MC33341 Motorola, MC33341 Datasheet - Page 11

• Manufacturer Part Number: MC33341
• Description: POWER SUPPLY BATTERY CHARGER REGULATION CONTROL CIRCUIT
• Manufacturer: Motorola

The above figure shows the MC33341 configured for load high–side current sensing allowing common paths for both power
and ground, between the source and load. The Differential Amplifier inputs, Pins 1 and 6, are used to sense the load induced
voltage drop that appears across resistor R S . The internal voltage and current regulation thresholds are selected by the
respective external connections of Pins 2 and 6. Resistor R3 is required in applications where high peak levels of load current
are possible from the battery or load bypass capacitor. The resistor value should be chosen to limit the input current of the
internal V CC clamp diode to less than 20 mA. Excessively large values for R3 ill degrade the current sensing accuracy.
MOTOROLA ANALOG IC DEVICE DATA
Source
Source
Return
Isolator
Opto
V reg
+
+
V
1.2 R2
th(V)
R1
R2
R1
)
)
1
1
1.2 V
Figure 17. Load High–Side Current Sensing with
Internally Fixed Current and Voltage Thresholds
8
1
R
R
R
Differential Amp
Disable Logic
Differential Amp
Inverting Amp
R
R
R
V CC
V CC
0.4 V
7
2
MC33341
I reg
V CC
V CC
+
+
1.2 V
V sen
I sen
V
0.2
R
V th
I th
th(I HS)
S
0.2 V
R
V CC
S
V
6
I
3
V CC
Transconductance
V CC
Comp
0.2 V 0.4 V 1.2 V
Amp
Reference
R3
V CC
V CC
5
4
R2
R3
+
I
pk
R1
R
0.02
S
– 0.6
Load
Load
R S
Battery or
Resistive
Load
11