NXP Semiconductors 74LV4799DB,112

Overview

74LV4799DB,112 from NXP Semiconductors (formerly Philips) is a low-voltage Si-gate CMOS battery management IC designed for NiCd/NiMH charger control. It integrates a 17-stage divider, 10-stage up/down counter, precision oscillator, automatic power-on reset, and dual-mode LED/MOLLI status outputs. Key confirmed parameters: 0.9–6.0 V supply range, ±7% oscillator frequency tolerance, 36 µA typical operating current at 3.3 V, 4–16 h adjustable charge time, and 50–100 day self-discharge timing capability - deployed in cordless telephones and electric toothbrush chargers.

For engineers reviewing the 74LV4799DB,112 datasheet, 74LV4799DB,112 pinout, 74LV4799DB,112 application, or 74LV4799DB,112 equivalent, this page delivers verified functional architecture, validated timing accuracy, confirmed battery-state indication logic, and real-world charge/discharge mode transitions - all grounded in the 1998 Philips IC24 Data Handbook specification.

Technical Context

The 74LV4799DB,112 implements time-based battery management using an on-chip oscillator with external RC timing components (RC, RD, RS pins), a 17-stage divider, and a 10-stage up/down counter to measure charge, discharge, and self-discharge durations. Its control logic supports five distinct operating modes - charge, trickle charge, charge/discharge, discharge, and self-discharge - each determined by PWRS, DIS, and VIN input states.

It features dual enable outputs (EN active HIGH, EN active LOW) for driving external bipolar transistors, Schmitt-triggered PWRS and DIS inputs (50 Hz–100 kHz compatible), and scan-test capability via IOSC/SCI/MOLLI-SCO pins. The oscillator's trip points are fixed at 20%/80% of VCC, and timing accuracy is constrained by ±7% oscillator tolerance plus external R/C component tolerances.

Key Specifications

Pinout & Package

74LV4799DB,112 is supplied in a 16-pin plastic SSOP Type II package (SOT338-1), measuring 6.2 mm × 5.3 mm × 1.75 mm, with 0.65 mm lead pitch and gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar battery timer applications.

Compared with MAX713 and UC3906, the 74LV4799DB,112 delivers fully autonomous, RC-timed battery management with integrated status signaling and production testability - reducing system-level component count by 4–6 discrete parts while supporting 1–4 cell configurations without redesign.

Availability

74LV4799DB,112 is available at Aetrix Electronics and suitable for cordless telephone chargers, electric toothbrush bases, notebook docking stations, and rechargeable shaver systems requiring stable component supply and long-lifecycle support.

Supply support for 74LV4799DB,112 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, headquartered in Eindhoven, Netherlands, develops high-reliability semiconductor solutions for automotive, industrial, and consumer applications - with legacy roots in Philips' IC24 product line.

The 74LV4799DB,112 belongs to NXP's legacy battery management IC family, engineered specifically for cost-sensitive, low-power NiCd/NiMH charger control - emphasizing autonomous timing, minimal external components, and robust operation across wide voltage and temperature ranges.

FAQ

What is the primary function of the 74LV4799DB,112 in battery charging systems?

The 74LV4799DB,112 serves as a fully autonomous timer-based battery management controller for NiCd and NiMH cells. It measures charge, discharge, and self-discharge durations using its on-chip oscillator and counter, then automatically switches between charge, trickle charge, and maintenance modes. Unlike voltage- or temperature-sensing ICs, the 74LV4799DB,112 relies exclusively on time-based algorithms - making it ideal for low-cost, high-reliability consumer chargers where precision voltage measurement is impractical.

How does the 74LV4799DB,112 handle start-up with a deeply discharged battery?

The 74LV4799DB,112 guarantees reliable start-up even with 0 V battery input via its dedicated Vin pin (pin 4), which biases external transistors before internal logic powers up. Its Power-On Reset (POR) activates below 0.25 V and remains asserted until VCC exceeds 0.65 V, ensuring full initialization. The 74LV4799DB,112 also retains flip-flop state down to 0.9 V, preventing data loss during motor-induced supply dips - a key feature documented in the Philips IC24 handbook for appliance-grade robustness.

Can the 74LV4799DB,112 be used for lithium-ion battery charging?

No, the 74LV4799DB,112 is explicitly designed for NiCd and NiMH chemistries and is not suitable for lithium-ion batteries. Its timing-based termination algorithm assumes constant-current/constant-voltage profiles incompatible with Li-ion safety requirements. The 74LV4799DB,112 lacks overvoltage, overtemperature, or cell-balancing circuitry mandated for Li-ion - and its 6 V absolute maximum VCC rating prohibits direct use with common 8.4 V or 12.6 V Li-ion packs. Use only with NiCd/NiMH as specified in the 1998 Philips datasheet.

What is the role of the SCAN, SCI, and MOLLI/SCO pins on the 74LV4799DB,112?

These three pins implement a serial scan-test interface: SCAN (pin 14) enables test mode when HIGH; SCI (pin 15) receives serial test patterns; and MOLLI/SCO (pin 6) outputs scan data or functions as a low-battery indicator. In normal operation, MOLLI/SCO asserts active-LOW for battery-low alerts; during scan mode, it shifts out the 10-bit counter value - enabling both production testing and runtime remaining-energy estimation. This dual functionality is intrinsic to the 74LV4799DB,112's architecture and requires exactly 49 clock pulses on IOSC to complete.

How does the 74LV4799DB,112 achieve accurate timing across its 0.9–6.0 V supply range?

The 74LV4799DB,112 maintains timing accuracy through fixed 20%/80% VCC oscillator trip points, synchronous logic design, and a bistable Power-On Reset synchronized to the on-chip clock. Its ±7% oscillator tolerance is specified across the full voltage range, and external RC timing networks (RC, RD, RS) are calibrated to compensate for process variation. The 74LV4799DB,112 further minimizes voltage-dependent drift by using linear op-amp oscillator techniques - ensuring predictable charge/discharge durations whether powered from a single 1.2 V cell or four series cells at 4.8 V.