描述 Description

The MCP1256, MCP1257, MCP1258 and MCP1259 are inductorless, positive regulated charge pump DC/DC converters. Generating a regulated 3.3 V output voltage from a 1.8 V to 3.6 V input, they are specifically designed for applications operating from 2 cell alkaline, 2 cell Ni-Cd, 2 cell Ni-MH, or one primary lithium coin cell battery. These devices automatically switch from 1.5x to 2x boost operation modes to maintain high efficiency. In addition, at light output loads, the MCP1256 and MCP1257 can be placed in a sleep mode, lowering the quiescent current while maintaining the regulated output voltage. Alternatively, the MCP1258 and MCP1259 provide a bypass feature connecting the input voltage to the output. This allows for real-time clocks, microcontrollers or other system devices to remain biased with virtually no current being consumed by the MCP1258 or MPC1259. In normal operation, the charge pumps switch at a fixed 650 kHz, avoiding sensitive IF bands, and the output voltage ripple is below 20 mVP-P at load currents up to 100 mA. The MCP1256 and MCP1258 feature a power-good output that can be used to detect out-of-regulation conditions. The MCP1257 and MCP1259 feature a low battery indication that issues a warning if the input voltage drops below a preset voltage threshold. Extremely low supply current and few external parts (4 capacitors) make these devices ideal for small, battery powered applications. A shutdown mode is also provided for further power reduction. The devices incorporate thermal and short-circuit protection.

特性 Features

High accuracy 3.3 V ±3.0 % output voltage
Accepts 1.8 V to 3.6 V input voltages
Supplies up to 100 mA output current
Low 20 mVp-p output voltage ripple
Integrated thermal shutdown and short circuit protection
Uses small ceramic capacitors
Operates at 650 kHz switching frequency
Low-power sleep mode feature on MCP1256/7
Bypass mode on MCP1258/9
Low-power 0.1 μA shutdown mode
Shutdown input compatible with 1.8 V logic
Soft-start circuitry to minimize inrush current
Available in 10 pin 3x3 DFN or 10 pin MSOP packages

簡介

MCP1257屬于集成電路（IC）的穩(wěn)壓器-DC-DC開關穩(wěn)壓器。由制造生產的MCP1257穩(wěn)壓器 - DC-DC 開關穩(wěn)壓器DC-DC 開關穩(wěn)壓器 PMIC（電源管理集成電路）產品族中的產品是元器件級設備，用于需要穩(wěn)定 DC 輸入電壓和/或將其轉換為不同幅度的輸出電壓的應用。這些器件與稱為“控制器”PMIC 的類似產品的區(qū)別在于集成了主開關元件，設備提供的電力會通過該元件。