CDPCLK4 datasheet(130/274 Pages) ALTERA

130 / 274 page

7–8

Chapter 7: High-Speed Differential Interfaces in the Cyclone III Device Family

High-Speed I/O Standards Support

Cyclone III Device Handbook

December 2011

Altera Corporation

Volume 1

Designing with LVDS

Cyclone III device family I/O banks support LVDS I/O standard. The left and right

I/O banks support true LVDS transmitters. On the top and bottom I/O banks, the

emulated LVDS transmitters are supported using two single-ended output buffers

with external resistors. One of the single-ended output buffers is programmed to have

opposite polarity. The LVDS receiver requires an external 100- termination resistor

between the two signals at the input buffer.

Figure 7–2 shows a point-to-point LVDS interface using Cyclone III device family true

LVDS output and input buffers.

Figure 7–3 shows a point-to-point LVDS interface with Cyclone III device family

LVDS using two single-ended output buffers and external resistors.

BLVDS I/O Standard Support in the Cyclone III Device Family

The BLVDS I/O standard is a high-speed differential data transmission technology

that extends the benefits of standard point-to-point LVDS to multipoint configuration

that supports bidirectional half-duplex communication. BLVDS differs from standard

LVDS by providing a higher drive to achieve similar signal swings at the receiver

while loaded with two terminations at both ends of the bus.

Figure 7–2. Cyclone III Device Family LVDS Interface with True Output Buffer on the Left and Right I/O Banks

Transmitting Device

Cyclone III Device Family

100

Cyclone III

Device

Family Logic

Array

100

Input Buffer

Output Buffer

Receiving Device

txout +

txout -

rxin +

rxin -

txout +

txout -

rxin +

rxin -

Figure 7–3. LVDS Interface with External Resistor Network on the Top and Bottom I/O Banks (1)

Note to Figure 7–3:

(1) R

S = 120  ; RP =170 

LVDS Receiver

100

Cyclone III Device Family

Resistor Network

Emulated

LVDS Transmitter

CDPCLK4 Scheda tecnica(PDF) 130 Page - Altera Corporation

CDPCLK4 Scheda tecnica(HTML) 130 Page - Altera Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Scheda tecnica Scarica

Link URL