ATMEGA169-16MISL709 View Datasheet(PDF) - Atmel Corporation

Part Name

Description

Manufacturer

ATMEGA169-16MISL709

8-bit Microcontroller with 16K Bytes In-System Programmable Flash

Atmel Corporation 

ATmega169 Rev B

All segments connected to a common plane might be dimmed (lower contrast) when

a certain combination of data is displayed.

Problem Fix/Workaround

Default waveform: If there are any unused segment pins, loading one of these with a

1 nF capacitor and always write ‘0’ to this segment eliminates the problem.

Low power waveform: Add a 1 nF capacitor to each common pin.

2. LCD Current Consumption

In an interval where VCC is within the range VLCD -0.2V to VLCD + 0.4V, the LCD

current consumption is up to three times higher than expected. This will only be an

issue in Power-save mode with the LCD running as the LCD current is negligible

compared to the overall power consumption in all other modes of operation.

Problem Fix/Workaround

No known workaround.

1. IDCODE masks data from TDI input

The JTAG instruction IDCODE is not working correctly. Data to succeeding devices

are replaced by all-ones during Update-DR.

Problem Fix / Workaround

– If ATmega169 is the only device in the scan chain, the problem is not visible.

– Select the Device ID Register of the ATmega169 by issuing the IDCODE

instruction or by entering the Test-Logic-Reset state of the TAP controller to

read out the contents of its Device ID Register and possibly data from

succeeding devices of the scan chain. Issue the BYPASS instruction to the

ATmega169 while reading the Device ID Registers of preceding devices of

the boundary scan chain.

– If the Device IDs of all devices in the boundary scan chain must be captured

simultaneously, the ATmega169 must be the fist device in the chain.

• Internal Oscillator Runs at 4 MHz

• LCD Contrast Voltage is not Correct

• External Oscillator is Non-functional

• USART

• ADC Measures with Lower Accuracy than Specified

• Serial Downloading

• IDCODE masks data from TDI input

7. Internal Oscillator Runs at 4 MHz

The Internal Oscillator runs at 4 MHz instead of the specified 8 MHz. Therefore, all

Flash/EEPROM programming times are twice as long as specified. This includes

Chip Erase, Byte programming, Page programming, Fuse programming, Lock bit

programming, EEPROM write from the CPU, and Flash Self-Programming.

For this reason, rev-B samples are shipped with the CKDIV8 Fuse unprogrammed.

Problem Fix/Workaround

If 8 MHz operation is required, apply an external clock (this will be fixed in rev. C).

6. LCD Contrast Voltage is not Correct

The LCD contrast voltage between 1.8V and 3.1V is incorrect. When the VCC is

between 1.8V and 3.1V, the LCD contrast voltage drops approx. 0.5V. The current

consumption in this interval is higher than expected.

18 ATmega169/V

2514KS–AVR–05/04

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