W55RFS27T1B DataSheet

4

Revision: A3.0

Publish Date: Feb. 2010

- 4 -

Revision A1

1.2 W55RFS27T1B Pad Definition

1.2.1 Pad Description

Symbol

Pad

No.

I/O

Functional Description

S3

1

I

Manual-mode input, internally pull-high

S4

2

I

Manual-mode input , internally pull-high

CKSEL0

3

I

TEST

4

I

TEST=0 for 6-function mode, TEST=1 for 4-function mode

CKSEL1

5

I

ANT

6

O

RF signal output. An external matching circuit is necessary for connecting with

an antenna.

GND

7

Ground

Ground return path

VDD

8

Power

Power path

RESET

9

I

RESET=0 resets whole chip, internally pull-high

X1

10

I

Input of internal crystal oscillator to connect with an external crystal

X2

11

O

Output of internal crystal oscillator to connect with an external crystal

ID1

12

I

ID0

13

I

TXOUT

14

O

TXD Data output

S1/~TXD

15

I

Manual-mode input or uC-mode: ~TXD, internally pull-high

S2/~ENB

16

I

Manual-mode input or uC-mode: ~ENB, internally pull-high

1.2.2 Clock Frequency Select (CKSEL) Setup

(CKSEL1,CKSEL0)

Clock Frequency

(0,0)

27.145MHz

(0,1)

35.48 MHz

(1,0)

40.68 MHz

(1,1)

49.86 MHz