TE0320 is provided with a slide switch S2.
Slide switch S2 conditions the value of signal PS_EN.
In this way, S2 conditionally/unconditionally enables the 1.2 V and 2.5 V power rails.
Figure 33:
Scroll pdf title | ||
---|---|---|
|
...
...
Scroll pdf title | |
---|---|
|
|
...
Scroll pdf title | ||
---|---|---|
| ||
control.When S2 is turned on (closed, FX2 PON), the power rails 1.2 V and 2.5 V power rails are controlled by the USB (EZ-USB FX2LP USB FX2) microcontroller. At start-up, the USB microcontroller switches off the 1.2 V and 2.5 V power rails and starts up the module in low-power mode. After enumeration, the USB microcontroller firmware switches the 1enables (switches on) power rails 1.2 V and 2.5 V power rails on, if enough current is available from the USB bus.
When S2 is turned off (open, PON), the 1.2 V and 2.5 V power rails are always enabled (switched on).
Warning |
---|
When S2 is turned on (FX2 PON), make sure that no signals are applied to the input pins when power-rails are disabled by the USB microcontroller (at start-up). |
Scroll pdf title | ||||||
---|---|---|---|---|---|---|
| ||||||
|
...
|
...
|
Table 14: Slide switch S2 settings overview (1.2 V and 2.5 V rails only).
To command signal FX2_PS_EN, read the reference firmware code.
IOD = 0x03; // Enable PS_EN and disable PROG_B
OED = 0x03; // Configure PS_EN and PROG as outputs
Scroll pdf title | ||||||||
---|---|---|---|---|---|---|---|---|
| ||||||||
Table from EZ-USB(R) Technical Reference Manual (EZ-USB_TRM.pdf)
|
...
Signal PS_EN enables (1) or disables (0) power rails 1.2
...
V and
...
2.
...
5 V.
...
Scroll pdf title | ||
---|---|---|
|
...
|
...
|
...
|
...
Power-rail 3.3V is not controlled by signal PS_EN and is unconditionally enabled.
...
Scroll pdf title | ||
---|---|---|
|
...
...
...
According to the corresponding assembly option, power rail VCCCIO0 can depend or not on the power rail 2.5V
...
.
Voltage VccIO for bank B0 shall span from 2.5 V to 3.3 V. VccIO can be supplied either externally or internally to the micromodule.
Warning |
---|
Spartan-3 I/Os are not 5 V tolerant. Applying more than the recommended operating voltages at any pin, results in a damaged FPGA (see Xilinx Answer AR#19146). |
Scroll pdf title | |
---|---|
|
|
...
|
...
When slide switch S2 is in the left position ( = FX2 PON : power rails conditionally on depending on signal FX2_PS_EN), signal PS_EN is set to signal FX2_PS_EN (PS_EN = FX2_PS_EN) driven by the EZ-USB FX2LP USB FX2 microcontroller under user control (IOD and OED of fw.c).
...
Scroll pdf title | ||
---|---|---|
|
...
...
Full power operation (PS_EN = 1): when slide switch S2 is in the right position (PON = power rails unconditionally on), signal PS_EN is set to power rail 3.3V. Thus power rails rails 1.2 .5V V and 12.2V 5 V are unconditionally enabled.
Figure 39:
Scroll pdf title | ||
---|---|---|
|
|
| |
.
Table 14 The table below summarizes all switching options implied by slide switch S2 and firmware signal FX2_PS_EN (under the standard assembly option).
Scroll pdf title | ||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ||||||||||||||||||||
(1) R131 |
...
populated / R132 |
...
unpopulated (2) R131 |
...
unpopulated / R132 populated |
Slide switch S2 can be replaced by one resistors in the following cases:
...
Assembly option when resistor R17 not populated and R19 populated is equivalent to slide switch S2 permanently set to PON.
Figure 41: assembly
Scroll pdf title | ||
---|---|---|
|
...
Assembly option when resistor R17 populated and R19 not populated is equivalent to slide switch S2 permanently set to FX2 PON.
Figure 42:
Scroll pdf title | ||
---|---|---|
|
...
...
...
Warning |
---|
Any other assembly options of R17 and R19 are not allowed. |