Data Sheet

AD5522

Rev. E | Page 49 of 64

Bit

Bit Name

Description

14

MEAS1

The MEAS1 and MEAS0 bits specify the required measure mode, allowing the MEASOUTx line to be disabled,

connected to the temperature sensor, or enabled for measurement of current or voltage.

13

MEAS0

MEAS1

MEAS0

Action

0

0

0

1

1

0

MEASOUTx is connected to the temperature sensor

1

1

MEASOUTx is high-Z (SW12 open)

12

FIN

This bit sets the status of the force input (FIN) amplifier.

0 = input of the force amplifier switched to GND.

1 = input of the force amplifier connected to the FIN DAC output.

11

SF0

The SF0 and SS0 bits specify the switching of system force and sense lines to the force and sense paths at the

DUT. The channel to which the system force and system sense lines are connected is set by the PMU3 to PMU0

bits. For correct operation, only one PMU channel should be connected to the SYS_FORCE and SYS_SENSE

paths at any one time.

10

SS0

SF0

SS0

Action

0

0

SYS_FORCE and SYS_SENSE are high-Z for the selected channel

0

1

SYS_FORCE is high-Z and SYS_SENSE is connected to MEASVHx for the selected channels

1

0

SYS_FORCE is connected to FOHx and SYS_SENSE is high-Z for the selected channel

1

1

SYS_FORCE is connected to FOHx and SYS_SENSE is connected to MEASVHx for the selected

channel

9

CL

Per-PMU current or voltage clamp enable bit. A logic high enables the clamp function for the selected PMU. The

clamp enable function is also available in the system control register. This dual functionality allows flexible

enabling or disabling of this function. When reading back information about the status of the clamp enable

function on a per-channel basis, 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.

8

CPOLH

Comparator output enable bit. By default, the comparator outputs are high-Z on power-on. A logic high enables

the comparator output for the selected PMU. The comparator function CPBIASEN (Bit 13 in the system control

register), must be enabled. The comparator output enable function is also available in the system control register.

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.

7

Compare

V/I

A logic high selects the compare voltage function; a logic low selects the compare current function.

6

Clear

To clear or reset a latched alarm bit and pin (temperature, guard, or clamp), write a 1 to this bit. This bit applies

to latched alarm conditions (clamp and guard) on all four PMU channels.

5

Unused

Unused bits. Set to 0.

4

3

2

1

0 (LSB)

1

Writing 101 in Bit 17 to Bit 15 disables the always on mode for the external current range buffer. Use with FV mode (FORCE1 = FORCE0 = 0) only. To complete the

disabling of the always on mode, the PMU channel is placed into high-Z mode and the external current range buffer is returned to its default operation (off).

2

Writing 110 in Bit 17 to Bit 15 places the external current range buffer into always on mode. In this mode, the buffer is always active with no regard to the selected current

range. The always on mode is intended for use where an external high current stage is being used for a current drive in excess of ±80 mA; having the internal stage

always on should help to eliminate timing concerns when transitioning between this current range and other ranges. When first enabling the always on mode, use it in

conjunction with FV mode (FORCE1 = FORCE0 = 0); the device now enables the external current range buffer. The 110 code also places the device into high-Z mode

(necessary to complete the enabling function). To return to an FV or FI operating mode, select the appropriate mode and current range. The external range sense

resistor is connected to an MI circuit only when the external current range address is selected (C2 to C0 are set to 100). The default operation at power-on is disabled

(or off).