MAX3942 Evaluation Kit

_____________________________________________________________________ Quick Start

1) If the data is to be latched, place shunt on JP8

(RTEN) to enable the clock inputs. Otherwise, leave it

open.

2) Install a jumper on JP2.

3) Install a jumper on the right side of JP3. This allows

adjustment of MODSET using R3.

4) To use the pulse-width control (PWC) install a jumper

on the lower two pins of JP1. To disable PWC place a

jumper on the top two pins of JP1.

5) Ensure that a jumper is not installed on JP9 (MODEN)

and enable modulation.

6) Connect a differential signal source to J34 (DATA+)

and J33 (DATA-). Refer to the MAX3942 data sheet to

determine voltage levels.

7) If the latch is enabled, apply a differential clock signal

to J2 (CLK+) and J31 (CLK-). Refer to the MAX3942

data sheet to determine voltage levels.

8)

Connect a high-bandwidth oscilloscope, such as the

Tektronix CSA8000 with 80E01 sampling heads, to

J16 (OUT+) and J6 (OUT-).

9)

High-quality SMA attenuators (14dB or 20dB) are

required to reduce the signal level for compatibility

with the most sampling heads. The attenuators should

be connected directly to the output SMA connectors

on the EV kit to minimize transmission line reflections.

10) Attach a -5.2V power supply to J10 (GND) and J11

the board.

11) Adjust R3 (MODSET) until the desired modulation

swing is achieved.

12) Adjust R1 (PWC) until the desired pulse width is

achieved (if PWC is enabled, see step 5).

13) If desired, place a shunt on JP10 (PLRT) to invert the

output data polarity.

_______________________________________ Adjustments and Control Descriptions

COMPONENT

NAME

FUNCTION

JP1

PWC

This jumper enables/disables the pulse-width-control circuitry. Place a shunt on

the top two pins to disable the PWC circuitry. Place a shunt on the bottom two pins

to enable the PWC circuitry.

JP3

MODSET

potentiometer to the MAX3942. Place a jumper on the left-hand side of this jumper

to connect the MODSET pin to the SMB connector for AC testing.

JP8

RTEN

Enables/disables data retiming. Shunt to enable data retiming. Remove shunt for

direct data transmission.

JP9

MODEN

Enables/disables modulation output. Shunt to disable switching of the data output.

When shunted, the output goes to the absorbtive (logic 0) state. Remove shunt to

enable modulation.

JP10

PLRT

Enables/disables the polarity inversion function. Shunt to invert the polarity of the

normal operation.

R1

Adjusts the EAM pulse width. Turn the potentiometer screw counter-clockwise to

increase the logic 1 width.

R3

Adjusts the EAM modulation current. Turn the potentiometer screw clockwise to

increase the modulation amplitude (decrease the resistance of MODSET to GND).