The CG208 is a fully integrated digital two-channel current regulator. Each channel comprises of a digital regulator, low-side power switch, a freewheeling diode and a shunt resistor. A complete current regulator can be established with a minimum number of external components.
The load current is sensed by the internal shunt and the voltage drop is digitized by an integrated A/D converter.
The power stage is switched with constant frequency and variable duty cycle. The load current is sensed entirely in both switch phases.
A digital current regulation circuitry compares the actual shunt current with the target current value and controls the duty cycle of the low-side power switch with a programmable cycle frequency. Also the settling- and regulation time constants are set via SPI interface. This allows the software to adopt the regulator characteristics to changing ambient conditions.
A diagnosis circuitry in each channel reports error conditions via SPI register. Additionally a digital error output as direct output pin reports the occurrence of an error. Alternatively each channel can operate as a processor controlled power switch bypassing the internal current regulator.
|
Customer benefits:
- No end of assembly line adjustment necessary
- Regulator with minimum number of external components required
- Hardware synergies by multi-channel application (synchronization)
- No need for µC real time computing power for current regulators
- Frequency controlled valves for best EMC performance
- High safety level due to the sophisticated diagnosis features and µC fail safe action
- Power stage temperature under control
- High quality, high robustness design & package
|
|
CG208 features:
- High precision regulation ±1% at 1.2 A, 25°C
- High precision over entire temperature range
- TQFP_epad: -40°C≤TJ ≤ 150°C
- Bare die: -40°C≤TJ ≤ 175°C
- High current resolution (∆ = 0.6 mA) over the current regulation range from 0.6mA to 1228mA
- Wide battery voltage range from 6.3V to 43V
- Daisy chain frequency synchronization
- Software adjustable a) power stage cycle frequency b) integrator control time c) regulator step response and fast settling features
- Fully programmable sinusoidal dither function
- Current measurement can be accessed via SPI and via analog values
- Self protected power stage via over current limiter and additional over current/temperature shut down
- Extra PIN for report error status interrupt action and various diagnostics via fast 4 MHz SPI
- 3V/5V compatible digital I/O pins
- Optional use as processor controlled power switch
- Package: TQFP44_epad & bare die
|