System Energy Manager


The system energy manager is a highly integrated microcontroller that provides several key features for systems including key scanning and control, battery and power management, as well as two 2-Wire serial I/O Ports. It incorporates the Dallas 8051-compatible high-speed microcontroller core which has been redesigned to eliminate wasted clock and memory cycles. Every standard 8051 instruction is executed between 1.5 and 3 times faster than the original for the same crystal speed. Looking at it another way, the high-speed core achieves the same throughput as a standard 8051 while using much less power as a result of fewer required clock cycles. As a result, the firmware can easily support many tasks required by mobile systems within a single component.

The controller is designed to off-load battery and power management tasks from the host CPU and thereby make possible an efficient solution for systems. In addition to the microcontroller core, it incorporates an 8-channel, 10-bit A/D converter with external reference so that its firmware can perform battery management tasks without burdening the host CPU. A four-channel 8-bit pulse-width modulator allows digital control of functions such as LCD contrast and brightness. An 8-bit port is provided for key scan inputs. A total of 88 parallel I/O pins are available for key scanning, system configuration, and power management control.

The system energy manager scans a key matrix and interfaces to the host CPU via an 8042-compatible port. The benefits of sophisticated power management and permanently powered functions are thereby attained without adding to the system's chip count.

Two 2-wire, bi-directional serial buses are incorporated to facilitate the management of slave peripheral devices on the motherboard, such as digital temperature sensors and potentiometers, and to support external low-speed I/O devices such as monitor configuration channels, pen tablets, and joysticks.

Because a direct interface to the X-bus is provided, the controller is not dependent on a particular core logic chip or chip set. Independent chip select inputs for the keyboard controller, power management #1, and power management #2 registers are provided.
DS80CH11: Pin Assignment DS80CH11: Pin Assignment Enlarge+

Key Features

  • High speed 80C32 compatible core:
    • High performance 4 clocks/machine cycles (8032 = 12)
    • Low Power: typically 1/3 power for equivalent 8032 throughput
    • Maximum clock speed up to 25MHz at 5.0V
    • Ultra-low stop mode power (typ. 1uA) "IDLE" mode (typ. 10mA)
    • Multiple wake-up sources from STOP including key scan, 2-wire, host I/F, or external interrupt
    • Three 16-bit timers, 1 serial port
    • 256-byte scratchpad
    • 256 bytes MOVX RAM
  • Keyboard Control:
    • Replaces 8042 and key scan microcontroller
    • 2 Parallel I/O ports for key scan outputs
    • One interrupt-driven 8-bit input port to initiate key-scan sequence
  • Input/Output:
    • Total of eleven 8-bit I/O ports; all pins can individually programmed to serve as general purpose digital input/output.
    • 8-bit port supports one or more special functions:
      • Port 0, 2, 3: external program/data memory interface
      • Port 1, 3: UART, 2-Wire serial, timers, external interrupt I/O.
      • Port 4, 8, 9: Key scan input/output
      • Port 5: A/D inputs
      • Port 6: PWM Outputs
      • Port 7: activity monitor, LED control
      • Port 10: GPIO
  • Analog input/output:
    • Eight-channel, 10-bit A/D with power down mode supports charging NiMH rechargeable cells
    • 4-channel, 8-bit PWM supports LCD brightness and contrast control
  • 2-Wire bi-directional serial buses
    • Master/slave multi-drop operation
    • Manages on-board slaves or external I/O devices
  • Power Control
    • Generates system power on reset
    • Programmable power down pin states
Part Number MCU Core Core Clock Speed
Data Processing Internal SRAM
USARTs Timer Features
DS80CH11  8051 (CISC) 25 8-bit 0.25 1 Watchdog
See All Microcontrollers (42)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Technical Documents

App Note 4427 Demonstrating Green Technology with Apples, Oranges, Lemons, and Limes

Quality and Environmental Data

Product Reliability Reports: DS80CH11.pdf 
Lead-Free Package Tin (Sn) Whisker Reports

Related Resources