CH706/CH706W
Preliminary - Aug 2021
Page 1 of 79
CH706/CH706W
Isolated Current Sensor IC with Common-Mode Field Rejection
This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice and Cosemitech
assumes no obligation for future manufacture of this product. Contact Cosemitech for the latest status.
Key Features
Package
• Differential Hall sensing rejects common-mode fields
• Reinforced isolation: V
ISO
4800V
RMS
, V
WVRI
605V
RMS
(SOIC16)
V
ISO
3000V
RMS
, V
WVRI
500V
RMS
(SOIC8)
• Single supply: 3.3V or 5V
• Output voltage proportional to AC or DC current
• Low primary conductor resistance: 0.8 mΩ
• Minimized total sensitivity error: ±0.7%
• Wide-bandwidth: 450kHz
• Fast response: 1.2µs
• Integrated shield virtually eliminates capacitive coupling from
current conductor to die
• User-selectable ratiometric behavior of sensitivity, quiescent
voltage, and clamps for simple interface with ADC
• Integrated digital temperature compensation circuitry
• Reference pin can facilitate the follow up design
Applications
• Motor control
• Load detection and management
• Switch-mode power supplies
• Solar Inverter
• Public speaker current sensing
SOIC16 SOIC8
(CH706W) (CH706)
Functional Block Diagram
Dynamic offset
Cansellation
Signal Remodulation
Low Pass
filter
Amp
`
EEPROM
And control logic
Sensitivity Polarity
Offset Trim
Offset TC Trim
VCC
GND
OUT
Sensitivity and
Senstivity TC Trim
Driver
Master Current
Supply
POR
Buffer
Reference
VREF
IP+
IP+
IP-
IP-
IP+
1
2
3
4
8
7
6
5
IP+
IP-
IP-
VCC
OUT
VREF
GND
Ip
C
BYPASS
C
F
C
L
Figure 1: CH706 Function Block
CH706/CH706W
Preliminary - Aug 2021
Page 2 of 79
Dynamic offset
Cansellation
Signal Remodulation
Low Pass
filter
Amp
`
EEPROM
And control logic
Sensitivity Polarity
Offset Trim
Offset TC Trim
VCC
GND
OUT
Sensitivity and
Senstivity TC Trim
Driver
Master Current
Supply
POR
Buffer
Reference
VREF
IP+
IP+
IP-
IP-
IP+
1
2
3
4
8
7
6
5
IP+
IP+
IP+
NC
GND
NC
VREF
Ip
C
BYPASS
C
F
C
L
IP+
IP+
IP-
IP-
5
6
7
8
IP-
IP-
IP-
IP-
OUT
NC
VCC
NC
8
7
6
5
Figure 2: CH706W Function Block