参数资料
型号: LTC1983ES6-3#TR
厂商: Linear Technology
文件页数: 6/12页
文件大小: 0K
描述: IC REG SWITCHD CAP INV -3V SOT23
标准包装: 2,500
类型: 切换式电容器(充电泵),反相
输出类型: 固定
输出数: 1
输出电压: -3V
输入电压: 2.3 V ~ 5.5 V
PWM 型: Burst Mode?
频率 - 开关: 900kHz
电流 - 输出: 100mA
同步整流器:
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: SOT-23-6 细型,TSOT-23-6
包装: 带卷 (TR)
供应商设备封装: TSOT-23-6
其它名称: LTC1983ES6-3TR
LTC1983ES63TR
LTC1983-3/LTC1983-5
OPERATIO
(Refer to Block Diagram)
The LTC1983-3/LTC1983-5 use a switched capacitor
charge pump to invert a positive input voltage to a regu-
lated –3V ± 4% (LTC1983-3) or –5 ± 4% (LTC1983-5)
output voltage. Regulation is achieved by sensing the
output voltage through an internal resistor divider and
enabling the charge pump when the output voltage droops
above the upper trip point of COMP1. When the charge
pump is enabled, a 2-phase, nonoverlapping clock con-
trols the charge pump switches. Clock 1 closes the S1
switches which enables the flying capacitor to charge up
to the V IN voltage. Clock 2 closes the S2 switches that
invert the V IN voltage and connect the bottom plate of C FLY
to the output capacitor at V OUT . This sequence of charging
and discharging continues at a free-running frequency of
900kHz (typ) until the output voltage has been pumped
down to the lower trip point of COMP1 and the charge
pump is disabled. When the charge pump is disabled, the
LTC1983 draws only 25 μ A (typ) from V IN which provides
high efficiency at low load conditions.
In shutdown mode, all circuitry is turned off and the part
draws less than 1 μ A from the V IN supply. V OUT is also
disconnected from V IN and C FLY . The SHDN pin has a
threshold of approximately 0.7V. The part enters shut-
down when a low is applied to the SHDN pin. The SHDN pin
should not be floated; it must be driven with a logic high
or low.
Open-Loop Operation
The LTC1983-3/LTC1983-5 inverting charge pumps regu-
late at –3V/–5V respectively, unless the input voltage is too
low or the output current is too high. The equations for
output voltage regulation are as follows:
V IN –5.06V > I OUT ? R OUT (LTC1983-5)
V IN –3.06V > I OUT ? R OUT (LTC1983-3)
If this condition is not met, then the part will run in open
loop mode and act as a low output impedance inverter for
which the output voltage will be:
V OUT = –[V IN –(I OUT ? R OUT )]
For all R OUT values, check the corresponding curves in
the Typical Performance Characteristics section (Note:
C FLY = 1 μ F for all R OUT curves). The R OUT value will be
different for different flying caps, as shown in the follow-
ing equation:
Short-Circuit/Thermal Protection
During short-circuit conditions, the LTC1983 will draw
several hundred milliamps from V IN causing a rise in the
junction temperature. On-chip thermal shutdown cir-
cuitry disables the charge pump once the junction tem-
perature exceeds ≈ 155 ° C, and reenables the charge pump
once the junction temperature falls back to ≈ 145 ° C. The
LTC1983 will cycle in and out of thermal shutdown
indefinitely without latchup or damage until the V OUT
short is removed.
Capacitor Selection
For best performance, it is recommended that low ESR
capacitors be used for both C IN and C OUT to reduce noise
and ripple. The C IN and C OUT capacitors should be either
ceramic or tantalum and should be 4.7 μ F or greater.
Aluminum electrolytic are not recommended because of
their high equivalent series resistance (ESR). If the source
impedance is very low, C IN may not be needed. Increasing
the size of C OUT to 10 μ F or greater will reduce output
voltage ripple. The flying capacitor and C OUT should also
have low equivalent series inductance (ESL). The board
layout is critical as well for inductance for the same reason
(the suggested board layout should be used).
A ceramic capacitor is recommended for the flying capaci-
tor with a value in the range of 0.1 μ F to 4.7 μ F. Note that
a large value flying cap (>1 μ F) will increase output ripple
unless C OUT is also increased. For very low load applica-
tions, C1 may be reduced to 0.01 μ F to 0.047 μ F. This will
reduce output ripple at the expense of efficiency and
maximum output current.
1983fa
6
相关PDF资料
PDF描述
MAX6865UK45D6L+T IC MPU SUPERVISOR SOT23-5
MAX6865UK45D5S+T IC MPU SUPERVISOR SOT23-5
VI-J7M-CZ-F3 CONVERTER MOD DC/DC 10V 25W
CGS224U016X4C CAP ALUM 220000UF 16V SCREW
MAX6865UK45D5L+T IC MPU SUPERVISOR SOT23-5
相关代理商/技术参数
参数描述
LTC1983ES6-5#PBF 制造商:Linear Technology 功能描述:IC INVERTING CHARGE PUMP CONV 6-SOT-23 制造商:Linear Technology 功能描述:IC, INVERTING CHARGE PUMP CONV, 6-SOT-23 制造商:Linear Technology 功能描述:IC, INVERTING CHARGE PUMP CONV, 6-SOT-23; Primary Input Voltage:5V; No. of Outputs:1; Output Voltage:-5V; Output Current:100mA; No. of Pins:6; Operating Temperature Min:-40C; Operating Temperature Max:85C; MSL:MSL 1 - Unlimited ;RoHS Compliant: Yes
LTC1983ES6-5#TR 功能描述:IC REG SWITCHD CAP INV -5V SOT23 RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:500 系列:- 类型:切换式电容器(充电泵),反相 输出类型:固定 输出数:1 输出电压:-3V 输入电压:2.3 V ~ 5.5 V PWM 型:Burst Mode? 频率 - 开关:900kHz 电流 - 输出:100mA 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SOT-23-6 细型,TSOT-23-6 包装:带卷 (TR) 供应商设备封装:TSOT-23-6 其它名称:LTC1983ES6-3#TRMTR
LTC1983ES6-5#TRM 功能描述:IC REG SWITCHD CAP INV -5V SOT23 RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:2,500 系列:- 类型:升压(升压) 输出类型:可调式 输出数:1 输出电压:1.24 V ~ 30 V 输入电压:1.5 V ~ 12 V PWM 型:电流模式,混合 频率 - 开关:600kHz 电流 - 输出:500mA 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-SOIC(0.154",3.90mm 宽) 包装:带卷 (TR) 供应商设备封装:8-SOIC
LTC1983ES6-5#TRMPBF 功能描述:IC REG SWITCHD CAP INV -5V SOT23 RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 产品培训模块:High Efficiency Current Mode Switching Regulators CMOS LDO Regulators 特色产品:BD91x Series Step-Down Regulators 标准包装:2,500 系列:- 类型:降压(降压) 输出类型:两者兼有 输出数:2 输出电压:3.3V,0.8 V ~ 2.5 V 输入电压:4.5 V ~ 5.5 V PWM 型:电流模式 频率 - 开关:1MHz 电流 - 输出:1.5A 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:20-VFQFN 裸露焊盘 包装:带卷 (TR) 供应商设备封装:VQFN020V4040 产品目录页面:1373 (CN2011-ZH PDF) 其它名称:BD9152MUV-E2TR
LTC1983ES6-5#TRPBF 功能描述:IC REG SWITCHD CAP INV -5V SOT23 RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:500 系列:- 类型:切换式电容器(充电泵),反相 输出类型:固定 输出数:1 输出电压:-3V 输入电压:2.3 V ~ 5.5 V PWM 型:Burst Mode? 频率 - 开关:900kHz 电流 - 输出:100mA 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SOT-23-6 细型,TSOT-23-6 包装:带卷 (TR) 供应商设备封装:TSOT-23-6 其它名称:LTC1983ES6-3#TRMTR