MICRF104

Micrel

MICRF104

2

November 8, 2001

Pin Description

Pin Number

Pin Name

Pin Function

1

VDDPWR

Positive power supply input for the DC/DC converter.

2, 4, 13

VSS

Ground return

3

5V

5V Output from the DC / DC converter

5

REFOSC

This is the timing reference frequency which is the transmit frequency

divided by 32. Connect a crystal (mode dependent) between this pin and

VSS, or drive the input with an AC coupled 0.5Vpp input clock. See

Refer-

ence Oscillator Section in this data sheet

6

RFSTBY

Input for transmitter standby control pin is pulled to VDDRF for transmit

operation and VSS for stand-by mode.

7

ANTM

Negative RF power output to drive the low side of the transmit loop antenna

8

ANTP

Positive RF power output to drive the high side of the transmit loop antenna

9

ASK

Amplitude Shift Key modulation data input pin.

10

VDDRF

Positive power supply input for the RF circuit. A power supply bypass

capacitor connected from VDDRF to VSS should have the shortest possible

path.

11

PC

Power Control Input. The voltage at this pin should be set between 0.3V to

0.4V for normal operation.

12

SW

DC/DC converter Switch. NPN output switch transistor collector.

14

EN

Chip Enable input. Active high

Pin Configuration

1

VDDPWR

VSS

5V

VSS

REFOSC

RFSTBY

ANTM

14 EN

VSS

SW

PC

VDDRF

ASK

ANTP

13

12

11

10

9

8

2

3

4

5

6

7

MICRF104BM