Document Number: MC34673 Freescale Semiconductor Rev. 1.0, 01/2008 Advance Information High Input Voltage 1.2A Charger 34673 for Single-cell Li-Ion Batteries The MC34673 is a cost-effective fully-integrated battery charger for Li-Ion or Li-Polymer batteries. The high input voltage, up to 28V, POWER MANAGEMENT IC eliminates the input over-voltage protection circuit required in handheld devices such as PDAs, cell phones, portable video game players and digital still cameras. A typical charge cycle includes trickle, constant-current (CC) and constant-voltage (CV) charge modes. The CC-mode current is programmable up to 1.2A with an external resistor. The voltage across the external resistor is also used to monitor the actual charge current. The constant voltage is fixed at 4.2V with 0.7% accuracy over a -20C to 70C temperature range. The trickle-mode current is preset to 20% EP SUFFIX (PB-FREE) of the CC-mode current when the battery voltage is lower than the 98ASA10774D trickle-mode threshold. The end-of-charge (EOC) current threshold is 8-PIN UDFN preset to 10% of the CC-mode current to save the board space and cost. A charge current thermal foldback feature limits the charge current when the IC internal temperature rises to a preset threshold. ORDERING INFORMATION The MC34673 also protects the system with its input over-voltage Temperature protection (OVP) feature. In addition, the MC34673 has a 2.6V falling Device Package Range (T ) power-on-reset (POR) threshold, making it perfect to work with current A limited power supplies. Three indication pins (PPR, CHG and FAST) MC34673AEP/R2 -40C to 85C 8-UDFN can be simply interfaced to a microprocessor or LEDs. When no power supply is connected, or when disabled, the charger draws less than 1.0A leakage current from the battery. Features No external MOSFET, reverse-blocking diode or current-sense resistor are required Guaranteed maximum 1.2A programmable CC-mode current 0.7% voltage accuracy over -20C to 70C 6% current accuracy over -40C to 85C 28V maximum voltage for the power input with 6.8V over-voltage protection threshold 2.6V minimum input operating voltage Trickle charge for fully discharged batteries Charge current monitor Charge current thermal foldback Pb-free packaging designated by suffix code EP 34673 V IN VIN BAT TO BATTERY C IN GND C OUT ISET R CHG ISET V IO PPR OFF ON EN FAST TO MCU Figure 1. 34673 Simplified Application Diagram * This document contains certain information on a new product. Specifications and information herein are subject to change without notice. Freescale Semiconductor, Inc., 2007-8. All rights reserved.INTERNAL BLOCK DIAGRAM INTERNAL BLOCK DIAGRAM VIN BAT V Internal IN + Supply Monitor V REF Charge Control REF ISET PPR + V OS I REF VIN + + Die Temp BAT + 110C CHG + Logic I EN Control EOC FAST GND Figure 2. 34673 Simplified Internal Block Diagram 34673 Analog Integrated Circuit Device Data 2 Freescale Semiconductor