- 您现在的位置：买卖IC网 > PDF目录3472 > LT1621CGN#PBF (Linear Technology)IC AMP R-R CURRENT SENSE 16-SSOP PDF资料下载
参数资料
| 型号： | LT1621CGN#PBF |
| 厂商： | Linear Technology |
| 文件页数： | 11/12页 |
| 文件大小： | 0K |
| 描述： | IC AMP R-R CURRENT SENSE 16-SSOP |
| 标准包装： | 100 |
| 放大器类型： | 电流检测 |
| 电路数： | 2 |
| 输出类型： | 满摆幅 |
| 电流 - 输入偏压： | 20nA |
| 电压 - 输入偏移： | 6000µV |
| 电流 - 电源： | 2.3mA |
| 电压 - 电源，单路/双路(±)： | 4.5 V ~ 5.5 V |
| 工作温度： | 0°C ~ 70°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 16-SSOP（0.154"，3.90mm 宽） |
| 供应商设备封装： | 16-SSOP |
| 包装： | 管件 |
8
LT1620/LT1621
APPLICATIONS INFORMATION
WU
U
reduces battery charging current until the external load
subsides.
In Figure 4 the LT1620 is coupled with an LT1513 SEPIC
battery charger IC to create an input overcurrent protected
charger circuit.
The programming voltage (VCC – VPROG) is set to 1.0V
through a resistor divider (RP1 and RP2) from the 5V input
supply to ground. In this configuration, if the input current
drawn by the battery charger
combined with the system
load requirements exceeds a current limit threshold of 3A,
the battery charger current will be reduced by the LT1620
such that the total
input supply current is limited to 3A.
Refer to the LT1513 data sheet for additional information.
PROGRAMMING ACCURACY CONSIDERATIONS
PWM Controller Error Amp Maximum Source Current
In a typical battery charger application, the LT1620 con-
trols charge current by servoing the error amplifier output
pin of the associated PWM controller IC. Current mode
control is achieved when the LT1620 sinks all of the
current available from the error amplifier. Since the LT1620
has finite transconductance, the voltage required to gen-
erate its necessary output current translates to input
offset error. The LT1620 is designed for a typical IOUT sink
current of 130
A to help reduce this term. Knowing the
current source capability of the associated PWM control-
ler in a given application will enable adjustment of the
required programming voltage to accommodate the de-
sired charge current. A plot of typical VPROG voltage offset
vs PWM source capability is shown in Figure 5a. For
example, the LTC1435 has a current source capability of
about 75
A. This translates to about –15mV of induced
programming offset at VPROG (the absolute voltage at the
PROG pin must be 15mV lower).
VCC – VPROG Programmed Voltage ≠ 0.8V
The LT1620 sense amplifier circuit has an inherent input
referred 3mV offset when IN+ – IN– = 0V to insure closed-
loop operation during light load conditions. This offset vs
input voltage has a linear characteristic, crossing 0V as
IN+ – IN– = 80mV. The offset is translated to the AVG
output (times a factor of 10), and thus to the programming
voltage VPROG. A plot of typical VPROG offset voltage vs
IN+ – IN– is pictured in Figure 5b. For example, if the
desired load current corresponds to 100mV across the
sense resistor, the typical offset, at VPROG is 7.5mV (the
absolute voltage at the PROG pin must be 7.5mV higher).
This error term should be taken into consideration when
using VID values significantly away from 80mV.
VCC – VPROG2 Programmed Voltage ≠ 1.6V
(LT1620GN Only)
The offset term described above for VPROG also affects the
VPROG2 programming voltage proportionally (times an addi-
tional factor of 2). However, VPROG2 voltage is typically set
well below the zero offset point of 1.6V, so adjustment for this
term is usually required. A plot of typical VPROG2 offset
voltage vs IN+ – IN– is pictured in Figure 5c. For example,
setting the VPROG2 voltage to correspond to IN+ – IN–= 15mV
typically requires an additional –50mV offset (the absolute
voltage at the PROG2 pin must be 50mV lower).
Sense Amplifier Input Common Mode < (VCC – 0.5V)
The LT1620 sense amplifier has additional input offset
tolerance when the inputs are pulled significantly below
the VCC supply. The amplifier can induce additional input
referred offset of up to 11mV when the inputs are at 0V
common-mode. This additional offset term reduces roughly
linearly to zero when VCM is about VCC – 0.5V. In typical
applications, this offset increases the charge current tol-
erance for “cold start” conditions until VBAT moves away
from ground. The resulting output current shift is generally
negative; however, this offset is not precisely controlled.
Precision operation should not be attempted with sense
amplifier common mode inputs below VCC – 0.5V. Input
referred offset tolerance vs VCM is shown in Figure 5d.
VCC ≠ 5V
The LT1620 sense amplifier induces a small additional
offset when VCC moves away from 5V. This offset follows
a linear characteristic and amounts to about
±0.33mV
(input-referred) over the recommended operating range
of VCC, centered at 5V. This offset is translated to the AVG
and AVG2 outputs (times factors of 10 and 20), and thus
to the programming voltages. A plot of programming
offsets vs VCC is shown in Figure 5e.
相关PDF资料 |
PDF描述 |
|---|---|
| 0034.1523 | FUSE 5A 250V 5X20 FAST GLASS |
| 0034.1519 | FUSE 2A 250V 5X20 FAST GLASS |
| LT1621CGN | IC AMP R-R CURRENT SENSE 16-SSOP |
| SSW-130-02-S-S | CONN RCPT .100" 30POS SNGL GOLD |
| 54102-G05-00 | BERGSTRIP 0.100" HEADER |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT1621IGN | 功能描述:IC AMP R-R CURRENT SENSE 16-SSOP RoHS:否 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:73 系列:Over-The-Top® 放大器类型:通用 电路数:4 输出类型:满摆幅 转换速率:0.07 V/µs 增益带宽积:200kHz -3db带宽:- 电流 - 输入偏压:1nA 电压 - 输入偏移:285µV 电流 - 电源:50µA 电流 - 输出 / 通道:25mA 电压 - 电源，单路/双路(±):2 V ~ 44 V，±1 V ~ 22 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:16-WFDFN 裸露焊盘 供应商设备封装:16-DFN-EP（5x3） 包装:管件 |
| LT1621IGN#PBF | 功能描述:IC AMP R-R CURRENT SENSE 16-SSOP RoHS:是 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:73 系列:Over-The-Top® 放大器类型:通用 电路数:4 输出类型:满摆幅 转换速率:0.07 V/µs 增益带宽积:200kHz -3db带宽:- 电流 - 输入偏压:1nA 电压 - 输入偏移:285µV 电流 - 电源:50µA 电流 - 输出 / 通道:25mA 电压 - 电源，单路/双路(±):2 V ~ 44 V，±1 V ~ 22 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:16-WFDFN 裸露焊盘 供应商设备封装:16-DFN-EP（5x3） 包装:管件 |
| LT1621IGN#TR | 功能描述:IC AMP CURR SENSE RR DUAL 16SSOP RoHS:否 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:73 系列:Over-The-Top® 放大器类型:通用 电路数:4 输出类型:满摆幅 转换速率:0.07 V/µs 增益带宽积:200kHz -3db带宽:- 电流 - 输入偏压:1nA 电压 - 输入偏移:285µV 电流 - 电源:50µA 电流 - 输出 / 通道:25mA 电压 - 电源，单路/双路(±):2 V ~ 44 V，±1 V ~ 22 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:16-WFDFN 裸露焊盘 供应商设备封装:16-DFN-EP（5x3） 包装:管件 |
| LT1621IGN#TRPBF | 功能描述:IC AMP R-R CURRENT SENSE 16-SSOP RoHS:是 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:73 系列:Over-The-Top® 放大器类型:通用 电路数:4 输出类型:满摆幅 转换速率:0.07 V/µs 增益带宽积:200kHz -3db带宽:- 电流 - 输入偏压:1nA 电压 - 输入偏移:285µV 电流 - 电源:50µA 电流 - 输出 / 通道:25mA 电压 - 电源，单路/双路(±):2 V ~ 44 V，±1 V ~ 22 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:16-WFDFN 裸露焊盘 供应商设备封装:16-DFN-EP（5x3） 包装:管件 |
| LT1624IS8 | 制造商:Linear Technology 功能描述: |
发布紧急采购，3分钟左右您将得到回复。