参数资料
型号: MAX978EEE+
厂商: Maxim Integrated Products
文件页数: 9/11页
文件大小: 0K
描述: IC COMPARATOR QUAD 16-QSOP
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 100
类型: 通用
元件数: 4
输出类型: CMOS,满摆幅,TTL
电压 - 电源,单路/双路(±): 2.7 V ~ 5.5 V
电压 - 输入偏移(最小值): 2mV @ 5V
电流 - 输入偏压(最小值): 0.075µA @ 5.5V
电流 - 静态(最大值): 650µA
CMRR, PSRR(标准): 95dB CMRR,100dB PSRR
传输延迟(最大): 28ns
磁滞: 4mV
工作温度: -40°C ~ 85°C
封装/外壳: 16-SSOP(0.154",3.90mm 宽)
安装类型: 表面贴装
包装: 管件
产品目录页面: 1386 (CN2011-ZH PDF)
MAX976/MAX978/MAX998
Single/Dual/Quad, SOT23, Single-Supply,
High-Speed, Low-Power Comparators
_______________________________________________________________________________________
7
2) Choose the hysteresis band required (VHB). For this
example, choose 100mV.
3) Calculate R1. R1 = R3 x (VHB / VCC). Plugging in the
values for this example,
R1 = 1.2M
Ω x (100mV / 5.0V) = 24kΩ
4) Choose the trip point for VIN rising. This is the
threshold voltage at which the comparator switches
from low to high as VIN rises above the trip point. In
this example, choose 3.0V.
5) Calculate R2 as follows:
Choose a standard value for R2 of 16k
Ω.
6) Verify the trip voltage and hysteresis as follows:
IR Receiver
The Typical Operating Circuit shows an application using
the MAX998 as an infrared receiver. The infrared photo-
diode creates a current relative to the amount of infrared
light present. This current creates a voltage across RD.
When this voltage level crosses the voltage applied by the
voltage divider to the inverting input, the output transitions.
Window Comparator
The MAX976 is ideal for making a window detector
(undervoltage/overvoltage detector). The schematic
shown in Figure 3 uses a MAX6120 reference and com-
ponent values selected for a 2.0V undervoltage thresh-
old and a 2.5V overvoltage threshold. Choose different
thresholds by changing the values of R1, R2, and R3.
OUTA provides an active-low undervoltage indication,
and OUTB gives an active-low overvoltage indication.
ANDing the two outputs provides an active-high,
power-good signal. The design procedure is as follows:
1) Select R1. The leakage current into INB- is normally
75nA, so the current through R1 should exceed
1.0A for the thresholds to be accurate. R1 values in
the 50k
Ω to 100kΩ range are typical.
2) Choose the overvoltage threshold (VOTH) when VIN
is rising, and calculate R2 and R3 with the following
formula:
RSUM = R2 + R3 = R1 x [VOTH / (VREF + VH) - 1]
where VH = 1/2VHYST.
3) Choose the undervoltage threshold (VUTH) when VIN
is falling, and calculate R2 with the following formula:
R2 = (R1 + RSUM) x [(VREF - VH) / VUTH] - R1
where VH = 1/2VHYST.
4) Calculate R3 with the following formula:
R3 = (RSUM) - R2
5) Verify the resistor values. The equations are as follows:
VOTH = (VREF + VH) x (R1 + R2 + R3) / R1
VUTH = (VREF - VH) x (R1 + R2 + R3) / (R1 + R2)
V
rising: V
= V
x R1 x
1
R1
V
falling
IN
THR
REF
IN
:
++
=
=
1
2
1
3
1
3
RR
VV
Rx V
R
Hysteresis
V
THF
THR
CC
THR
THF
R2 =
1
V
x R1
1
R1
1
R3
R2 =
1
3.0V
1.2 x 24k
1
24k
1
1.2M
16.2k
THR
REF
=
ΩΩ
Ω
VCC
MAX976
MAX978
MAX998
OUT
0.1
μF
R3
R1
R2
VREF
GND
VIN
VCC
Figure 2. Additional Hysteresis
3
1
3
4
R3
82.1k
Ω
1%
VCC
VIN
R2
24.9k
Ω
1%
R1
100k
Ω
1%
2
6
OVERVOLTAGE
UNDERVOLTAGE
POWER GOOD
1/2
MAX976
MAX6120
1
2
VCC
8
7
5
0.1
μF
1/2
MAX976
Figure 3. Window Comparator
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MAX978EEE+ 功能描述:校验器 IC Quad High Speed Comparator RoHS:否 制造商:STMicroelectronics 产品: 比较器类型: 通道数量: 输出类型:Push-Pull 电源电压-最大:5.5 V 电源电压-最小:1.1 V 补偿电压(最大值):6 mV 电源电流(最大值):1350 nA 响应时间: 最大工作温度:+ 125 C 安装风格:SMD/SMT 封装 / 箱体:SC-70-5 封装:Reel
MAX978EEE+T 功能描述:校验器 IC Quad High Speed Comparator RoHS:否 制造商:STMicroelectronics 产品: 比较器类型: 通道数量: 输出类型:Push-Pull 电源电压-最大:5.5 V 电源电压-最小:1.1 V 补偿电压(最大值):6 mV 电源电流(最大值):1350 nA 响应时间: 最大工作温度:+ 125 C 安装风格:SMD/SMT 封装 / 箱体:SC-70-5 封装:Reel
MAX978EEE+TG068 制造商:Maxim Integrated Products 功能描述:- Rail/Tube
MAX978EEE-T 功能描述:校验器 IC Quad High Speed Comparator RoHS:否 制造商:STMicroelectronics 产品: 比较器类型: 通道数量: 输出类型:Push-Pull 电源电压-最大:5.5 V 电源电压-最小:1.1 V 补偿电压(最大值):6 mV 电源电流(最大值):1350 nA 响应时间: 最大工作温度:+ 125 C 安装风格:SMD/SMT 封装 / 箱体:SC-70-5 封装:Reel
MAX978EEE-TG068 制造商:Maxim Integrated Products 功能描述:DUAL/QUAD HIGH-SPEED LOW-POWER COMPARATORS FO - Tape and Reel