User`s guide

3.10 dc Power Distribution

Figure 3–7 SROM and Serial Port

srom_dat

srom_oe_l

PLD

srom_clk

srom_clk_l

test_srom_d_l

J13

eb164.30

eb164.28

21164

eb164.2

SROM

eb164.4

test_srom_d

eb164.4 MK−2306−17

real_srom_d

MUX

3.10 dc Power Distribution

The EB164 derives its system power from a user-supplied PC power supply.

The power supply must provide +12 V dc and –12 V dc, –5 V dc, +3 V dc,

and Vdd (+5 V dc). The dc power is supplied through power connectors J18

and J29 (eb164.40). (See Figure 3–8.) Power is distributed to the board logic

through dedicated power planes within the 6-layer board structure.

As shown in Figure 3–8, the +12 V dc, –12 V dc, and –5 V dc are supplied to

ISA connectors J19, J20, and J21 (eb164.26). The +12 V dc and –12 V dc are

supplied to ISA connectors and PCI32 connectors J24 and J25 (eb164.22). The

+12 V dc is also supplied to the CPU fan connector J30 (eb164.40), auxiliary

fan connector pins on header J2 (eb164.37), and to the ﬂash ROM write-enable

conector J14 (eb164.33). Vdd is supplied to ISA connectors, PCI32 connectors

and most of the board’s integrated circuits. The +3 V dc is supplied to the

21164 microprocessor.

3–22 Functional Description