Document Number: 38-08008 Rev. *H Page 22 of 39
USB Host Controller Pins Description
The SL811HST-AXC is packaged in a 48-pin TQFP. These devices require a 3.3 VDC power source and an external 12 or 48 MHz
crystal or clock..
Table 34. Pin and Signal Description for Pins
48-Pin TQFP
AXC Pin No.
Pin Type Pin Name Pin Description
1 NC NC No connection.
2 NC NC No connection.
3INnWRWrite Strobe Input. An active LOW input used with nCS to write to
registers/data memory.
4INnCSActive LOW 48-Pin TQFP Chip select. Used with nRD and nWr when
accessing the 48-Pin TQFP.
5
[11]
IN CM Clock Multiply. Select 12 MHz/48 MHz Clock Source.
6 VDD1 +3.3 VDC Power for USB Transceivers. V
DD1
may be connected to V
DD
.
7 BIDIR DATA + USB Differential Data Signal HIGH Side.
8 BIDIR DATA - USB Differential Data Signal LOW Side.
9 GND USB GND Ground Connection for USB.
10 NC NC No connection.
11 NC NC No connection.
12 NC NC No connection.
13 NC NC No connection.
14 NC NC No connection.
15
[12]
VDD +3.3 VDC Device V
DD
Power.
16 IN CLK/X1 Clock or External Crystal X1 connection. The X1/X2 Clock requires external
12 or 48 MHz matching crystal or clock source.
17 OUT X2 External Crystal X2 connection.
18 IN nRST Device active low reset input.
19 OUT INTRQ Active HIGH Interrupt Request output to external controller.
20 GND GND Device Ground.
21 BIDIR D0 Data 0. Microprocessor Data/Address Bus.
22 NC NC No connection.
23 NC NC No connection.
24 NC NC No connection.
25 NC NC No connection.
26 NC NC No connection.
27 BIDIR D1 Data 1. Microprocessor Data/Address Bus.
28 BIDIR D2 Data 2. Microprocessor Data/Address Bus.
29 BIDIR D3 Data 3. Microprocessor Data/Address Bus.
30 GND GND Device Ground.
31 BIDIR D4 Data 4. Microprocessor Data/Address Bus.
32 BIDIR D5 Data 5. Microprocessor Data/Address Bus.
Notes
11. The CM Clock Multiplier pin must be tied HIGH for a 12 MHz clock source and tied to ground for a 48 MHz clock source.
12. VDD can be derived from the USB supply. See Figure 5 on page 21.
