Micrel, Inc.

MICRF229

April 15, 2015

2

Revision 1.0

Ordering Information

Part Number

Top Marking

Junction

Temperature

Range

Package

MICRF229YQS

MICRF229YQS

–40°C to +105°C

16-Pin 4.9mm × 6.0mm QSOP

Pin Configuration

16-Pin 4.9mm × 6.0mm QSOP (QS)

(Top View)

Pin Description

Pin

Number

Pin

Name

Type

Pin Function

1

RO1

In

Reference Resonator Connection (to the Pierce oscillator): Can also be driven by external

GND during normal operation.

2

RFGND

Supply

Ground Connection for ANT RF Input: Connect to PCB ground plane.

3

ANT

Input

Antenna Input: RF signal input from antenna. Internally AC coupled. It is recommended to use

a matching network with an inductor to RF ground to improve ESD protection.

4

RFGND

Supply

Ground Connection for ANT RF Input: Connect to PCB ground plane.

5

CDEC

Supply

Internal Supply Decoupling Access: Bypass to PCB ground plane with a 0.1µF ceramic

capacitor located as close to pin as possible. Maximum operating voltage is 3.6V.

6

SQ

Input

Squelch Control Logic-Level Input: An internal pull-

up (3μA typical) pulls the logic-input HIGH

when the device is enabled. This feature is not recommended in MICRF229 and this pin

should remain floating.

7

VDD

Supply

Positive Supply Connection (for all chip functions): Bypass with 1µF capacitor located as close

to the VDD pin as possible.