The failure rate (λ) and mean time between failures
(MTBF= 1/ λ) is calculated at max output power and
an operating ambient temperature (T
A
) of +40°C. CUI
Power Modules uses Telcordia SR-332 Issue 2 Method 1 to
calculate the mean steady-state failure rate and standard
deviation (σ).
Telcordia SR-332 Issue 2 also provides techniques to
estimate the upper confidence levels of failure rates based
on the mean and standard deviation.
Mean steady-state failure rate, λ Std. deviation, σ
421 n F ailures/h
60.9 nF ailures/h
the requirements of all applicable safety standards and
regulations for the final product.
Component power supplies for general use should comply
with the requirements in IEC/EN/UL 60950 1
Safety
of Information Technology Equipment.
Product related
standards, e.g. IEEE 802.3af
Power over Ethernet,
and
ETS 300132 2
Power interface at the input to telecom
equipment, operated by direct current (dc)
are based on
IEC/EN/UL 60950 1 with regards to safety.
CUI Power Modules DC/DC converters and DC/DC
regulators are UL 60950 1 recognized and certified in
accordance with EN 60950 1. The flammability rating for
all construction parts of the products meet requirements
for V 0 class material according to IEC 60695 11 10,
Fire
hazard testing, test flames
– 50 W horizontal and vertical
flame test methods.
Isolated DC/DC converters
Galvanic isolation between input and output is verified
in an electric strength test and the isolation voltage
(V
iso
) meets the voltage strength requirement for basic
insulation according to IEC/EN/UL 60950-1.
It is recommended to use a slow blow fuse at the input
of each DC/DC converter. If an input filter is used in the
circuit the fuse should be placed in front of the input filter.
In the rare event of a component problem that imposes a
short circuit on the input source, this fuse will provide the
following functions:
•
Isolate the fault from the input power source so as
not to affect the operation of other parts of
the system
•
Protect the distribution wiring from excessive
current and power loss thus preventing hazardous
overheating
The DC/DC converter output is considered as safety extra
low voltage (SELV) if one of the following conditions is
met:
•
The input source has double or reinforced
insulation from the AC mains according to IEC/EN/
UL 60950-1
•
The input source has basic or supplementary
insulation from the AC mains and the input
of the DC/DC converter is maximum 60
Vdc and connected to protective earth according to
IEC/EN/UL 60950-1
•
The input source has basic or supplementary
insulation from the AC mains and the DC/DC
converter output is connected to protective earth
according to IEC/EN/UL 60950-1
Non - isolated DC/DC regulators
The DC/DC regulator output is SELV if the input source
meets the requirements for SELV circuits according to IEC/
EN/UL 60950-1.
MTBF (mean value) for the NQB series = 2.9 Mh.
MTBF at 90% confidence level = 2.4 Mh
Compatibility with RoHS requirements
The products are compatible with the relevant clauses
and requirements of the RoHS directive 2011/65/EU and
have a maximum concentration value of 0.1% by weight
in homogeneous materials for lead, mercury, hexavalent
chromium, PBB and PBDE and of 0.01% by weight in
homogeneous materials for cadmium.
Exemptions in the RoHS directive utilized in CUI
Power Modules products are found in the Statement of
Compliance document.
Safety Specification
Reliability
CUI Power Modules DC/DC converters and DC/DC
regulators are designed in accordance with the safety
standards IEC 60950 1, EN 60950 1 and UL 60950 1
Safety of Information Technology Equipment.
IEC/EN/UL 60950 1 contains requirements to prevent
injury or damage due to the following hazards:
•
Electrical shock
•
Energy hazards
•
Fire
•
Mechanical and heat hazards
•
Radiation hazards
•
Chemical hazards
On-board DC/DC converters and DC/DC regulators are
defined as component power supplies. As components
they cannot fully comply with the provisions of any
safety requirements without “conditions of acceptability”.
Clearance between conductors and between conductive
parts of the component power supply and conductors on
the board in the final product must meet the applicable
safety requirements. Certain conditions of acceptability
apply for component power supplies with limited stand-off
(see Mechanical Information for further information). It is
the responsibility of the installer to ensure that the final
product housing these components complies with
cui.com
For more information, please visit the
product page.
CUI Inc
│
SERIES:
NQB-D
│
DESCRIPTION:
FULLY REGULATED ADVANCED BUS CONVERTERS
date
11/07/2014
│
page
4 of 36
Absolute Maximum Ratings
parameter
operating temperature (T
P1
)
storage temperature (T
S
)
input voltage (V
I
)
isolation voltage (V
iso
)
input voltage transient (V
tr
)
remote control pin voltage (V
RC
)
SALERT, CTRL, SCL, SDA, SA0,
SA1 (V Logic I/O)
input to output test voltage, see note 1
according to ETSI EN 300 132-2 and Telcordia GR-
1089-CORE
see operating information section
-0.3
-0.3
conditions/description
see thermal consideration section
min
-40
-55
-0.5
typ
max
+125
+125
+80
+65*
2250
+100
+80*
18
3.6
units
°C
°C
V
Vdc
V
V
V
Stress in excess of Absolute Maximum Ratings may cause permanent damage. Absolute Maximum Ratings, sometimes referred to as no destruction limits, are normally tested with one
parameter at a time exceeding the limits of Output data or Electrical Characteristics. If exposed to stress above these limits, function and performance may degrade in an unspecified
manner.
Note
1: Isolation voltage (input/output to base-plate) max 750 Vdc.
* Applies for the narrow input version V
I
= 40-60 V
Fundamental Circuit Diagram
+IN
Driver
+OUT
-OUT
-IN
Auxillary
Supply
Driver
Control
RC
RC isolation
cui.com
For more information, please visit the
product page.
CUI Inc
│
SERIES:
NQB-D
│
DESCRIPTION:
FULLY REGULATED ADVANCED BUS CONVERTERS
date
11/07/2014
│
page
5 of 36
Functional Description
T
P1
, T
P3
= -40 to +90ºC, V
I
= 36 to 75 V, sense pins connected to output pins unless otherwise specified under Conditions.
Typical values given at: T
P1
, T
P3
= +25°C, V
I
= 53 V, max I
O
, unless otherwise specified under Conditions
Configuration File: 190 10-CDA 102 0314/001
parameter
PMBus monitoring accuracy
input voltage (VIN_READ)
output voltage (VOUT_READ)
output current (IOUT_READ)
temperature (TEMP_READ)
fault protection
characteristics
factory default
setpoint accuracy
hysteresis: factory default
hysteresis: configurable via PMBus of threshold
range, note 1
delay
factory default
configurable via PMBus, note 1
fault response time
factory default
configurable via PMBus, note 1
fault response time
setpoint accuracy (I
O
)
IOUT_OC_FAULT_LIMIT factory default
IOUT_OC_FAULT_LIMIT, configurable via PMBus,
note 1
fault response time
OTP_FAULT_LIMIT, factory default
OTP_FAULT_LIMIT, configurable via PMBus, note 1
hysteresis, factory default
hysteresis, configurable via PMBus, note 1
fault response time
-2
0
33
2
300
0
0
200
15.6
200
41
200
-50
0
125
10
300
125
125
16
2
V
%
V
V
μs
V
V
μs
V
V
μs
%
A
A
μs
ºC
ºC
ºC
ºC
μs
V
I
= 53V
V
I
= 53V, 50-100% of max I
O
V
I
= 53V, 10% of max I
O
-2
-1.0
-6
-0.6
-5
±0.2
±0.1
±0.15
±3.5
2
1.0
6
0.6
5
%
%
%
A
ºC
conditions/description
min
typ
max
units
input under voltage lockout
(UVLO)
output voltage - under voltage
protection (VOUT_UV_FAULT_
LIMIT)
output voltage - over voltage
protection (VOUT_OV_FAULT_
LIMIT)
V
OUT
-6
0
16
6
100
over current protection (OCP)
over temperature protection
(OTP)
logic input/output
characteristics
logic input low (V
IL
)
logic input high (V
IH
)
logic output low (V
OL
)
logic output high (V
OH
)
bus free time T(BUF)
Note
CTRL, SA0, SA1, PG, SCL, SDA
CTRL, SA0, SA1, PG, SCL, SDA
CTRL, PG, SALERT, SCL, SDA
I
OL
= 6 mA
CTRL, PG, SALERT, SCL, SDA
I
OH
= -6 mA
note 2
2.7
1.3
2.1
1.1
V
V
0.25
V
V
μs
1: See Operating Information section.
2: PMBus timing parameters according to PMBus spec.
[i=s]This post was last edited by 254262840 on 2015-12-7 13:05[/i] 1. Open the URL [url=https://www.eeworld.com.cn/huodong/201511sample/]https://www.eeworld.com.cn/huodong/201511sample/[/url] and sele...
Cytech’s award-winning live broadcast: Let you learn about ADI’s digital health biosensor series live!Click here to enter the live broadcastLive broadcast time: October 25, 2022 (Tuesday) 10:00-11:30 ...
I recently developed a project to use AM335x to communicate with FPGA. I have debugged it successfully. But I have some questions. I use cs1 to control chip select, but I don't set the base address an...
This week's review highlights:
(1) Newly launched
- phyBOARD-i.MX 8M Plus development board from PHYTEC of Germany
- RTTRenesas high performance CPK-RA6M4 development board, task-based evaluation(2) A...
I am working on a software phase-locked loop for a three-phase power grid (see attached picture), and I have come across some problems. 1) When the input voltage is very low, such as 0.1pu, the SPLL c...
At present, the development of wireless power supply technology for electric vehicles (EVs) is becoming more and more active. In 2012, Volvo of Sweden established Volvo Technology Japan in Tokyo as...[Details]
introduction
With the continuous optimization of surface mount technology (SMT) and the rapid development of chip component manufacturing technology, the application of chip mounters in the el...[Details]
1. Introduction
Automobile pollution is one of the most important issues that people are most concerned about and need to solve urgently. As an important method for detecting automobile exhau...[Details]
Remote keyless entry (RKE) systems have become popular with users, with more than 80% of new cars in North America and more than 70% in Europe equipped with RKE systems. In addition to the obvious ...[Details]
Automotive applications are particularly sensitive to EMI events, which are unavoidable in a noisy electrical environment consisting of a central battery, bundled wiring harnesses, various inductiv...[Details]
In order to highlight the concept of "energy saving and environmental protection" of intelligent buildings, solar street lights are designed for intelligent communities. The inclination and capacit...[Details]
This paper establishes a fuel cell engine test platform based on the NI integrated hardware and software environment. This platform can realize the test and control of fuel cell engines and their a...[Details]
0 Introduction
With the development of society, people pay more and more attention to security work. Monitoring products have been used in various fields instead of being used only in importan...[Details]
Although it is relatively easy to check the stability of a simple amplifier at lower frequencies, it may be much more difficult to evaluate the stability of a more complex circuit. This artic...[Details]
Experimental tasks
A DS18B20 is used to form a temperature measurement system. The temperature measurement accuracy reaches 0.1 degrees. The temperature range is between -20 degrees and +50 de...[Details]
Printed circuit boards ( PCBs
)
are used in most electrical products
. If a PCB has low
insulation resistance
(IR), the performance of the circuits on the PCB will be greatly reduced...[Details]
In 2012, more than half of the cars in the European, Japanese and American car markets will be equipped with color displays, navigation systems, satellite communications and other in-vehicle infota...[Details]
At present, the traffic congestion in cities is quite serious. According to relevant news reports: In China, the traffic congestion has expanded from megacities such as Beijing, Shanghai, and Guangzho...[Details]
1. Overview
At present, an information revolution is in the ascendant around the world, led by microelectronics, computers and communication technologies, and centered on information technolog...[Details]
1 Introduction
With the improvement of people's quality of life, lamps are no longer just basic indoor lighting tools, but also a kind of practical art for architectural decoration. When ther...[Details]