NXP Semiconductors SC16C652BIBS,157

Overview

SC16C652BIBS,157 from NXP Semiconductors (formerly Philips) is a dual-channel 32-byte FIFO UART IC for high-speed serial data communication in embedded industrial systems. It operates at 2.5 V/3.3 V/5 V, supports up to 5 Mbit/s (at 5 V/3.3 V), integrates IrDA 1.0 encoder/decoder, and delivers independent programmable baud rate generation for TX/RX channels - used in industrial gateways requiring reliable RS-232/485 modem interface with hardware flow control.

For engineers reviewing the SC16C652BIBS,157 datasheet, SC16C652BIBS,157 pinout, SC16C652BIBS,157 application, or SC16C652BIBS,157 equivalent, key selection criteria include dual-channel FIFO depth (32-byte TX/RX), HVQFN32 package compatibility, IrDA 1.0 support at 115.2 kbit/s, industrial temperature range (−40 °C to +85 °C), and software compatibility with legacy 16C450/16C550 UARTs.

Technical Context

The SC16C652BIBS,157 implements two independent UART channels (A/B) with fully separate register sets, FIFO control, and interrupt logic - each supporting 5–8-bit word length, 1/1.5/2 stop bits, even/odd/no parity, and false start-bit detection. Its internal baud rate generator divides a 16× clock (up to 80 MHz) by programmable divisors (1–65535) via DLL/DLM registers to achieve DC–5 Mbit/s rates.

Hardware flow control uses RTS/CTS pins per channel with Auto-RTS activation triggered by FIFO level thresholds; software flow control supports Xon/Xoff with single/dual-character matching. Internal loop-back mode isolates link faults without external wiring, and DMA mode toggles TXRDY/RXRDY signals based on FIFO trigger levels rather than simple empty/full states.

Key Specifications

Pinout & Package

SC16C652BIBS,157 is housed in a 5 × 5 × 0.85 mm HVQFN32 package (SOT617-1) with 32 terminals, thermal pad exposed on underside for enhanced heat dissipation in compact industrial modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual UART applications.

Compared with SC16C652BIBS,157, the SC16C652BIB48,157 offers identical functionality in a larger LQFP48 package for improved thermal handling, while the TL16C752BPFB provides GPIO flexibility at the cost of IrDA support and pin compatibility - making SC16C652BIBS,157 optimal for space-constrained, infrared-capable industrial designs.

Availability

SC16C652BIBS,157 is available at Aetrix Electronics and suitable for industrial serial gateways, embedded modem interfaces, IrDA wireless terminals, and ruggedized vehicle telematics requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SC16C652BIBS,157 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT markets, with roots in Philips' semiconductor division.

The SC16C652BIBS,157 belongs to NXP's legacy UART product line designed specifically for robust, low-power, multi-protocol serial communication in harsh industrial environments - emphasizing interoperability with legacy 16C550 systems while adding FIFO depth, IrDA, and voltage flexibility.

FAQ

What voltage levels does the SC16C652BIBS,157 support, and are its inputs 5 V tolerant?

The SC16C652BIBS,157 operates from 2.5 V, 3.3 V, or 5 V supply rails and features 5 V-tolerant inputs - allowing direct interfacing with legacy 5 V logic without level shifters. This tolerance applies to all control and data pins (D0–D7, CSA, CSB, IOR, IOW, RESET, A0–A2, etc.), simplifying mixed-voltage system integration while maintaining full 5 Mbit/s capability at 5 V and 3.3 V.

Does the SC16C652BIBS,157 support independent baud rates for transmit and receive on each channel?

Yes, the SC16C652BIBS,157 provides independent programmable baud rate generators for both transmit and receive paths per channel (A and B). This is achieved through separate access to the DLL/DLM divisor registers using address bits A0–A2 and the Line Control Register (LCR) bit 7, enabling asymmetric full-duplex operation - for example, SC16C652BIBS,157 can run UART A at 921.6 kbit/s TX / 115.2 kbit/s RX while UART B runs at different rates simultaneously.

How does the SC16C652BIBS,157 implement hardware flow control, and what pins are involved?

The SC16C652BIBS,157 implements per-channel hardware flow control using RTS (output) and CTS (input) pins: RTSA/RTSB assert low when their respective RX FIFO reaches the programmed trigger level, and CTSA/CTSB being low pauses TX transmission after the current character's stop bit. This behavior is enabled via Enhanced Feature Register (EFR) bits 6 (RTS) and 7 (CTS), and status is reported in the Modem Status Register (MSR) - ensuring zero-data-loss operation in high-speed modem links.

What is the function of the RXRDY and TXRDY pins on the SC16C652BIBS,157, and how do they behave in DMA mode?

On the SC16C652BIBS,157, RXRDYA/B and TXRDYA/B are active-low status outputs indicating FIFO readiness: RXRDY asserts low when ≥1 byte is available in the RX FIFO; TXRDY asserts low when ≥1 location is empty in the TX FIFO. In DMA mode (FCR[3]=1), their transitions change - RXRDY toggles low when FIFO reaches trigger level or times out; TXRDY toggles low when FIFO drops below trigger level - enabling precise DMA buffer synchronization without CPU polling.

Can the SC16C652BIBS,157 be used with an external clock source, and what is the maximum supported frequency?

Yes, the SC16C652BIBS,157 accepts an external clock up to 80 MHz applied to the XTAL1 pin, bypassing the internal crystal oscillator. This clock directly drives the programmable baud rate generator, enabling custom data rates beyond standard tables - for instance, a 75 MHz input yields a 4.6875 Mbit/s rate with divisor 16. XTAL2 must be left open in external clock mode, and full-rail swing is recommended for reliable operation at maximum frequency.