20-101-1221 Rabbit Semiconductor, 20-101-1221 Datasheet - Page 117

• Manufacturer Part Number: 20-101-1221
• Description: RCM4400W (JAPAN TELEC CERTIFIED)
• Manufacturer: Rabbit Semiconductor
• Series: RabbitCore®r

Specifications of 20-101-1221

• Frequency: 2.4GHz
• Modulation Or Protocol: 802.11 b
• Power - Output: 16dBm
• Voltage - Supply: 3.3V
• Current - Receiving: 450mA
• Current - Transmitting: 450mA
• Data Interface: Connector, 2 x 25 Header
• Memory Size: 512K Flash, 1MB SRAM
• Antenna Connector: SMA
• Operating Temperature: -20°C ~ 85°C
• Package / Case: Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Applications: -
• Sensitivity: -
• Data Rate - Maximum: -
• Other names: 316-1147

C.1 Power Supplies
The RCM4400W requires a regulated 3.3 V DC ±5% power source. The RabbitCore
design presumes that the voltage regulator is on the user board, and that the power is made
available to the RCM4400W board through header J1.
An RCM4400W with no loading at the outputs operating at 58.98 MHz typically draws
80 mA, and may draw up to 450 mA while the Wi-Fi circuit is transmitting or receiving.
C.1.1 Battery-Backup
The RCM4400W does not have a battery, but there is provision for a customer-supplied
battery to back up the data SRAM and keep the internal Rabbit 4000 real-time clock
running.
Header J1, shown in Figure C-1, allows access to the external battery. This header makes
it possible to connect an external 3 V power supply. This allows the SRAM and the inter-
nal Rabbit 4000 real-time clock to retain data with the RCM4400W powered down.
A battery with a nominal voltage of 3 V and a minimum capacity of 165 mA·h is recom-
mended. A lithium battery is strongly recommended because of its nearly constant
nominal voltage over most of its life.
OEM User’s Manual
Appendix C provides information on the current requirements of
the RCM4400W, and includes some background on the chip
select circuit used in power management.
Figure C-1. External Battery Connections
A
PPENDIX
at Header J1
C. P
OWER
S
UPPLY
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