SI1005-C-GM Silicon Laboratories Inc, SI1005-C-GM Datasheet - Page 165

• Manufacturer Part Number: SI1005-C-GM
• Description: IC TXRX MCU + EZRADIOPRO
• Manufacturer: Silicon Laboratories Inc

Specifications of SI1005-C-GM

• Package / Case: 42-QFN
• Frequency: 240MHz ~ 960MHz
• Data Rate - Maximum: 256kbps
• Modulation Or Protocol: FSK, GFSK, OOK
• Applications: General Purpose
• Power - Output: 13dBm
• Sensitivity: -121dBm
• Voltage - Supply: 0.9 V ~ 1.8 V
• Current - Receiving: 18.5mA
• Current - Transmitting: 30mA
• Data Interface: PCB, Surface Mount
• Memory Size: 32kB Flash, 4kB RAM
• Antenna Connector: PCB, Surface Mount
• Number Of Receivers: 1
• Number Of Transmitters: 1
• Wireless Frequency: 240 MHz to 960 MHz
• Interface Type: UART, SMBus, SPI, PCA
• Output Power: 13 dBm
• Operating Supply Voltage: 0.9 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Maximum Supply Current: 4.1 mA
• Minimum Operating Temperature: - 40 C
• Modulation: FSK, GFSK, OOK
• Protocol Supported: C2, SMBus
• Core: 8051
• Program Memory Type: Flash
• Program Memory Size: 32 KB
• Data Ram Size: 4352 B
• Supply Current (max): 4.1 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Operating Temperature: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1875-5

16. On-Chip DC-DC Converter (DC0)
Si1004/5 devices include an on-chip dc-dc converter to allow operation from a single cell battery with a
supply voltage as low as 0.9 V. The dc-dc converter is a switching boost converter with an input voltage
range of 0.9 to 1.8 V and a programmable output voltage range of 1.8 to 3.3 V. The default output voltage
is 1.9 V. The dc-dc converter can supply the system with up to 65 mW of regulated power (or up to
100 mW in some applications) and can be used for powering other devices in the system. This allows the
most flexibility when interfacing to sensors and other analog signals which typically require a higher supply
voltage than a single-cell battery can provide.
Figure 16.1 shows a block diagram of the dc-dc converter. During normal operation in the first half of the
switching cycle, the Duty Cycle Control switch is closed and the Diode Bypass switch is open. Since the
output voltage is higher than the voltage at the DCEN pin, no current flows through the diode and the load
is powered from the output capacitor. During this stage, the DCEN pin is connected to ground through the
Duty Cycle Control switch, generating a positive voltage across the inductor and forcing its current to ramp
up.
In the second half of the switching cycle, the Duty Cycle control switch is opened and the Diode Bypass
switch is closed. This connects DCEN directly to VDD_MCU/DC+ and forces the inductor current to charge
the output capacitor. Once the inductor transfers its stored energy to the output capacitor, the Duty Cycle
Control switch is closed, the Diode Bypass switch is opened, and the cycle repeats.
The dc-dc converter has a built in voltage reference and oscillator, and will automatically limit or turn off the
switching activity in case the peak inductor current rises beyond a safe limit or the output voltage rises
above the programmed target value. This allows the dc-dc converter output to be safely overdriven by a
secondary power source (when available) in order to preserve battery life. The dc-dc converter’s settings
can be modified using SFR registers which provide the ability to change the target output voltage, oscillator
frequency or source, Diode Bypass switch resistance, peak inductor current, and minimum duty cycle.
GND/VBAT-
4.7 uF
0.68 uH
VBAT
DCEN
Figure 16.1. DC-DC Converter Block Diagram
L
Control
Cycle
Duty
parasitic
DC0CN
DC0CF
Bypass
Diode
Rev. 1.0
Control Logic
DC/DC Converter
Reference
Oscillator
Voltage
DC/DC
L
parasitic
Si1000/1/2/3/4/5
GND_MCU/DC-
VDD_MCU/DC+
1uF
I
load
C
load
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