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Important questions you need to think about:

NOTE The power listed above is the peak draw during transmit at 0dBm, or receive, whichever is greater. This will determine battery life in many applications. If the connection/advertising intervals are close to the 4sec/10sec max value, the total power during sleep and during radio rx/tx add up roughly to an even split; for shorter intervals the radio power is much greater.

Important questions you need to think about:

• TI CC254x: old, well known, power efficiency is not great, extremely widely used. power: 27mA@any supply voltage, size: 6x6mm, price: $1.95. NOTE: no DC-DC converter on board.

• nRF51822: newer, excellent, good if a non-realtime MCU is needed, power: 8.0mA@3V, size: 3.5x3.8mm (more commonly 6x6mm), price: $1.92.

• nRF8001: newer, excellent, good if you don't want to develop firmware; essentially same as above

• Broadcom BCM20732: very new, good but support is lame, also good if non-realtime MCU is needed. power: 9.1mA (?), size: 6.5x6.5mm, price: $3.95. NOTE: this is a system in package (SIP), it only needs an external crystal - balun and antenna are on board.

• ST BlueNRG: very new, looks good from datasheet, power: 8.2mA@3V, size: 2.66x2.56mm, price: $1.45.

• Dialog DA14580: very new, looks excellent from datasheet. power: 4.9mA@3V, size: 2.5x2.5mm, price: $1.68. NOTE: this includes a balun on board, still needs crystal and antenna.

• Do you need FCC approval? Do you know how to go about it? (If not, use a module which has approval already)

• Do you know how to tune the RF part of this? That needs special tools (network analyzer, etc) and expertise. When I had to do that, it was a real pain :) (If not, use a module, or use the Broadcom chip which has antenna on board; or Dialog chip which integrates a matching network and has a reference design for antenna)

• Do you want to develop firmware for the Bluetooth SoC? That can be complicated/annoying/expensive. (If not, use nRF8001 or BlueNRG, or use TI CC254x which has ready-made firmwares already)

• What is the primary design driver/goal: size, unit cost, development cost, time-to-market?

• For total size, the Dialog chip is hard to beat.

• For unit cost - I'm not quite sure, depends on your manufacturing capability, but don't ignore the fact that some of these chips need way more support components than others (so that $3 Nordic chip is really more like $5-$6 per unit for the complete subsystem, whereas CC2540 based modules can be had for less than $5). Also don't ignore the $10-$20k (?) for FCC approval amortized over however many units.

• For development cost or time to market - do yourself a favor and use a module :)

• TI CC254x: old, well known, power efficiency is not great, extremely widely used. power: 27mA@any supply voltage, size: 6x6mm, price: $1.95. NOTE: no DC-DC converter on board.

• nRF51822: newer, excellent, good if a non-realtime MCU is needed, power: 8.0mA@3V, size: 3.5x3.8mm (more commonly 6x6mm), price: $1.92.

• nRF8001: newer, excellent, good if you don't want to develop firmware; essentially same as above

• Broadcom BCM20732: very new, good but support is lame, also good if non-realtime MCU is needed. power: 9.1mA (?), size: 6.5x6.5mm, price: $3.95. NOTE: this is a system in package (SIP), it only needs an external crystal - balun and antenna are on board.

• ST BlueNRG: very new, looks good from datasheet, power: 8.2mA@3V, size: 2.66x2.56mm, price: $1.45.

• Dialog DA14580: very new, looks excellent from datasheet, no personal experience yet. power: 4.9mA@3V, size: 2.5x2.5mm, price: $1.68. NOTE: this includes a balun on board, still needs crystal and antenna.

• Do you need FCC approval? Do you know how to go about it? (If not, use a module which has approval already)

• Do you know how to tune the RF part of this? That needs special tools (network analyzer, etc) and expertise. When I had to do that, it was a real pain :) (If not, use a module, or use the Broadcom chip which has antenna on board; or Dialog chip which integrates a matching network and has a reference design for antenna)

• Do you want to develop firmware for the Bluetooth SoC? That can be complicated/annoying/expensive. (If not, use nRF8001 or BlueNRG, or use TI CC254x which has ready-made firmwares already)

• What is the primary design driver/goal: size, power efficiency, unit cost, development cost, time-to-market?

• For total size, the Dialog chip is hard to beat. Don't ignore the size (and keep-out area) needed by your antenna; typical total size is going to be in the 10x10mm range.

• For power efficiency, it kinda depends if your system is transmitting often or not. You probably need to measure it in a realistic scenario, the datasheet is not gonna be much help.

• For unit cost - I'm not quite sure, depends on your manufacturing capability, but don't ignore the fact that some of these chips need way more support components than others (so that $3 Nordic chip is really more like $5-$6 total BOM cost, whereas CC2540 based modules can be had for less than $5). Also don't ignore the $10-$20k (?) for FCC approval amortized over however many units.

• For development cost or time to market - do yourself a favor and use a module :)

• Do you need FCC approval? Do you know how to go about it? (If not, use a module which has approval already)

• Do you know how to tune the RF part of this? That needs special tools (network analyzer, etc) and expertise.  (If not, use a module, or use the Broadcom chip which has antenna on board; or Dialog chip which integrates a matching network and has a reference design for antenna)

• Do you want to develop firmware for the Bluetooth SoC? That can be complicated/annoying/expensive. (If not, use nRF8001 or BlueNRG, or use TI CC254x which has ready-made firmwares already)

• What is the primary design driver/goal: size, unit cost, development cost, time-to-market?

Considering the different possible goals:

For total size, the Dialog chip is hard to beat.

For unit cost - I'm not quite sure, depends on your manufacturing capability, but don't ignore the fact that some of these chips need way more support components than others (so that $3 Nordic chip is really more like $5-$6 per unit for the complete subsystem, whereas CC2540 based modules can be had for less than $5). Also don't ignore the $10-$20k (?) for FCC approval amortized over however many units.

For development cost or time to market - do yourself a favor and use a module :)

• Do you need FCC approval? Do you know how to go about it? (If not, use a module which has approval already)

• Do you know how to tune the RF part of this? That needs special tools (network analyzer, etc) and expertise. When I had to do that, it was a real pain :) (If not, use a module, or use the Broadcom chip which has antenna on board; or Dialog chip which integrates a matching network and has a reference design for antenna)

• Do you want to develop firmware for the Bluetooth SoC? That can be complicated/annoying/expensive. (If not, use nRF8001 or BlueNRG, or use TI CC254x which has ready-made firmwares already)

• What is the primary design driver/goal: size, unit cost, development cost, time-to-market?

Considering the different possible goals:

• For total size, the Dialog chip is hard to beat.

• For unit cost - I'm not quite sure, depends on your manufacturing capability, but don't ignore the fact that some of these chips need way more support components than others (so that $3 Nordic chip is really more like $5-$6 per unit for the complete subsystem, whereas CC2540 based modules can be had for less than $5). Also don't ignore the $10-$20k (?) for FCC approval amortized over however many units.

• For development cost or time to market - do yourself a favor and use a module :)