Silicon Laboratories TSM1285 User Manual

TSM1285 Demo Board

A 300ksps, Single-supply, 12-Bit Serial-output ADC

FEATURES

 Quick and easy Interface to computer for

evaluation via Nano River Technologies
ViperBoard and USB cable

 Input BNC connection
 On-board +3.3V supply voltage
 External power supply connection available
 Fully Assembled and Tested
 2in x 3in 2-layer circuit board

DESCRIPTION

The demo board for the TSM1285 is a completely
assembled and tested circuit board that can be used
for evaluating the TSM1285. For easy and quick
evaluation of the TSM1285, a Nano River Tech
ViperBoard with an onboard microcontroller and
FPGA for signal processing is available. The
ViperBoard interfaces to any computer via USB port
and a user-friendly Windows OS compatible software
is available for evaluation.

The TSM1285 – a single-supply, single-channel, 12­bit analog-to-digital converter (ADC) - is an alternate
source for the MAX1285 and a higher-speed upgrade
to the MAX1240 and MAX1240 ADCs. The TSM1285
combines a high-bandwidth track-and-hold (T/H), a
high-speed serial digital interface, an internal +2.5V
reference, and low conversion-mode power
consumption. The TSM1285 operates from a single
+2.7V to+3.6V supply and draws less than 2.5mA at
300ksps.

Product data sheet and additional documentation can
be found at www.silabs.com.

Figure 1. TSM1285 Evaluation Board

with Nano River Tech ViperBoard

Figure 2. TSM1285 Evaluation Board

(Top View)

ORDERING INFORMATION

Order Number Description

TSM1285DB

TSDA-VB Nano River Tech ViperBoard

Figure 3. TSM1285 Evaluation Board

(Bottom View)

TSM1285

Demo Board

Page 1

© 2014 Silicon Laboratories, Inc. All rights reserved.

TSM1285 Demo Board

Description

The TSM1285 demo board provides an easy-to-use
scheme for evaluating the TSM1285. The default
configuration of the demo board in conjunction with
the Nano River Technologies ViperBoard is for
operation at a supply voltage of V

The TSM1285 demo board includes a
74ALVC164245 signal level translator in order to
translate signal levels from V
+3.3V signal voltage levels necessary for the
ViperBoard. The TSM1285 and the ViperBoard are
connected via an on-board 34-pin ribbon socket (X1).

A separate power supply can be used to power the
TSM1285 from +2.7V to +3.6V. If evaluating the
TSM1285 demo board without the ViperBoard, a
single power supply is needed. A BNC connector is
available for the input of the TSM1285, AIN, and it is
recommended to use a low-noise signal generator in
order to acquire optimal SNR and THD results. Refer
to Table 1. Figure 6 shows the TSM1285 demo
board schematic, Figure 2 and Figure 3 show a
picture of the top and bottom of the TSM1285 demo
board, respectively. Figure 1 shows a picture of the
TSM1285 demo board with the ViperBoard
connected.

A USB cable is used to interface the ViperBoard to a
PC with Windows Vista 32-bit/Vista 64-bit/XP/7. For
the “Touchstone ADC Evaluation Platform GUI”
user’s manual and for the necessary driver and GUI
installer files needed to successfully evaluate the
TSM1285 with the ViperBoard, please refer to

www.silabs.com.

=+3.3V.

DD

of the TSM1285 to

DD

Quick Start Procedure

Required Equipment

 TSM1285 Demo Board
 Nano River Tech ViperBoard
 USB cable
 Computer with Windows Vista 32-bit/64-bit/XP/7

In order to evaluate the TSM1285, jumper J2 is to be
set to position 1-2. The default configuration for J2 is
1-2. Refer to Figure 6 and Table 1. The default
configuration on the board is for V
following steps are to be performed:

1) Connect the TSM1285 demo board to the
ViperBoard via the 34-pin socket (X1).

2) Set the function generator frequency, amplitude,
and offset to 70kHz, 2.499V
respectively. Then, connect the BNC cable from
the signal generator to the BNC connector AIN on
the TSM1285 demo board. Set the output of the
signal generator to OFF.

3) To run the GUI, go to Start > All Programs >

TouchStoneEvalBoard 2.2.10 > 01 Touchstone
Evaluation App. The GUI should appear and on

the top right hand side, the status should be “PC
disconnected” and “No Type” for demo board
type. Both should be highlighted in red indicating
the ViperBoard and the TSM1285 demo board is
not connected.

4) Connect one side of the supplied USB cable to
the ViperBoard USB connector. Connect the
other side to a USB port on the PC. After
approximately three seconds, the status on the
GUI screen will switch to “PC Connected” and
“TSM1285” indicating the ViperBoard and the
TSM1285 demo board were recognized
successfully by the software. The green LED on
the TSM1285 demo board should be ON and the
green LED on the ViperBoard, D2, should be ON.
Use the default sampling rate of 300kSPS and an
FFT length of 8192.

5) Turn on the signal generator. On the GUI screen,
click on “continuous” in the sampling section, and
monitor the results on the screen. The top plot
shows a samples vs code plot and the bottom
plot is an FFT plot. The SNR and THD values
should be approximately 70dB and –80dB,
respectively. Please refer to Figure 4 for an
example of what the results should look like. In
this case, the SNR and THD values are 69dB and

-85dB, respectively.

= +3.3V. The

DD

, and 1.25V,

PP

 ViperBoard driver and GUI software installed to

PC( refer to “Touchstone ADC Evaluation
Platform GUI” user’s manual)

 Low-noise Signal Generator Stanford Research

Systems Model DS360 or better w/ BNC cable

Page 2 TSM1285-EVB Rev. 1.0

Additional Functions

6) As shown in the TSM1285 ADC section, a
shutdown control function is available. If the
“shutdown” button is selected when sampling in
continuous mode, the TSM1285 will be in
shutdown mode and no additional conversions

will occur. To de-assert the shutdown function,
press the button again and the conversions will
resume. Figure 5 shows what the GUI looks like
when the shutdown control function is enabled.

7) A shutdown between conversions function is
available by selecting the “Shutdown between
conversions” box. Refer to Figure 4. When
performing a continuous conversion, press the
“shutdown” button and then select the
“Shutdown between conversions” box. The
samples vs code and the FFT plot will update
after every conversion.

Sampling section

TSM1285 Demo Board

8) To perform a single conversion, press the “single”
button in the sampling section.

9) For details on the evaluation platform GUI, refer
to the “Touchstone ADC Evaluation Platform GUI”
user’s manual at: www.silabs.com.

TSM1285 ADC section

Samples vs Code plot

FFT plot

.

TSM1285-EVB Rev. 1.0 Page 3

Figure 4. TSM1285 Response with GUI