Golledge UM Crystal filter package options

GMCF-21 21G7B 21.4MHz 4 pole crystal filter with 7.5kHz 3dB bandwidth

  • 21.4MHz Centre Frequency
  • Four Pole
  • Two packages
  • Low insertion loss
Configurable Options
ParameterOption Code
Quantity / Special Request

Please specify the quantity you require below.

The GMCF-21 21G7B is supplied in either a leaded (UM-1 or UM-5 style) package, or a jacketed (UM-1J or UM-5J) package. UM-1 or UM-5 style packaged products are supplied in boxes or bags. Please see handling & storage specification for more information on how filter pairs are supplied for these products. UM-1J or UM-5J style packaged products are supplied on tape and reel. 300 pcs per reel is the standard T&R pack sizes for these products. Partial quantities may be supplied on tape (no reel), or in bulk. These filters are supplied as a pair of units with a pocket space between matching pairs, please see tape & reel specification for more information.
Product Description
The four pole 21G7B crystal filter with centre frequency of 21.4MHz, and minimum bandwidth of±7.5kHz 3dB @ 3dB, comes in two 7.8 x 3.2mm footprint leaded packages. This filter features low in-band ripple specifications of 1.0dB, and insertion loss of only 2.5dB, making it ideal for applications that require minimum design-in impact. Tight attenuation band less than ±14kHz @ -40dB and good guaranteed attenuation characteristics mean uncompromised receiver performance.
Centre frequency 21.4MHz
Dimensions Package options available - see Package Drawing
Operating temperature range -20 to +70°C
Number of poles 4
Pass band -3dB @ ±3.75kHz min
Attenuation band -40dB @ ±14.0kHz max
In-band ripple 1.0dB max
Insertion loss 2.5dB max
Guaranteed attenuation -65dB max +350 ~ +1000kHz
-80dB max -200 ~ -1000kHz
Termination 850Ω // 5.0pF (CC16pF)
Coupling capacitance (CC) 16pF
Package style UM-1/3Lx2, UM-5/3Lx2 (through-hole)
UM-1JN/3Lx2, UM-5JN/3Lx2 (SMT)
Package Drawing
Package footprint and configuration drawing for 2-unit UM-1 and UM-5 Crystal filters
Ordering Information

To request a quotation for the GMCF-21 21G7B please use the configurable options form to choose the options you require and then submit your configured product to our team. Our expert advisers are always happy to help with your requirements and can be contacted on +44 1460 256 100 or at sales@golledge.com.

Following product selection you will be issued with a seven character Golledge part number. Your Golledge part number is the internationally accepted Golledge manufacturing part number (MPN) that should be used for all project documentation, including bills of materials (BoMs) and purchase orders.

If you have any queries regarding any of our documentation our dedicated sales team will be happy to help.

Tape & Reel Specification
Tape and Reel specifications
UM-1J - A:330 B:24 C:14.1 D:8.4 E:12 F:4.6 G:80 H:21
UM-5J - A:180 B:24 C:12.5 D:8.4 E:12 F:4.4 G:60 H:21
Handling & Storage

ESD-HBM-1A Human Body Model (HBM) 1A (250V to <500V)

MSL1 Moisture Sensitivity Level (MSL): 1 (or not applicable)

4-pole filter packaging  

These filters are individually matched pairs. One filter is composed of two physical units, which have been factory-matched for optimum performance.

DO NOT MIX. Unmatched pairs will offer impaired performance.

For filters supplied in boxes, please refer to the above diagram.

Matched pairs may also be supplied in individual bags.

Resistance weld

PbFree Lead-free (< 0.1% by weight )

RoHS compliant with no exemptions RoHS compliant with no exemptions. See our declaration

REACH REACH compliant. See our statement

Conflict Minerals Statement Free of conflict minerals. See our declaration

Halogen Free Statement Free of Halogens. See our declaration

Ozone Depletion Statement Free of Ozone-depleting substances. See our declaration