参数资料
| 型号： | MAX5969AEVKIT# |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 10/14页 |
| 文件大小： | 0K |
| 描述： | EVAL KIT MAX5969A |
| 标准包装： | 1 |
| 系列： | * |
IEEE 802.3af/at-Compliant, Powered Device Interface
Controllers with Integrated Power MOSFET
Detailed Description
Operating Modes
Depending on the input voltage (V IN = V DD - V SS ), the
MAX5969A/MAX5969B operate in four different modes:
PD detection, PD classification, mark event, and PD
power. The devices enter PD detection mode when the
input voltage is between 1.4V and 10.1V. The device
enters PD classification mode when the input voltage is
between 12.6V and 20V. The device enters PD power
mode once the input voltage exceeds V ON .
Detection Mode (1.4V ≤ V IN ≤ 10.1V)
In detection mode, the PSE applies two voltages on V IN
in the range of 1.4V to 10.1V (1V step minimum) and
then records the current measurements at the two points.
The PSE then computes D V/ D I to ensure the presence
of the 24.9kω signature resistor. Connect the signature
resistor (R DET ) from V DD to DET for proper signature
detection. The MAX5969A/MAX5969B pull DET low in
detection mode. DET goes high impedance when the
input voltage exceeds 12.5V. In detection mode, most of
the MAX5969A/MAX5969B internal circuitry is off and the
offset current is less than 10μA.
If the voltage applied to the PD is reversed, install pro-
tection diodes at the input terminal to prevent internal
damage to the MAX5969A/MAX5969B (see the Typical
Application Circuit ). Since the PSE uses a slope tech-
nique ( D V/ D I) to calculate the signature resistance, the
DC offset due to the protection diodes is subtracted and
does not affect the detection process.
Table 1 . Setting Classification Current
Classification Mode (12.6V ≤ V IN ≤ 20V)
In the classification mode, the PSE classifies the PD
based on the power consumption required by the PD. This
allows the PSE to efficiently manage power distribution.
Class 0 to 5 is defined as shown in Table 1. (The IEEE
802.3af/at standard defines only Class 0 to 4 and Class 5
for any special requirement.) An external resistor (R CLS )
connected from CLS to V SS sets the classification current.
The PSE determines the class of a PD by applying a volt-
age at the PD input and measuring the current sourced
out of the PSE. When the PSE applies a voltage between
12.6V and 20V, the MAX5969A/MAX5969B exhibit a cur-
rent characteristic with a value shown in Table 1. The
PSE uses the classification current information to classify
the power requirement of the PD. The classification cur-
rent includes the current drawn by R CLS and the supply
current of the MAX5969A/MAX5969B so the total current
drawn by the PD is within the IEEE 802.3af/at standard
figures. The classification current is turned off whenever
the device is in power mode.
2-Event Classification and Detection
During 2-event classification, a Type 2 PSE probes PD
for classification twice. In the first classification event,
the PSE presents an input voltage between 12.6V and
20V and the MAX5969A/MAX5969B present the pro-
grammed load I CLASS . The PSE then drops the probing
voltage below the mark event threshold of 10.1V and
the MAX5969A/MAX5969B present the mark current
(I MARK ). This sequence is repeated one more time.
CLASS
MAXIMUM
POWER USED
BY PD
(W)
R CLS
( I )
V IN *
(V)
CLASS CURRENT SEEN AT
V IN (mA)
MIN
MAX
IEEE 802.3af/at PSE
CLASSIFICATION CURRENT
SPECIFICATION (mA)
MIN
MAX
0
1
2
3
4
5
0.44 to 12.95
0.44 to 3.94
3.84 to 6.49
6.49 to 12.95
12.95 to 25.5
> 25.5
619
117
66.5
43.7
30.9
21.3
12.6 to 20
12.6 to 20
12.6 to 20
12.6 to 20
12.6 to 20
12.6 to 20
0
9
17
26
36
52
4
12
20
30
44
64
0
8
16
25
35
—
5
13
21
31
45
—
*V IN is measured across the MAX5969A/MAX5969B input V DD to V SS .
10
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相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX5969AEVKIT# | 功能描述:电源管理IC开发工具 MAX5969A Eval Kit RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V |
| MAX5969BETB+ | 制造商:Maxim Integrated Products 功能描述:- Rail/Tube 制造商:Maxim Integrated Products 功能描述:1-/2-CHANNEL, 2-WIRE SERIAL, 12-BIT ADCS |
| MAX5969BETB+T | 功能描述:热插拔功率分布 802.3at PD Int Controller RoHS:否 制造商:Texas Instruments 产品:Controllers & Switches 电流限制: 电源电压-最大:7 V 电源电压-最小:- 0.3 V 工作温度范围: 功率耗散: 安装风格:SMD/SMT 封装 / 箱体:MSOP-8 封装:Tube |
| MAX5969BETE+T | 功能描述:热插拔功率分布 802.3at PD Int Controller RoHS:否 制造商:Texas Instruments 产品:Controllers & Switches 电流限制: 电源电压-最大:7 V 电源电压-最小:- 0.3 V 工作温度范围: 功率耗散: 安装风格:SMD/SMT 封装 / 箱体:MSOP-8 封装:Tube |
| MAX5969BEVKIT | 功能描述:电源管理IC开发工具 RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V |
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