for a change in supply voltage
(VDD and VSS). It is expressed in dBs. VDD and VSS are varied ±5%.
This is a measure of the maximum deviation from a straight line
passing through the endpoints of the VIN versus VOUT transfer
function. It is expressed as a percentage of the full-scale span.
DC Crosstalk
This is the dc change in the output level of one channel in response
to a full-scale change in the output of all other channels. It is
expressed in µV.
Total Unadjusted Error (TUE)
This is a comprehensive specification that includes relative accuracy, gain, and offset errors. It is measured by sampling a range
of voltages on VIN and comparing the measured voltages on
VOUT to the ideal value. It is expressed in mV.
Output Settling Time
This is the time taken from when BUSY goes high to when the
output has settled to ± 0.018%.
Offset Error
This is a measure of the output error when VIN = 70 mV. Ideally,
with VIN = 70 mV:
Acquisition Time
This is the time taken for the VIN input to be acquired. It is the
length of time that BUSY stays low.
VOUT = (Gain × 70) − ((Gain − 1) × VOFFS _ IN ) mV
Offset error is a measure of the difference between VOUT (actual)
and VOUT (ideal). It is expressed in mV and can be positive or
negative. See Figure 5.
OFFS_IN Settling Time
Gain Error
Digital Feedthrough
This is the time taken from a 0 V–3 V step change in input
voltage on OFFS_IN until the output has settled to within ± 0.39%.
Gain Error = Actual Full- Scale Output −
This is a measure of the impulse injected into the analog outputs
from the digital control inputs when the part is not being written
to, i.e., CS/SYNC is high. It is specified in nV-secs and is measured
with a worst-case change on the digital input pins, e.g., from all
0s to all 1s and vice versa.
Ideal Full- Scale Output Offset − Error
Output Noise Spectral Density
This is a measure of the span error of the analog channel. It is
the deviation in slope of the transfer function. See Figure 5. It is
calculated as:
This is a measure of internally generated random noise. Random
noise is characterized as a spectral density (voltage per root Hertz).
It is measured by acquiring 1.5 V on all channels and measuring
noise at the output. It is measured in nV/√Hz typ.
where
Ideal Full- Scale Output = (Gain × 2.96) − ((Gain − 1) × VOFFS _ IN )
Ideal Gain = 3.52
AC Crosstalk
Output Temperature Coefficient
This is the area of the glitch that occurs on the output of one channel while another channel is acquiring. It is expressed in nV-secs.
This is a measure of the change in analog output with changes in
temperature. It is expressed in ppm/°C.
VOUT
GAIN ERROR +
OFFSET ERROR
IDEAL
TRANSFER
FUNCTION
ACTUAL
TRANSFER
FUNCTION
OFFSET
ERROR
0V
70mV
2.96
LOWER
DEAD BAND
Figure 5. ISHA Transfer Function
REV. A
3V
UPPER
DEAD BAND
–9–
VIN
AD5533B–Typical Performance Characteristics
0.0024
TA = 25 C
VREFIN = 3V
VOFFS_IN = 0V
0.0020
0.0016
5V
100
0.0008
VOUT
0.0004
0.0000
–0.0004
TA = 25ⴗC
VREFIN = 3V
VIN = 0V TO 1.5V
–0.0008
10
–0.0012
0%
–0.0016
–0.0020
2␮s
1V
–0.0024
0.1
2.96
VIN – V
TPC 4. Acquisition Time and Output Settling Time
TPC 1. VIN to VOUT Accuracy After Offset and
Gain Adjustment
3.530
4
70k
TA = 25 C
VREFIN = 3V
VIN = 1.5V
VOFFS_IN = 0V
60k
3.525
3.520
2
OFFSET ERROR
40k
30k
20k
3.515
1
63791
50k
FREQUENCY
GAIN
GAIN
OFFSET ERROR – mV
3
10k
1545
200
0
–40
0
40
TEMPERATURE – C
3.500
120
80
0
TPC 2. Offset Error and Gain vs. Temperature
3.530
5.2670
5.2676
VOUT – V
5.2682
TPC 5. ISHA Mode Repeatability (64 K Acquisitions)
40
TA = 25ⴗC
VREFIN = 3V
VIN = 1V
FREQUENCY
3.525
VOUT – V
VOUT ERROR – V
BUSY
90
0.0012
20
3.520
3.515
6
4
2
0
–2
SINK/SOURCE CURRENT – mA
–4
0
–6
–4
–3
–2
–1
0
1
2
3
4
5
TOTAL UNADJUSTED ERROR – mV
6
7
8
TPC 6. TUE Distribution at 25°C (ISHA Mode)
TPC 3. VOUT Source and Sink Capability
–10–
REV. A
AD5533B
FUNCTIONAL DESCRIPTION
ADDRESSED CHANNEL
The AD5533B can be thought of as consisting of an ADC and
32 DACs in a single package. The input voltage VIN is sampled
and converted into a digital word. The digital result is loaded into
one of the DAC registers and is converted (with gain and offset)
into an analog output voltage (VOUT0–VOUT31). Since the channel output voltage is effectively the output of a DAC there is no
droop associated with it. As long as power to the device is maintained, the output voltage will remain constant until this channel
is addressed again.
VIN
C2
7.5pF
C1
20pF
Figure 6. Analog Input Circuit
To update a single channel’s output voltage, the required new
voltage level is set up on the common input pin, VIN. The desired
channel is then addressed via the parallel port or the serial port.
When the channel address has been loaded, provided TRACK is
high, the circuit begins to acquire the correct code to load to the
DAC so that the DAC output matches the voltage on VIN. The
BUSY pin goes low and remains so until the acquisition is complete. The noninverting input to the output buffer is tied to VIN
during the acquisition period to avoid spurious outputs while the
DAC acquires the correct code. The acquisition is completed in
16 µs max. The BUSY pin goes high and the updated DAC output
assumes control of the output voltage. The output voltage of the
DAC is connected to the noninverting input of the output buffer.
Since the internal DACs are offset by 70 mV (max) from GND,
the minimum VIN in ISHA mode is 70 mV. The maximum VIN is
2.96 V due to the upper dead band of 40 mV (max).
Large source impedances will significantly affect the performance
of the ADC. This may necessitate the use of an input buffer
amplifier.
Output Buffer Stage—Gain and Offset
The function of the output buffer stage is to translate the
50 mV–3 V typical output of the DAC to a wider range. This
is done by gaining up the DAC output by 3.52 and offsetting
the voltage by the voltage on OFFS_IN pin.
VOUT = 3.52 × VDAC − 2.52 × VOFFS_IN
VDAC is the output of the DAC.
VOFFS_IN is the voltage at the OFFS_IN pin.
Table I shows how the output range on VOUT relates to the
offset voltage supplied by the user.
Table I. Sample Output Voltage Ranges
VOFFS_IN (V)
VDAC (V)
VOUT (V)
0
1
2.130
0.05 to 3
0.05 to 3
0.05 to 3
0.176 to 10.56
–2.34 to +8.04
–5.192 to +5.192
On power-on, all the DACs, including the offset channel, are loaded
with zeros. Each of the 33 DACs is offset internally by 50 mV (typ)
from GND so the outputs VOUT0 to VOUT31 are 50 mV (typ) on
power-on if the OFFS_IN pin is driven directly by the on-board
offset channel (OFFS_OUT), i.e., if OFFS_IN = OFFS_OUT =
50 mV = > VOUT = (Gain ⫻ VDAC) – (Gain – 1) ⫻ VOFFS_IN = 50 mV.
VOUT is limited only by the headroom of the output amplifiers.
VOUT must be within maximum ratings.
Analog Input
Offset Voltage Channel
The equivalent analog input circuit is shown in Figure 6. The
capacitor C1 is typically 20 pF and can be attributed to pin capacitance and 32 off-channels. When a channel is selected, an extra
7.5 pF (typ) is switched in. This capacitor C2 is charged to the
previously acquired voltage on that particular channel so it must
charge/discharge to the new level. It is essential that the external
source can charge/discharge this additional capacitance within
1 µs–2 µs of channel selection so that VIN can be acquired accurately. For this reason, a low impedance source is recommended.
The offset voltage can be externally supplied by the user at
OFFS_IN or it can be supplied by an additional offset voltage
channel on the device itself. The required offset voltage is set up
on VIN and acquired by the offset DAC. This offset channel’s DAC
output is directly connected to OFFS_OUT. By connecting
OFFS_OUT to OFFS_IN, this offset voltage can be used as the
offset voltage for the 32 output amplifiers. It is important to
choose the offset so that VOUT is within maximum ratings.
PIN
DRIVER
VIN
CONTROLLER
CONTROLLER
DAC
OUTPUT
STAGE
ACQUISITION
ACQUISITION
CIRCUIT
CIRCUIT
BUSY
VOUT1
DEVICE
UNDER
TEST
AD5533B
TRACK
THRESHOLD
VOLTAGE
ONLY ONE CHANNEL SHOWN FOR SIMPLICITY
Figure 7. Typical ATE Circuit Using TRACK Input
REV. A
–11–
AD5533B
Reset Function
1. ISHA Mode
The reset function on the AD5533B can be used to reset all
nodes on this device to their power-on-reset condition. This is
implemented by applying a low-going pulse of between 90 ns and
200 ns to the TRACK/RESET pin on the device. If the applied
pulse is less than 90 ns, it is assumed to be a glitch and no operation takes place. If the applied pulse is wider than 200 ns, this pin
adopts its track function on the selected channel, VIN is switched to
the output buffer, and an acquisition on the channel will not occur
until a rising edge of TRACK.
In this standard mode, a channel is addressed and that channel
acquires the voltage on VIN. This mode requires a 10-bit
write (see Figure 3) to address the relevant channel
(VOUT0–VOUT31, offset channel, or all channels). MSB is
written first.
2. Acquire and Readback Mode
This mode allows the user to acquire VIN and read back the
data in a particular DAC register. The relevant channel is
addressed (10-bit write, MSB first) and VIN is acquired in 16 µs
(max). Following the acquisition, after the next falling edge of
SYNC, the data in the relevant DAC register is clocked out
onto the DOUT line in a 14-bit serial format (see Figure 4).
During readback, DIN is ignored. The full acquisition time
must elapse before the DAC register data can be clocked out.
TRACK Function
Normally in ISHA mode of operation, TRACK is held high and
the channel begins to acquire when it is addressed. However, if
TRACK is low when the channel is addressed, VIN is switched
to the output buffer and an acquisition on the channel will not
occur until a rising edge of TRACK. At this stage the BUSY pin
will go low until the acquisition is complete, at which point the
DAC assumes control of the voltage to the output buffer and
VIN is free to change again without affecting this output value.
3. Readback Mode
Again, this is a readback mode but no acquisition is performed.
The relevant channel is addressed (10-bit write, MSB first) and
on the next falling edge of SYNC, the data in the relevant DAC
register is clocked out onto the DOUT line in a 14-bit serial format
(see Figure 4). The user must allow 400 ns (min) between the
last SCLK falling edge in the 10-bit write and the falling edge
of SYNC in the 14-bit readback. The serial write and read words
can be seen in Figure 8.
This is useful in an application where the user wants to ramp up
VIN until VOUT reaches a particular level (Figure 7). VIN does
not need to be acquired continuously while it is ramping up.
TRACK can be kept low and only when VOUT has reached its
desired voltage is TRACK brought high. At this stage, the
acquisition of VIN begins.
In the example shown, a desired voltage is required on the output
of the pin driver. This voltage is represented by one input to a
comparator. The microcontroller/microprocessor ramps up the
input voltage on VIN through a DAC. TRACK is kept low while
the voltage on VIN ramps up so that VIN is not continually
acquired. When the desired voltage is reached on the output of the
pin driver, the comparator output switches. The µC/µP then
knows what code is required to be input in order to obtain the
desired voltage at the DUT. The TRACK input is now brought
high and the part begins to acquire VIN. BUSY goes low until VIN
has been acquired. When BUSY goes high, the output buffer
is switched from VIN to the output of the DAC.
This feature allows the user to read back the DAC register
code of any of the channels. Readback is useful if the system
has been calibrated and the user wants to know what code in
the DAC corresponds to a desired voltage on VOUT.
INTERFACES
Serial Interface
The SER/PAR pin is tied high to enable the serial interface and
to disable the parallel interface. The serial interface is controlled
by four pins as follows:
SYNC, DIN, SCLK
Standard 3-wire interface pins. The SYNC pin is shared
with the CS function of the parallel interface.
MODES OF OPERATION
DOUT
The AD5533B can be used in three different modes. These modes
are set by two mode bits, the first two bits in the serial word.
The 01 option (DAC Mode) is not available for the AD5533B.
For information on this mode, refer to the AD5532B data sheet.
If you attempt to set up DAC Mode, the AD5533B will enter a
test mode and a 24-clock write will be necessary to clear this.
Data out pin for reading back the contents of the DAC registers.
The data is clocked out on the rising edge of SCLK and is
valid on the falling edge of SCLK.
Mode Bits
There are four different modes of operation as described above.
Cal Bit
When this is high, all 32 channels acquire VIN simultaneously. The
acquisition time is then 45 µs (typ) and accuracy may be reduced.
This bit is set low for normal operation.
Table II. Modes of Operation
Mode Bit 1
Mode Bit 2
Operating Mode
0
0
1
1
0
1
0
1
ISHA Mode
DAC Mode (Not Available)
Acquire and Readback
Readback
Offset_Sel Bit
If this bit is set high, the offset channel is selected and bits
A4–A0 are ignored.
Test Bit
This must be set low for correct operation of the part.
A4–A0 Bit
Used to address any one of the 32 channels (A4 = MSB of
address, A0 = LSB).
–12–
REV. A
AD5533B
MSB
LSB
0
0
CAL
MODE BIT 1
MODE BIT 2
0
OFFSET SEL
A4–A0
TEST BIT
MODE BITS
a. 10-Bit Input Serial Write Word (ISHA Mode)
LSB
MSB
1
0
CAL
0
OFFSET SEL
MSB
A4–A0
LSB
DB1 3 –DB0
TEST BIT
MODE BITS
14-BIT DATA
READ FROM PART AFTER
NEXT FALLING EDGE OF SYNC
(DB13 = MSB OF DAC WORD)
10-BIT
SERIAL WORD
WRITTEN TO PART
b. Input Serial Interface (Acquire and Readback Mode)
LSB
MSB
1
1
0
OFFSET SEL
0
MSB
A4–A0
LSB
DB1 3 –DB0
TEST BIT
MODE BITS
14-BIT DATA
READ FROM PART AFTER
NEXT FALLING EDGE OF SYNC
(DB13 = MSB OF DAC WORD)
10-BIT
SERIAL WORD
WRITTEN TO PART
c. Input Serial Interface (Readback Mode)
Figure 8. Serial Interface Formats
DB13–DB0 Bit
Parallel Interface
These are used in both readback modes to read a 14-bit word
from the addressed DAC register.
The SER/PAR bit is tied low to enable the parallel interface and
disable the serial interface. The parallel interface is controlled
by nine pins as follows:
The serial interface is designed to allow easy interfacing to most
microcontrollers and DSPs, e.g., PIC16C, PIC17C, QSPI™,
SPI™, DSP56000, TMS320, and ADSP-21xx, without the
need for any glue logic. When interfacing to the 8051, the
SCLK must be inverted. The Microprocessor/Microcontroller
Interface section explains how to interface to some popular
DSPs and microcontrollers.
Figures 3 and 4 show the timing diagram for a serial read and
write to the AD5533B. The serial interface works with both a
continuous and a noncontinuous serial clock. The first falling
edge of SYNC resets a counter that counts the number of serial
clocks to ensure the correct number of bits are shifted in and out
of the serial shift registers. Any further edges on SYNC are ignored
until the correct number of bits are shifted in or out. Once the
correct number of bits have been shifted in or out, the SCLK is
ignored. In order for another serial transfer to take place, the
counter must be reset by the falling edge of SYNC. In readback,
the first rising SCLK edge after the falling edge of SYNC causes
DOUT to leave its high impedance state and data is clocked out
onto the DOUT line and also on subsequent SCLK rising edges.
The DOUT pin goes back into a high impedance state on the falling
edge of the 14th SCLK. Data on the DIN line is latched in on the
first SCLK falling edge after the falling edge of the SYNC signal
and on subsequent SCLK falling edges. The serial interface will
not shift data in or out until it receives the falling edge of the
SYNC signal.
CS
Active low package select pin. This pin is shared with the
SYNC function for the serial interface.
WR
Active low write pin. The values on the address pins are
latched on a rising edge of WR.
A4–A0
Five address pins (A4 = MSB of address, A0 = LSB). These
are used to address the relevant channel (out of a possible 32).
Offset_Sel
Offset select pin. This has the same function as the Offset_Sel
bit in the serial interface. When it is high, the offset channel
is addressed and the address on A4–A0 is ignored.
Cal
Same functionality as the Cal bit in the serial interface. When
this pin is high, all 32 channels acquire VIN simultaneously.
MICROPROCESSOR INTERFACING
AD5533B to ADSP-21xx Interface
The ADSP-21xx family of DSPs is easily interfaced to the
AD5533B without the need for extra logic.
A data transfer is initiated by writing a word to the TX register
after the SPORT has been enabled. In a write sequence, data is
clocked out on each rising edge of the DSP’s serial clock and
clocked into the AD5533B on the falling edge of its SCLK. In
*SPI and QSPI are trademarks of Motorola, Inc.
REV. A
–13–
AD5533B
readback, 16 bits of data are clocked out of the AD5533B on
each rising edge of SCLK and clocked into the DSP on the rising
edge of SCLK. DIN is ignored. The valid 14 bits of data will be
centered in the 16-bit RX register when using this configuration.
The SPORT control register should be set up as follows:
TFSW
INVRFS
DTYPE
ISCLK
TFSR
IRFS
ITFS
SLEN
SLEN
= RFSW = 1, Alternate Framing
= INVTFS = 1, Active Low Frame Signal
= 00, Right-Justify Data
= 1, Internal Serial Clock
= RFSR = 1, Frame Every Word
= 0, External Framing Signal
= 1, Internal Framing Signal
= 1001, 10-Bit Data-Words (ISHA Mode Write)
= 1111, 16-Bit Data-Words (Readback Mode)
AD5533B to PIC16C6x/7x
The PIC16C6x synchronous serial port (SSP) is configured as an
SPI Master with the clock polarity bit = 0. This is done by writing
to the Synchronous Serial Port Control Register (SSPCON). See
PIC16/17 Microcontroller User Manual. In this example I/O port
RA1 is being used to pulse SYNC and enable the serial port
of the AD5533B. This microcontroller transfers only eight bits of
data during each serial transfer operation; therefore, two consecutive read/write operations are needed for a 10-bit write and a 14-bit
readback. Figure 11 shows the connection diagram.
PIC16C6x/7x*
AD5533B*
SCLK
SCK/RC3
DOUT
SDO/RC5
Figure 9 shows the connection diagram.
DIN
SYNC
ADSP-2101/
ADSP-2103*
AD5533B*
DOUT
DR
SYNC
TFS
DIN
SCLK
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 11. AD5533B to PIC16C6x/7x Interface
RFS
AD5533B to 8051
DT
The AD5533B requires a clock synchronized to the serial
data. The 8051 serial interface must therefore be operated in
Mode 0. In this mode, serial data enters and exits through RxD
and a shift clock is output on TxD. Figure 12 shows how the 8051
is connected to the AD5533B. Because the AD5533B shifts data
out on the rising edge of the shift clock and latches data in on
the falling edge, the shift clock must be inverted. The AD5533B
requires its data with the MSB first. Since the 8051 outputs
the LSB first, the transmit routine must take this into account.
SCLK
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 9. AD5533B to ADSP-2101/ADSP-2103 Interface
AD5533B to MC68HC11
The serial peripheral interface (SPI) on the MC68HC11 is configured for master mode (MSTR = 1), clock polarity bit (CPOL) = 0
and the clock phase bit (CPHA) = 1. The SPI is configured by
writing to the SPI control register (SPCR)— see 68HC11 User
Manual. SCK of the 68HC11 drives the SCLK of the AD5533B,
the MOSI output drives the serial data line (DIN) of the AD5533B,
and the MISO input is driven from DOUT. The SYNC signal is
derived from a port line (PC7). When data is being transmitted to
the AD5533B, the SYNC line is taken low (PC7). Data appearing on the MOSI output is valid on the falling edge of SCK.
Serial data from the 68HC11 is transmitted in 8-bit bytes with
only eight falling clock edges occurring in the transmit cycle.
Data is transmitted MSB first. In order to transmit 10 data bits
in ISHA mode it is important to left-justify the data in the SPDR
register. PC7 must be pulled low to start a transfer. It is taken
high and pulled low again before any further read/write cycles
can take place. A connection diagram is shown in Figure 10.
MC68HC11*
AD5533B*
DOUT
MISO
SYNC
PC7
SCLK
SCK
DIN
SDI/RC4
RA1
MOSI
*ADDITIONAL PINS OMITTED FOR CLARITY
8051*
AD5533B*
SCLK
TXD
DOUT
RXD
DIN
SYNC
P1.1
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 12. AD5533B to 8051 Interface
APPLICATION CIRCUITS
AD5533B in a Typical ATE System
The AD5533B infinite sample-and-hold is ideally suited for use
in automatic test equipment. Several ISHAs are required to
control pin drivers, comparators, active loads, and signal timing.
Traditionally, sample-and-hold devices with droop were used in
these applications. These required refreshing to prevent the voltage
from drifting.
The AD5533B has several advantages: no refreshing is required,
there is no droop, pedestal error is eliminated, and there is no
need for extra filtering to remove glitches. Overall, a higher level
of integration is achieved in a smaller area. See Figure 13.
Figure 10. AD5533B to MC68HC11 Interface
–14–
REV. A
AD5533B
PARAMETRIC
MEASUREMENT SYSTEM BUS
UNIT
ISHA
ISHA
ACTIVE
LOAD
ISHA
STORED
DATA
AND INHIBIT
PATTERN
DRIVER
ISHA
FORMATTER
DUT
ISHA
PERIOD
GENERATION
AND
DELAY
TIMING
ISHA
COMPARE
REGISTER
ISHA
COMPARATOR
ISHAs
SYSTEM BUS
Figure 13. AD5533B in an ATE System
Typical Application Circuit
The AD5533B can be used to set up voltage levels on 32 channels as
shown in the circuit below. An AD780 provides the 3 V reference
for the AD5533B, and for the AD5541 16-bit DAC. A simple 3-wire
serial interface is used to write to the AD5541. Because the AD5541
has an output resistance of 6.25 kΩ (typ), the time taken to charge/
discharge the capacitance at the VIN pin is significant. Thus an
AD820 is used to buffer the DAC output. Note that it is important
to minimize noise on VIN and REFIN when laying out this circuit.
AVCC
AVCC DVCC
VSS
VDD
CS
DIN
SCLK
AD5541*
AD820
VIN
AD5533B*
REF
OFFS_IN
OFFS_OUT
REFIN
AD780*
VOUT
SCLK DIN
SYNC
VOUT 0–31
POWER SUPPLY DECOUPLING
In any circuit where accuracy is important, careful consideration
of the power supply and ground return layout helps to ensure
the rated performance. The printed circuit board on which the
AD5533B is mounted should be designed so that the analog
and digital sections are separated and confined to certain areas
of the board. If the AD5533B is in a system where multiple
devices require an AGND-to-DGND connection, the connection
should be made at one point only. The star ground point should
be established as close as possible to the device. For supplies with
multiple pins (VSS, VDD, AVCC) it is recommended to tie those
pins together. The AD5533B should have ample supply bypassing of 10 µF in parallel with 0.1 µF on each supply located as
close to the package as possible, ideally right up against the device.
The 10 µF capacitors are the tantalum bead type. The 0.1 µF
capacitor should have low effective series resistance (ESR) and
effective series inductance (ESI), like the common ceramic types
that provide a low impedance path to ground at high frequencies,
to handle transient currents due to internal logic switching.
The power supply lines of the AD5533B should use as large a trace
as possible to provide low impedance paths and reduce the effects
of glitches on the power supply line. Fast switching signals such
as clocks should be shielded with digital ground to avoid radiating
noise to other parts of the board, and should never be run near
the reference inputs. A ground line routed between the DIN and
SCLK lines will help reduce crosstalk between them (not required
on a multilayer board as there will be a separate ground plane,
but separating the lines will help). It is essential to minimize
noise on VIN and REFIN lines.
Note it is essential to minimize noise on VIN and REFIN lines.
Particularly for optimum ISHA performance, the VIN line must
be kept noise-free. Depending on the noise performance of the
board, a noise filtering capacitor may be required on the VIN line.
If this capacitor is necessary, then for optimum throughput it may
be necessary to buffer the source that is driving VIN. Avoid crossover of digital and analog signals. Traces on opposite sides of the
board should run at right angles to each other. This reduces the
effects of feedthrough through the board. A microstrip technique is
by far the best, but not always possible with a double-sided board.
In this technique, the component side of the board is dedicated
to ground plane while signal traces are placed on the solder side.
As is the case for all thin packages, care must be taken to avoid
flexing the CSPBGA package and to avoid a point load on the
surface of this package during the assembly process.
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 14. Typical Application Circuit
REV. A
–15–
AD5533B
OUTLINE DIMENSIONS
74-Lead Chip Scale Ball Grid Array [CSPBGA]
(BC-74)
Dimensions shown in millimeters
11 10 9 8 7 6 5 4 3 2 1
A1
TOP VIEW
C02715–0–9/02(A)
A1 CORNER
INDEX AREA
12.00 BSC
SQ
1.00
BSC
BOT TOM
VIEW
A
B
C
D
E
F
G
H
J
K
L
10.00 BSC
SQ
1.00 BSC
1.70
MAX
DETAIL A
DETAIL A
0.30 MIN
0.20 MAX
COPLANARITY
0.70
SEATING
0.60
PLANE
0.50
BALL DIAMETER
COMPLIANT TO JEDEC STANDARDS MO-192ABD-1
Revision History
Location
Page
9/02—Data Sheet changed from REV. 0 to REV. A.
Term LFBGA updated to CSPBGA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Global
Replaced FUNCTIONAL BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Additions to SERIAL INTERFACE Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Replaced Figure 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Changes to ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Additions to POWER SUPPLY DECOUPLING section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
PRINTED IN U.S.A.
Updated BC-74 package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
–16–
REV. A