AD5522JSVUZ Analog Devices Inc, AD5522JSVUZ Datasheet - Page 46

• Manufacturer Part Number: AD5522JSVUZ
• Description: Quad PPMU With DACs And LVDS/SPI
• Manufacturer: Analog Devices Inc

Specifications of AD5522JSVUZ

• Design Resources: Parametric Measurement Unit and Supporting Components for PAD Appls Using AD5522 and AD7685 (CN0104)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AD5522
WRITE SYSTEM CONTROL REGISTER
The system control register is accessed when the PMU channel
address bits (PMU3 to PMU0) and the mode bits (MODE1 and
MODE0) are all 0s. This register allows quick setup of various
Table 21. System Control Register Bits—Bit B28 to Bit B15
B28
RD/WR
Table 22. System Control Register Bits—Bit B14 to Bit B0
B14
CPOLH0
1
Table 23. System Control Register Functions
Bit
28 (MSB)
27
26
25
24
23
22
System Control Register-Specific Bits
21
20
19
18
17
16
15
14
13
12
11
10
9
8
Bit B1 and Bit B0 are unused data bits.
B13
CPBIASEN
B27
PMU3
Bit Name
RD/WR
PMU3
PMU2
PMU1
PMU0
MODE1
MODE0
CL3
CL2
CL1
CL0
CPOLH3
CPOLH2
CPOLH1
CPOLH0
CPBIASEN
DUTGND/CH
GUARD ALM
CLAMP ALM
INT10K
Guard EN
B26
PMU2
B12
DUTGND/CH
Description
When low, a write function takes place to the selected register; setting the RD/WR bit high initiates a readback
sequence of the PMU, alarm status, comparator status, system control, or DAC register, as determined by the
address bits.
Set Bit PMU3 to Bit PMU0 to 0 to address the system control register.
Set the MODE1 and MODE0 bits to 0 to address the system control register.
Current or voltage clamp enable. Bit CL3 to Bit CL0 enable and disable the current or voltage clamp function per
channel (0 = disable; 1 = enable). The clamp enable function is also available in the PMU register on a per-
channel basis. This dual functionality allows flexible enabling or disabling of this function. When reading back
information about the status of the clamp enable function, the data that was most recently written to the clamp
register is available in the readback word from either the PMU register or the system control register.
Comparator output enable. By default, the comparator outputs are high-Z on power-on. A 1 in each bit position
enables the comparator output for the selected channel. Bit 13 (CPBIASEN) must be enabled to power on the
comparator functions. The comparator enable function is also available in the PMU register on a per-channel
basis. This dual functionality allows flexible enabling or disabling of this function. When reading back information
about the status of the comparator enable function, the data that was most recently written to the comparator
status register is available in the readback word from either the PMU register or the system control register.
Comparator enable. By default, the comparators are powered down when the device is powered on. To enable
the comparator function for all channels, write a 1 to this bit. A 0 disables the comparators and shuts them
down. The comparator output enable bits (CPOLHx, Bit 17 to Bit 14) allow the user to turn on each comparator
output individually, enabling busing of comparator outputs.
DUTGND per channel enable. The GUARDINx/DUTGNDx pins are shared pins that can be configured to enable a
DUTGND per PMU channel or a guard input per PMU channel. Setting this bit to 1 enables DUTGND per
channel. In this mode, the pin functions as a DUTGND pin on a per-channel basis. The guard inputs are
disconnected from this pin and instead are connected directly to the MEASVHx line by an internal connection.
The default power-on condition is GUARDINx.
Clamp and guard alarm functions share one open-drain alarm pin (CGALM). By default, the CGALM pin is
disabled. The guard ALM and clamp ALM bits allow the user to choose whether clamp alarm information, guard
alarm information, or both sets of alarm information are flagged by the CGALM pin. Set high to enable either
alarm function.
Internal sense short. Setting this bit high allows the user to connect an internal sense short resistor of 10 kΩ
(4 kΩ + 2 kΩ switch + 4 kΩ) between the FOHx and the MEASVHx lines (SW7 is closed). Setting this bit high also
closes SW15, allowing the user to connect another 10 kΩ resistor between DUTGNDx and AGND.
Guard enable. The guard amplifier is disabled on power-on; to enable the guard amplifier, set this bit to 1. If the
guard function is not in use, disabling it saves power (typically 400 μA per channel).
B25
PMU1
B11
Guard
ALM
B24
PMU0
B10
Clamp
ALM
B23
MODE1
B9
INT10K
Rev. D | Page 46 of 64
B22
MODE0
B8
Guard
EN
B21
CL3
functions in the device. The system control register operates on
a per-device basis.
B7
GAIN1
B20
CL2
B6
GAIN0
CL1
B19
B5
TMP
enable
B18
CL0
B4
TMP1
B17
CPOLH3
B3
TMP0
CPOLH2
B16
B2
Latched
B15
CPOLH1
B1
0
1
B0
0
1