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5.4 EVAL6206PD
An evaluation board has been pr oduced to help the evaluation of the devic e in PowerSO pac kage. It implem ents
a typical application with several added components. Figure 48 shows the electrical sc hematic of the board; in
the table below the part list is reported.
CN1, CN2, CN3, CN4 2-poles connector JP2 to JP5 2-pin jumper
CN5 34-poles connector R1 750Ω 0.6W resistor
C1 220nF/100V Ceramic or Polyester capacitor R2, R3, R26 10kΩ resistor
C2 220nF/100V Ceramic or Polyester capacitor R4, R5 4.7kΩ resisto r
C3 100µF/63V capacitor R6, R7 50kΩ trimmer
C4 10nF/100V Ceramic capacitor R8, R9, R10, R11 0.4Ω 1W resistor
C5, C8, C10 10µF/16V Capacitor R12, R19 20kΩ resistor
C6, C7 100 nF Capac itor R13, R14, R17, R20 2.2kΩ resisto r
C9, C13 68nF Capacitor R15, R18 750Ω resistor
C11 100nF Capacitor R16, R22 5kΩ trimmer
C12, C15 470pF Capacitor R23, R21 1kΩ resistor
C14 2.2nF Capacitor R24 12kΩ resistor
D1 Bat46SW Diodes R25 50kΩ trimmer
D2 BZX79C5V1 5.1V Zener Diode U1 L6205N
JP1 3-pin jumper U2 L6506
The Eval uation Board provides exter nal connectors for the supply voltage, an external 5V reference for the logi c
inputs, four outputs for the motor and a 34-pin connector to control the main functions of the board through an
external
µ
C board or the PractiS PIN tool. The board also accomodate the L6506 PWM current controller. R25
sets the PWM operating frequen cy. If the L6506 does not need to be used , simply connect the two V
REF
inputs
to a voltage high enough to keep current control inactive.
The Pr actiSPIN tool is composed of a graphic inter face software running on a PC that connects with the hard-
ware based on the ST7 µC, w hich contains an upgradeable fir mware. This tool allows a fast and easy eval uation
of the PowerSPIN family devices, givi ng the ability of driving DC, BLD C and St epper motors, depending on the
target device. The PractiSPIN
connected to the EVAL6206PD can drive DC motors and inductive loads, allow-
ing output voltage and current settings
The PC-so ftware also prov ides a Power Di ssipa tion and Thermal A nalysi s secti on, intended to help a fas t eval-
uation of the device, package and dissipating copper area required by the user’s application, and to be a good
starting point designing an application (from the power dissipation and thermal point of view).
Running the evaluation board in stand-alone mode, instead, R16 and R22 set the r eference volta ge separately
for the two bridges, while R14, C9 and R20, C 13 are low-pass filters to provide an external reference voltage
by a P WM output of a
µ
C (see also the Micr oste pping sec tion). U sing e xternal V
REF
inputs R12, R16, R19, R22
should be disconnected, unless the Pr actiSPIN ST7 evaluation board is used. This board, in fact, is provided
with an offset cancellation circuitry trimmable through a potentiometer (see PractiSPIN documentation).
Closing JP4 and JP5, R6 and R7 allow adjusting the Over Cur rent Detection threshold separately for the two
full br idges. Leaving JP4 and J P5 opened, the OCD threshold can be pr ogrammed providing r eference voltages
at the bottom of R 6 and R7, through pins 27 and 29 of CN5. R13, R15, C8, R17, R 18, C10 provide low-pass
filtering to obtain these reference voltages from an external PWM output of a µC.
Closing JP2 and JP3 allows Over Current Protection to work, connecting each
EN
pin to the cor res ponding
OCD
pin.
The 5V voltage for logic inputs and for references (V
refA
and V
refB
) is obtained from R1, D2. Depending on the
supply voltage, the value of resistor R1 should be changed in order to ensure a correct biasing of D2.
The jumper JP1 allows choosing the 5V voltage from the inter nal zener diode network or pin 11 of CN5 (for ex-
ample an external µC board can provide 5V to the evaluation board). Also CN2 connector can be used to pro-
vide an external 5V voltage to the board (in that case R1, D2 should be disconnected). C N2, or pin 1 of CN5,
can also be used to provide a 5V voltag e to external c ircuits (as, for example, the PractiS PIN ST7 board) . In thi s