Edge6420
HIGH-PERFORMANCE PRODUCTS – ATE
Application Information (continued)
2.5V
+
+ 5V
0V
+ 15.5V
AVCC
+ 5V
–5V
0V
0V
–
AGND
VEE
AGND
DVDD
DGND
VREF
SGND
AVDD
VOUT_CH0_0
Loading
VOUT_CH0_1
Requirement:
10 nF to 100 nF
VOUT_CH0_2
.
.
.
DAC
Voltage
Outputs
.
Note: All unused
voltage outputs must have
an external capacitor
attached (between
.
10 nF and 100 nF).
.
VOUT_CH0_8
VOUT_CH0_9
VOUT_CH0_10
Edge6420
Loading
Requirement:
10 nF to 100 nF
IOUT_CH0_1
Loading
Requirement:
1 nF (see below)
.
.
.
DAC
Current
Outputs
.
.
.
IOUT_CH0_4
Loading
Requirement:
1 nF (see below)
I
I
I
I
I
I
I
I
I
I
I
REF_F
REF
REF
REF
REF
REF
REF
REF
REF
REF
REF_E
For Group B
DACs
For Group C
DACs
For Group D
DACs
For Group A
DACs
AGND
Gain and
Gain and
Gain and
Gain and
Offset Control
Offset Control
Offset Control
Offset Control
The Selection of
R_MASTER
Establishes I
REF
Figure 7. Required External Resistors and Components
Loading Requirements
Caution on Exceeding Compliance Limits on Current
Output DACs
Voltage Outputs
All voltage outputs (denoted VOUT_CH[0:3]_[0:10]) require
a load capacitance between 10 nF and 100 nF for stability.
Current output DACs (i.e., Group E and F DACs) can exhibit
a “lock-up” condition in situations when the actual voltage
seen at the outputs of these DACs exceeds the compliance
limits in the specification. Care should be taken in the
design of circuits being driven by Group E and F outputs
to ensure compliance limits stated in the specifications
are not exceeded.
Current Outputs
All current outputs require capacitive loading; the amount
of loading needed to ensure stability is dependent on the
impedance that the current outputs of the 6420 drive.
For impedances of 1.3 KΩ to 1.6 KΩ, such as what is
seen at the E720 current inputs (ISK, ISRC, IBIAS, RADJ,
and FADJ), it is recommended that 1 nF be used.
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