TE0630 is provided with a Dip switch S1B.
Dip switch S1B conditions the value of signal PS_EN.
In this way, S1B conditionally/unconditionally enables the power rails 1.2 V, 1.5 V and 2.5 V power rails.
Note. DNP: Do Not Populate aka Do Not Solder the Component associated to DNP label.
Figure 33: Dip switch S1B (angle view).
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When S1B is turned off (open) (FX2 PON position), the 1.2 V, 1.5 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 power rails 1.2 V, 1.5 V and 2.5 V power rails and starts up the module in low-power mode. After enumeration, the USB microcontroller firmware enables (switches on) the power rails 1.2 V, 1.5 V and 2.5 V power rails on, if enough current is available from the USB bus.
When S1B is turned on (closed) (PON position), the power rails 1.2 V, 1.5 V and 2.5 V power rails are always enabled (switched on).
S1B position | Default position | Effect on 1.2 V, 1.5 V and and 2.5 V rails |
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FX2 PON (off, open) | Power rails 1.2 V, 1.5 V and 2.5 V rails controlled by USB FX2 microcontroller (signal FX2_PS_EN) PS_EN = FX2_PS_EN = 1 or 0 | |
PON (on, closed) | Power rails 1.2 V, 1.2 5 V and 2.5 V rails always enabled (PS_EN = 1) PS_EN ≠ FX_PS_EN = 1 or 0 |
Table 14: Dip switch S1B settings overview (power rails 1.2 V, 1.5V 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
Port D Pin | Alternate Function | Alternate Function is Selected By... | Alternate Function is Described in... |
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PD[7:0] | FD[15:8] | IFCFG1 = 1 and any WORDWIIDE bit = 1 | Slave FIFOs chapter 9 on page 99 |
Table from EZ-USB(R) Technical Reference Manual (EZ-USB_TRM.pdf).
Power-rail 3.3V is not controlled by signal PS_EN and is unconditionally enabled.
Figure 37: Power rails 3.3V could not be enabled/disabled by signal PS_EN.
According to the corresponding assembly option, power rail VCCCIO0 can depend or not on the power rail 2.5V power rail.
Figure 37: example of VCCIO0 assembly not dependent on 2.5V power rail. The other way is also possible.
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Full power operation (PS_EN = 1): when Dip switch S1B 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 V, 1.5V 5 V and 12.2V 5 V are unconditionally enabled.
Figure 39: S1B on position PON (PS_EN ≠ FX2_PS_EN = x; PS_EN = high ).
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