C8051F541-IM Silicon Laboratories Inc, C8051F541-IM Datasheet - Page 130

• Manufacturer Part Number: C8051F541-IM
• Description: IC 8051 MCU 16K FLASH 32-QFN
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F54xr

Specifications of C8051F541-IM

• Program Memory Type: FLASH
• Program Memory Size: 16KB (16K x 8)
• Package / Case: 32-QFN
• Mfg Application Notes: LIN Bootloader AppNote
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 50MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 25
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.25 V
• Data Converters: A/D 25x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Processor Series: C8051F5x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Maximum Clock Frequency: 50 MHz
• Number Of Programmable I/os: 25
• Operating Supply Voltage: 1.8 V to 5.25 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: C8051F540DK
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 336-1672 - BOARD PROTOTYPE W/C8051F540336-1669 - KIT DEVELOPMENT FOR C8051F540
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1673-5

C8051F54x
16.1. Power-On Reset
During power-up, the device is held in a reset state and the RST pin is driven low until V
V
increases (V
power-on and V
On exit from a power-on reset, the PORSF flag (RSTSRC.1) is set by hardware to logic 1. When PORSF is
set, all of the other reset flags in the RSTSRC Register are indeterminate (PORSF is cleared by all other
resets). Since all resets cause program execution to begin at the same location (0x0000) software can
read the PORSF flag to determine if a power-up was the cause of reset. The content of internal data mem-
ory should be assumed to be undefined after a power-on reset. The V
power-on reset.
16.2. Power-Fail Reset/V
When a power-down transition or power irregularity causes V
monitor will drive the RST pin low and hold the CIP-51 in a reset state (see Figure 16.2). When V
to a level above V
memory contents are not altered by the power-fail reset, it is impossible to determine if V
the level required for data retention. If the PORSF flag reads 1, the data may no longer be valid. The V
monitor is enabled after power-on resets. Its defined state (enabled/disabled) is not altered by any other
reset source. For example, if the V
V
monitor must be enabled to the higher setting (VDMLVL = 1) and selected as a reset source if soft-
ware contains routines which erase or write Flash memory. If the V
set to the high level, any erase or write performed on Flash memory will cause a Flash Error device
reset.
130
RST
DD
. A delay occurs before the device is released from reset; the delay decreases as the V
monitor will still be disabled after the reset. To protect the integrity of Flash contents, the V
DD
DD
ramp time is defined as how fast V
Logic HIGH
Logic LOW
RST
monitor reset timing.
2.70
2.55
2.0
1.0
, the CIP-51 will be released from the reset state. Note that even though internal data
Figure 16.2. Power-On and V
/RST
DD
V
RST
DD
Monitor
monitor is disabled by code and a software reset is performed, the
Power-On
Reset
T
PORDelay
Rev. 1.1
DD
DD
ramps from 0 V to V
Monitor Reset Timing
DD
to drop below V
Monitor
Reset
VDD
DD
DD
monitor is enabled following a
monitor is not enabled and
RST
). Figure 16.2. plots the
RST
VDD
, the power supply
DD
DD
t
dropped below
settles above
DD
ramp time
DD
returns
DD
DD