The DataSheet of CH315 (the first)

3

5. Function

CH315 can direct use USB power. When using 5V power, V3 pin must connect with about 0.01uF

decoupling capacitance. When using 3.3V power, V3 must connect with VCC, and input the outside 3.3V

power.

CH315G using category 5 or category 5 unshielded twisted-pair super (net wire) or USB signal wire

and similar difference signal twisted-pair. If the characteristic impedance is not matching, need to parallel

connect resistor to ground of output port XD+/XD-.

The transfer distance of CH315G is relative with transfer wire quality. When using common net wire,

the transfer distance is no less than 300m of low-speed USB signal, the transfer distance is no less than 75m

of full-speed USB signal. The current resistor of common net wire is less than 10Ω/100m. If the current

resistor is too big, it will influence on transfer distance, and influence on USB supply power, upgrade ground

power of device port.

The transfer distance of CH315G has relative with USB host time characteristics of computer chip

groups. For full-speed USB signal, the trip acknowledge time of electron in transfer wire does not pass

computer waiting time (several ns), so the transfer distance is limited.

The ACT# is USB transfer current status output of CH315H, connect with LED to indicate USB

12

2

UD-

USB signal

Directly connect to USB bus D- data bus

1

No

REF

Consult

power

Consult power of internal simulate circuit, require an

resistor and decoupling capacitance

5

No

XD+

Simulate

signal

Directly connect to difference extension wire positive port

4

No

XD-

Simulate

signal

Directly connect to difference extension wire negative

port

No

14

OPIP

IN

Separate transfer P signal input, connect with photic

coupler or magnetism coupler P logic output port

No

15

OPIN

IN

Separate transfer N signal input, connect with photic

coupler or magnetism coupler N logic output port

No

6

OPOP

OUT

Separate transfer P signal output, connect with photic

coupler or magnetism coupler P control input port

No

7

OPON

OUT

Separate transfer N signal output, connect with photic

coupler or magnetism coupler N control input port

No

5

LSO#

OUT

USB transfer speed automatically check the result ouput.

Low-level is USB low-speed 1.5Mbps, high-level is USB

full-speed 12Mbps

No

4

LSI#

IN

USB transfer speed select input,

Low-level is USB-low speed 1.5Mbps, high-level is USB

full-speed 12Mbps.

10

12

UP#

IN

Mode select input, with pull-up resistor,

Low-level is upstream mode, high-level is downstream

mode

No

11

ACT#

Drain open

OUT

USB transfer status output, active with low-level, with

pull-up resistor

7,8,9

9,10

NC.

Un-connect

Forbid to connect