Instruction Manual

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dc2369af

DEMO MANUAL DC2369A

INTRODUCTION

Low Power

Wireless Current Sense

The DC2369A demo circuit is a reference design that

implements a wireless current sense solution using

Linear Technology’s low power integrated cir

cuits. The only

external connection needed is the current to be measured,

allowing this circuit to be inserted at any voltage level or

isolation level.

The design combines components for current measure

ment, power management and wireless mesh networking.

A micro-power zero-drift op amp (

2063) amplifies

the voltage across a sense resistor. A 16-bit SAR ADC

and precision reference (

AD7988 and LT

6656) digitize

the reading. A SmartMesh IP™ wireless radio module

L, LT, LTC, LTM, Linear Technology, SmartMesh and the Linear logo are registered trademarks

and SmartMesh IP is a trademark of Analog Devices, Inc. All other trademarks are the property

of their respective owners.

(

LTP5901-IPM) runs the application, provides the wire-

less mesh connectivity and communicates with a central

network manager

. A switching power supply (

LTC3335)

counts the cumulative charge drawn from the included

battery while also regulating the output voltage for the rest

of the application. Table 1 shows featured components

used along with their function.

Design files for this circuit board are available at

http://www.linear.com/demo/DC2369A

Table 1

LTC PART NUMBER FUNCTION BENEFITS

LTC2063 2µA Zero-Drift Op Amp Measures Small Voltage Drop Across Sense Resistor to Measure Current

AD7988-1 100ksps Ultra Low Power 16-Bit SAR ADC Digitizes Measurement from Op Amp While Consuming <1µA at Low Sample Rate

LT6656-3 1µA Precision Voltage Reference <10ppm/°C Reference for Stable ADC Measurement. Provides Low Noise Supply

for Op Amp

LTP5901-IPM SmartMesh IP Mote Module Automatically Forms Low Power, Reliable Wireless Network. Built-In

Microprocessor Manages ADC and Power Supplies

LTC3335 Nanopower Buck-Boost DC/DC with

Integrated Coulomb Counter

Measures Total Charge Drawn from Battery. Regulates Output Supply for Rest of

Application

Downloaded from Arrow.com.

Summary of content (10 pages)

PAGE 1
DEMO MANUAL DC2369A Low Power Wireless Current Sense INTRODUCTION The DC2369A demo circuit is a reference design that implements a wireless current sense solution using Linear Technology’s low power integrated circuits. The only external connection needed is the current to be measured, allowing this circuit to be inserted at any voltage level or isolation level. The design combines components for current measurement, power management and wireless mesh networking.
PAGE 2
DEMO MANUAL DC2369A DC2369A CONNECTIONS AND JUMPERS 1. Set the slide switch SW1 to ON to power on the circuit. DC2369A is powered from its included two AAA batteries and therefore does not need an external power supply. The slide switch asserts the enable pin of the LTC3335. You may verify correct operation of the power supplies by measuring (on the back of the circuit board) that VDD – GND = 3.3V and VREF – GND = 3.0V. 2. The only external connection needed to the DC2369A is for the current to be measured.
PAGE 3
DEMO MANUAL DC2369A INSTALL THE DC2369A GUI For demonstration purposes, a small sample Python based graphical user interface (GUI) application was designed to subscribe to all incoming DC2369A device messages and display the data. For more information on programming to the manager software application programming interface (API), refer to the SmartMesh IP Embedded Manager API Guide. 1.
PAGE 4
DEMO MANUAL DC2369A FORM THE WIRELESS NETWORK 6. In the port name field, enter the COM port that corresponds to the Manager API. This is typically the last of the four COM ports added. Then click the connect button. The GUI window will change as shown in Figure 4 if connection is successful. If you don’t know what the Manager API COM port is, refer to the SmartMesh IP Tools Guide for instructions. 7.
PAGE 5
DEMO MANUAL DC2369A FORM THE WIRELESS NETWORK Figure 5. DC2369A GUI Showing Example Data for a Mote SOURCE CODE 1. DC2369A has been preprogrammed with custom firmware that runs on the internal microprocessor of the LTP5901-IPM. This firmware has been created in the SmartMesh IP On-Chip SDK (OCSDK), and can be accessed on Github. 2. The DC2369A GUI has been created in Python, built on the SmartMesh® SDK. The source code can be accessed on Github. dc2369af 5 Downloaded from Arrow.com.
PAGE 6
DEMO MANUAL DC2369A PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER BATTERY HOLDER, 2CELL AAA, PC MNT KEYSTONE, 2468K-ND Required Circuit Components 1 1 BTH1 2 1 C1 CAP, CHIP, X5R, 22µF, 20%, 6.3V, 1206 SAMSUNG, CL31A226MQHNNNE 3 1 C2 CAP, CHIP, X5R, 150µF, 20%, 6.
PAGE 7
4 3 2 1 REVISION HISTORY ECO REV - 5 DESCRIPTION J1 HDR_5x2_FTSH MOLEX, 87831-1020 IPCS_SSn IPCS_SCK IPCS_MISO VSUP UARTC0_TX D 1 3 5 7 9 TCK TMS UARTC0_RX 1 3 5 7 9 2 4 6 8 10 D TDO TDI VSUP R42 LTP5901-IPM R8 VSUP 100k R10 DP0 IRQ 31 32 33 34 R1 100k R41 R2 100k CONV DNP R3 0 VSUP VOUT 3.
PAGE 8
3 2 1 L1 100uH LPS4018-104MLC D 1 BAT ON + I BTH1 + 3 C1 22uF 1206 6.3V 20% SW1 7 2 2-AAA battery holder 2468K-ND 16 1 OFF VDD D PBAT PVOUT BAT VOUT 11 VOUT 3.3V (or 3.6V) 12 C2 150uF 1210 6.3V 20% TP1 E2 GND EN PGOOD SPDT OS102011MS2QN1 18 PGOOD E3 BAT BAT R16 2 I AAA Lithium 8 E1 SW2 9 SW1 LTC3335EUD 10 U1 3.6V DNP C C R17 SCL SDA DVCC OUT2 OUT1 OUT0 3 4 5 R19 4.
PAGE 9
3 2 4 VOUT GND 2 R29 R30 2.00Meg 0805 VREF 2.00Meg 0805 R32 2.49Meg I_IN+ LT6656-3 C11 0.1uF C5 1uF 0603 10V SHDNB C R31 DNP VIN- R37 14.0k JP2 3 SHDNB OUT 4 -IN TP4 C6 0.1uF 10V C REFVCC R36 10k U3 LTC2063 U4 C7 10uF 0805 10V 1 2 3 4 R38 5 2.00Meg REF VIO VDD SDI INP SCK INM SDO GND AD7988 0805 INT EXT J3 14.0k INT EXT E7 I_IN- VIN+ +IN 2 RSENSE 0.01 CSSH2728 E6 1 V- JP1 V+ R33 5 6 J2 VREF C4 22uF 1206 10V 7 U2 GND R28 2.
PAGE 10
DEMO MANUAL DC2369A DEMONSTRATION BOARD IMPORTANT NOTICE Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions: This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use.