Freescale Semiconductor MC145572PBR2

The MC145572 implements Layer 1 functions at an ISDN Basic Access U reference point. It can be configured for line-termination or network-termination use and operates with 2B1Q signaling. The circuit supports two 64 kbit/s B channels and one 16 kbit/s D channel in each direction; framing and maintenance produce a 160 kbit/s data stream at an 80 kbaud line signaling rate.

The manufacturer manual contains a 44-lead PB TQFP pin assignment and mechanical outline. The LCDChip registry calls this 44-LQFP and maps it to 44-LQFP.jpg. Verify the exact PB outline, lead pitch, pin-one position and board land pattern; the generic registry label is not a mechanical drawing. PBR2 packing details need exact-code supplier confirmation.

Layout checks

• Compare the PCB land pattern with the manufacturer's PB TQFP mechanical outline.
• Observe line-transformer and analog layout guidance for the 2B1Q interface.
• Place supply bypassing and clock components close to the relevant pins.

The registered package JPG is missing locally; this draft must not be published until the image and package mapping are checked.

Section 3 and the MC145572PB pin-assignment figure in the manufacturer manual identify the principal pin groups. Check its complete top-view drawing for pin numbers and mode-dependent multiplexing.

Do not transfer pin numbers from the 44-lead PLCC option or from MC145572A variants without checking the PB diagram.

The values describe the MC145572 base device and relevant PB package. Apply the manufacturer's detailed electrical tables and device errata to the exact production revision.

Any candidate must be compared for 2B1Q analog performance, LT/NT operation, GCI or IDL timing, serial/parallel control registers, maintenance-channel behavior, supply and transformer network, temperature range and PB TQFP pinout. The related MC145472/MC14LC5472 family is not a verified drop-in substitute: Motorola notes that some loopback software may require changes.

No internal alternative-product link is shown because a compatible exact ordering code with verified LCDChip URL was not established.

Motorola authored the MC145572 U-Interface Transceiver manual, now hosted by NXP. NXP lists the base MC145572 as no longer manufactured and provides device errata. Match the mask revision and the complete PBR2 supply-chain code to the applicable manual and errata before purchase.

Verify manufacturer and lot markings, original PB package, mask revision, storage and ESD handling. Public listings for this discontinued part conflict on stock and often require RFQ; the catalog's inventory and price are not a confirmed current distributor offer.

Before a repair or redesign, verify PB pin assignment, transformer specifications, surge protection, line impedance, control-port selection, clock/reset timing and revision-specific errata. The missing JPG, unresolved complete PBR2 suffix and unverified exact-code price and inventory prevent publication.