Datasheet

AD5522 Data Sheet
Rev. E | Page 54 of 64
READBACK OF SYSTEM CONTROL REGISTER
The system control register readback function is a 24-bit word. Mode and system control register data bits are shown in Table 31.
Table 31. System Control Register Readback
Bit Bit Name Description
23 (MSB) MODE1 Set the MODE1 and MODE0 bits to 0 to address the system control register.
22 MODE0
System Control Register-Specific Readback Bits
21 CL3 Read back the status of the individual current clamp enable bits.
0 = clamp is disabled.
1 = clamp is enabled.
When reading back information about the status of the clamp enable function, the data that was most
recently written to the current clamp register from either the system control register or the PMU register
is available in the readback word.
20 CL2
19 CL1
18 CL0
17 CPOLH3 Read back information about the status of the comparator output enable bits.
1 = PMU comparator output is enabled.
0 = PMU comparator output is disabled.
When reading back information about the status of the comparator output enable function, the data
that was most recently written to the comparator status register from either the system control register
or the PMU register is available in the readback word.
16 CPOLH2
15 CPOLH1
14 CPOLH0
13 CPBIASEN This readback bit indicates the status of the comparator enable function.
1 = comparator function is enabled.
0 = comparator function is disabled.
12 DUTGND/CH DUTGND per channel enable.
1 = DUTGND per channel is enabled.
0 = individual guard inputs are available per channel.
11 GUARD ALM These bits provide information about which of these alarm bits trigger the
CGALM
pin.
1 = guard/clamp alarm is enabled.
0 = guard/clamp alarm is disabled.
10 CLAMP ALM
9 INT10K If this bit is high, the internal 10 kΩ resistor (SW7) is connected between FOHx and MEASVHx, and
between DUTGND and AGND. If this bit is low, SW7 is open.
8 Guard EN Read back the status of the guard amplifiers. If this bit is high, the amplifiers are enabled.
7 GAIN1 Status of the selected MEASOUTx output range. See Table 10 and Table 11.
6 GAIN0
5 TMP ENABLE Read back the status of the thermal shutdown function.
4 TMP1
Bits[5:3] Action
3 TMP0 0XX Thermal shutdown disabled.
100 Thermal shutdown enabled at junction temperature of 130°C (power-on default).
101 Thermal shutdown enabled at junction temperature of 120°C.
110
Thermal shutdown enabled at junction temperature of 110°C.
111 Thermal shutdown enabled at junction temperature of 100°C.
1XX Thermal shutdown enabled.
2 Latched This bit indicates the status of the open-drain alarm outputs,
TMPALM
and
CGALM
.
1 = open-drain alarm outputs are latched.
0 = open-drain alarm outputs are unlatched.
1 Unused
readback bits
Loads with 0s.
0 (LSB)