LT1511CSW

• Product Introduction

LT1511CSW 

peculiarity

• Simple design charging nickel-cadmium batteries, nickel-metal hydride batteries and lithium rechargeable batteries The charging current is programmed by a resistor or DAC
• The adapter current loop allows the maximum possible charging current while using the computer
• Precision voltage charging mode with 0.5% accuracy
• Current mode PWM for high-efficiency 4A internal switching
• 5% charge current accuracy
• Adjustable undervoltage lockout
• Automatically shuts down when the AC adapter is removed
• Low reverse battery leakage current: 3μA
• Current sensing is available at the terminals of both batteries
• Soft start of the charging current
• Shutdown control

description

® The LT 1511 current-mode PWM battery charger is the simplest and most efficient solution for modern fast-charging rechargeable batteries, including lithium-ion batteries (Li-ion), nickel metal hydride (NiMH), and nickel-cadmium (NiCd), which require constant current and/or constant voltage charging. An internal switch capable of providing 3A DC current (4A peak current). The full charging current can be within 5% through the resistor or DAC. With a 0.5% voltage reference, the LT1511 meets the charging requirements of critical constant voltage lithium-ion batteries. The third control loop provides the specification of the current drawn from the AC adapter. This allows the device to be operated simultaneously and the battery to charge without overloading the adapter. The charging current is reduced to keep the adapter at the current specified level. The LT1511 can be charged from a battery ranging from 1V to 20V. Current grounding detection is not necessary, it can be directly connected to the negative electrode of the battery to ground. Saturation switches running at 200kHz make charging efficiency high and inductor size small. There is no need to block between the diode chip and the battery because the chip goes into sleep mode when the wall adapter pulls out the drain at only 3μA.