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dc1785af

DEMO MANUAL DC1785A

QUICK START PROCEDURE

To zoom the graph, left click and drag. To undo any zoom

and re-initiate auto-scroll, double left click anywhere on

the graph.

Tools

There are two tools included in the software package;

both are accessible under the tools menu in the software.

Statistics: The statistics window lists some basic informa-

tion about the gathered values. It gives, mean, standard

deviation, min, max and crest factor. The statistics can be

reset with the reset button.

PWM: The PWM window allows the user to configure the

PWM functionality of the LTC2991. The DC1785A includes

a red LED next to the PWM turret which reflects the duty

cycle of the PWM pin. The pin needs to be enabled in this

window in order for proper functionality to be achieved.

This window also allows the user to set the PWM threshold.

Please see the LTC2991 datasheet for an explanation of

the PWM pin functionality.

HARDWARE SET-UP

Connection to DC590 Serial Controller

J1 is the power and digital interface connector. Connect

to DC590 serial controller with supplied 14-conductor

ribbon cable.

Jumper Settings

V1, V2, V7, V8 – (Default VOLT, VOLT, VOLT, VOLT). These

jumpers can be toggled between VOLT and TEMP. VOLT

connects the corresponding input on the LTC2991 with the

corresponding turret for an external input. TEMP connects

the corresponding input to MMBT (V1 and V2). Please

note that the jumpers should be moved in pairs, V1 and

V2 should both be connected either to VOLT or TEMP and

V7 and V8 should also be both connected to either VOLT

or TEMP. Once set the proper selection should also be

made inside the QuikEval software in the mode selection

box, to reflect any changes made.

VCC – (Default DC590) EXTVCC allows the user to provide

the VCC voltage (2.9V to 5V) to the LTC2991 at turret

EXTVCC while DC590(5V) powers the LTC2991 with 5V

from the DC590. State of VCC can be seen through red

LED D1.

ADR0, ADR1, ADR2 – (Default LOW, LOW, LOW) These

jumpers are used to select the I2C address for the LTC2991.

When used with QuikEval, the correct address should also

be selected from within the software.

Analog Connections

Analog signal connections are made via the row of turret

posts along the edge of the board. Also, when connecting

the board to an existing circuit the exposed ground planes

along the edges of the board may be used to form a solid

connection between grounds.

GND – (8 turrets) These turrets are connected directly to

the internal ground planes.

EXTVCC – This turret allows the user to provide VCC to the

LTC2991. Select VCC jumper accordingly.

V1, V2, V3, V4, V5, V6, V7, V8 – These turrets are used to

provide input voltage to the monitor when the correspond-

ing jumpers are set to the VOLT position.

Digital Connections

PWM – PWM output pin configurable through the QuikEval

software. State of the PWM pin is reflected quantitatively

through the PWM LED at D2.

SDA, SCL – I2C signals brought out to turrets. If DC1785A is

to be run without a DC590 connected or with an alternative

microprocessor, I2C signals can be driven at these points.

If DC590 is not used R4 and R5 (Backside of board) can

be populated with appropriate I2C pull-up values.

GPO – General purpose output pin can be toggled through

QuikEval software.