參數(shù)資料
型號(hào): MAX987ESA
廠商: MAXIM INTEGRATED PRODUCTS INC
元件分類: 運(yùn)動(dòng)控制電子
英文描述: High-Speed, Micropower, Low-Voltage, SOT23, Rail-to-Rail I/O Comparators
中文描述: COMPARATOR, 7000 uV OFFSET-MAX, 210 ns RESPONSE TIME, PDSO8
封裝: 0.150 INCH, SOIC-8
文件頁數(shù): 9/12頁
文件大小: 141K
代理商: MAX987ESA
M
High-S peed, Mic ropower, Low-Voltage,
S OT 23, Rail-to-Rail I/O Comparators
_______________________________________________________________________________________
9
5) Calculate R2 as shown. For this example, choose an
8.2k
standard value:
1
V
V
1
3.0V
1.2 x 12k
12
6) Verify trip voltages and hysteresis as follows:
MAX988/MAX992/MAX996
The MAX988/MAX992/MAX996 have ±2.5mV internal
hysteresis. They have open-drain outputs and require
an external pull-up resistor (Figure 2). Additional hys-
teresis can be generated using positive feedback, but
the formulas differ slightly from those of the
MAX987/MAX991/MAX995.
Use the following procedure to calculate resistor
values:
1) Select R3 according to the formulas R3 = V
REF
/ 1μA
or R3 = (V
REF
- V
CC
) / 1μA - R4. Use the smaller of
the two resulting resistor values.
2) Choose the hysteresis band required (V
HB
). For this
example, choose 50mV.
3) Calculate R1 according to the following equation:
R1 = (R3 + R4) x (V
HB
/ V
CC
)
4) Choose the trip point for V
IN
rising (V
THR
; V
THF
is
the trip point for V
IN
falling). This is the threshold
voltage at which the comparator switches its output
from low to high as V
IN
rises above the trip point.
5) Calculate R2 as follows:
6) Verify trip voltages and hysteresis as follows:
Circ uit Layout and Bypassing
These comparators’ high-gain bandwidth requires
design precautions to maximize their high-speed capa-
bility. The recommended precautions are:
1) Use a printed circuit board with an unbroken, low-
inductance ground plane.
2) Place a decoupling capacitor (a 0.1μF ceramic
capacitor is a good choice) as close to V
CC
as
possible.
3) On the inputs and outputs, keep lead lengths short
to avoid unwanted parasitic feedback around the
comparators.
4) Solder the devices directly to the printed circuit
board instead of using a socket.
V rising: V
= V
x R1 x
1
R1
V falling
THR
REF
1
2
R
+
+
+
:
+
3
=
=
1
3
4
1
4
R
R
V
V
R
R
x V
R
Hysteresis
V
V
THF
THR
CC
THR
THF
R2 =
1
V
V
THR
REF
+
x R
R
R
R
1
1
1
1
3
4
V rising: V
= V
x R1 x
1
R1
V falling
THR
REF
+
+
:
1
R
=
=
1
2
R
1
3
R
3
V
V
x V
R
Hysteresis
V
V
THF
THR
CC
THR
THF
R2 =
R2 =
THR
REF
.
8 03
x R
R
R
k
M
k
1
1
1
1
3
1
1
2 2
=
V
EE
V
CC
OUT
R3
R2
R1
R4
0.1
μ
F
V
REF
V
IN
V
CC
MAX988
MAX992
MAX996
Figure 2. Additional Hysteresis (MAX988/MAX992/MAX996)
相關(guān)PDF資料
PDF描述
MAX987EUK-T High-Speed, Micropower, Low-Voltage, SOT23, Rail-to-Rail I/O Comparators
MAX988 High-Speed, Micropower, Low-Voltage, SOT23, Rail-to-Rail I/O Comparators
MAX988ESA High-Speed, Micropower, Low-Voltage, SOT23, Rail-to-Rail I/O Comparators
MAX988EUK-T High-Speed, Micropower, Low-Voltage, SOT23, Rail-to-Rail I/O Comparators
MAX995ESD High-Speed, Micropower, Low-Voltage, SOT23, Rail-to-Rail I/O Comparators
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX987ESA+ 功能描述:校驗(yàn)器 IC Single uPower Comparator RoHS:否 制造商:STMicroelectronics 產(chǎn)品: 比較器類型: 通道數(shù)量: 輸出類型:Push-Pull 電源電壓-最大:5.5 V 電源電壓-最小:1.1 V 補(bǔ)償電壓(最大值):6 mV 電源電流(最大值):1350 nA 響應(yīng)時(shí)間: 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SC-70-5 封裝:Reel
MAX987ESA+T 功能描述:校驗(yàn)器 IC Single uPower Comparator RoHS:否 制造商:STMicroelectronics 產(chǎn)品: 比較器類型: 通道數(shù)量: 輸出類型:Push-Pull 電源電壓-最大:5.5 V 電源電壓-最小:1.1 V 補(bǔ)償電壓(最大值):6 mV 電源電流(最大值):1350 nA 響應(yīng)時(shí)間: 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SC-70-5 封裝:Reel
MAX987ESA-T 功能描述:校驗(yàn)器 IC Single uPower Comparator RoHS:否 制造商:STMicroelectronics 產(chǎn)品: 比較器類型: 通道數(shù)量: 輸出類型:Push-Pull 電源電壓-最大:5.5 V 電源電壓-最小:1.1 V 補(bǔ)償電壓(最大值):6 mV 電源電流(最大值):1350 nA 響應(yīng)時(shí)間: 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SC-70-5 封裝:Reel
MAX987EUK 制造商:Maxim Integrated Products 功能描述:5 PIN COUNT SOT PACKAGE TYPE - Bulk
MAX987EUK+ 制造商:Maxim Integrated Products 功能描述:COMPARATOR SGL R-R I/O 2.75V/5.5V 5PIN SOT-23 - Bulk 制造商:Maxim Integrated Products 功能描述:MAX987 rail-to-rail comparator, SOT23-5