ST 公司的L5961功率管理器件是业界首个用于MOST (Media Oriented Systems Transport)网络的功率管理解决方案。MOST网络允许各种多媒体设备如CD 或 DVD播放器，汽车收音机和个人导航系统增加到汽车内，因此特别适用于汽车多媒体和娱乐系统。L5961 MOST PMD集成了MOST节点所需的所有的电源和功率管理功能，包括MOST固有的功率管理以及专业的诊断和故障，它能为物理层，网络控制器以及MOST节点的外界主控制器提供电源。本文介绍了L5961的主要性能，方框图以及和应用电路。
The L5961 MOST PMD integrates all the discrete circuitry usually necessary to implement power supplies and power management for a MOST node. It includes intrinsic MOST specific power management together with sophisticated diagnostic and fail-safe functions. The MOST PMD is designed to provide direct power supply for the physical layer, the Network Controller and the External Host Controller of a MOST Node.
The L5961 also allows the implementation of a generic MOST node design that can be
reproduced as is in any other project, thus avoiding the activities of redesign and reverification of MOST PMD compliance The L5961 implements complete monitoring of
the supply voltage (over-voltage, under-voltage, critical voltage), moreover it supports multiple power modes like Zeropower-mode (where one complete MOST node sinks around 25μA current) and Ultra-zero power mode (5μA). All the diagnostic protocols from major carmakers are supported and the device reacts to many different wake-up events.
STMicroelectronics Announces Integrated Power-Management Chip for Multimedia Networking in Cars
The ST’s L5961 power management IC is the industry’s first integrated power-management solution for MOST (Media Oriented Systems Transport) networks. Optimized for in car multimedia and infotainment applications, the MOST network was originally developed for the automotive industry, but also has a wide range of applications in many other industries. MOST technology primarily allows for a range of multimedia devices, such as CD or DVD players, car radios, and personal navigation devices, to be added into the car environment with minimal effort.
The new L5961 power management IC, which has been designed in cooperation with fabless semiconductor manufacturer SMSC to work with that company’s MOST network processors, includes both the power supply and MOST-compliant power-management control logic, together with enhanced diagnostic and full system monitoring (power supply, network status, wake-up events, temperature).
A chipset combining the L5961 power-management IC and and SMSC network processor can serve as a building block in any MOST network node, and provides significantly more independence from the individual applications that are connected to the network, in terms of turn-on/off timing and device failure, for example. Additionally, the combined chipset, once validated, can be placed in any MOST application without having to be redesigned and revalidated each time.
The current solution in the industry uses discrete components to implement the power management for MOST network nodes. ST’s integration of both the power-management control logic and power supply within the L5961 therefore provides several key advantages for automotive OEMs, including significant PCB space savings, lower cost, lower cost of ownership and lower stand-by-mode power consumption, helping to meet specifications recently issued by many leading car manufacturers. In particular, the device features multiple power modes, including an Ultra-Zero Power Mode that offers a typical quiescent current of only 5 microamps, a considerably lower value than that achieved with discrete components. The overall offering is a cost- and space-optimized solution that provides considerable advantages in terms of reproducibility and fail-safe behavior of the application.
The L5961 MOST PMD integrates all the discrete circuitry usually necessary to implement power supplies and power management for a MOST node. It includes intrinsic MOST specific power management together with sophisticated diagnostic and fail-safe functions. The MOST PMD is designed to provide direct power supply for the physical layer, the Network Controller and the External Host Controller of a MOST Node.
The L5961 also allows the implementation of a generic MOST node design that can be
reproduced as is in any other project, thus avoiding the activities of redesign and reverification of MOST PMD compliance The L5961 implements complete monitoring of
the supply voltage (over-voltage, under-voltage, critical voltage), moreover it supports multiple power modes like Zeropower-mode (where one complete MOST node sinks around 25μA current) and Ultra-zero power mode (5μA). All the diagnostic protocols from major carmakers are supported and the device reacts to many different wake-up events.
The L5961 is completely configurable through its I2C bus and fully compatible with MOST specifications.
L5961 has been specified in cooperation with SMSC and represents a chipset solution when used with SMSCs MOST network interface controllers (INIC or NIC).
主要特性：
5V or 3.3V / 650mA DC-DC Converter with external sync
5V or 3.3V/ 40mA standby voltage regulator
5V or 3.3V / 60mA switchable voltage regulator
Very low quiescent current (zero power mode and ultra zero power mode feature)
Power management fully compatible to MOST specification
Provides power supply for physical layer and control unit
Switch to power pulse generator
Reacts on four different wake-up events
Switch to power pulse (STPP)
Light ON (for status)
Activity on Diagnostic_I/O
ON/OFF switch
I2C interface
Programmable system configuration
Reset generator
Intrinsic diagnostic transceiver (standard LIN2.0)
3 battery detectors for battery voltage monitoring
Watchdog circuit
PowerSS0-36 and PowerSO-36 packages Options
详细功能：
Provides three basic states:
Zero power mode
All external HW is switched off. PM-chip is switched Off except REG1 voltage
regulator, Switch-to-power-pulse comparator and Control logic.
– Ultra zero power mode
All external HW is switched off. PM-chip is switched Off except ON/OFF Control
logic. PMD can be woken up to reach Zero current mode by activities on
DIAG_I/O line
– Normal
PMD and external HW is powered. One of the four possible wake-up conditions
occurs and the wake-up event is confirmed either by means of PWROFF pin or
I2C bus.
To confirm the on-event:
PWROFF pin must be driven low OR
the right I2C bus command is provided.
Reacts on four different wake-up events
Switch to power pulse (STPP)
Light ON (for status)
Activity on Diag_I/O
ON/OFF switch
I2C interface (allowing system programmability)
Generation of switch to power pulse (STPP)
Online battery monitoring, reacts on battery changes/ events:
Over voltage
Critical voltage
Under voltage
Hardware watchdog triggered with discrete input, available to monitor the activity of the controller
Fail-safe behavior:
Intrinsic filtering time of wake-up events
Protection against software caused failures
Over-temperature warning / thermal protection
Diagnostic transceiver compatible to standard LIN2.0
Block and application diagram example (with INIC)
图1. L5961方框图和应用电路
