SI9161BQ-T1 Vishay, SI9161BQ-T1 Datasheet - Page 8

• Manufacturer Part Number: SI9161BQ-T1
• Description: IC, VOLTAGE MODE PWM CTRL, 6V, TSSOP-16
• Manufacturer: Vishay

Specifications of SI9161BQ-T1

• Input Voltage: 6V
• Output Voltage: 5.2V
• Output Current: 10mA
• Frequency: 2MHz
• Power Dissipation Pd: 925mW
• Supply Voltage Range: 2.7V To 6V
• Digital Ic Case Style: TSSOP
• No. Of Pins: 16
• Mounting Style: SMD/SMT
• Package / Case: TSSOP-16
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Si9161
Vishay Siliconix
OPERATION OF THE Si9161 BOOST CONVERTER
The Si9161 combined with optimized complementary
MOSFETs provides the ideal solution to small, high efficiency,
synchronous boost power conversion. Optimized for a 1-cell
lithium ion, or 3-cell to 4-cell Nickel metal hydride battery, it is
capable of switching at frequencies of up to 2 MHz. Combined
with the Si6801, a complimentary high-frequency MOSFET,
efficiencies of over 90% are easily achieved in a very small
area; with light-load mode, efficiency over 80% can be
achieved at power less than 1/2 W.
PWM Controller
The Si9161 implements a user-selectable synchronous/non-
synchronous voltage mode PWM control topology and is
especially designed for battery power conversion. Voltage-
mode control results in the most efficient power conversion
solution. Figure 1 below illustrates a schematic for a
synchronous boost converter with an input range of 2.7 V to
S-60752—Rev. B, 05-Apr-99
8
FIGURE 1. Si9161 Boost Converter
5 V which covers the range of 1-cell LiIon and 3-cell or 4-cell
NiMH/NiCd battery input respectively, and an output voltage of
5 V. Note the maximum input voltage is limited to the output
voltage for a boost converter.
The switching frequency is determined by an external
capacitor and resistor connected to C
graph on page 5 in the Typical Characteristics section shows
the typical C
frequency. Si9161 oscillator frequency can be easily
synchronized to external frequency as long as external
switching frequency is higher than the internal oscillator
frequency. The synchronization circuit is a series resistor and
capacitor fed into the C
synchronization pulse should be greater than 1.5 V in
amplitude and a near square wave pulsed clock. Figure 1
shows typical values for the synchronization components.
osc
and R
osc
FaxBack 408-970-5600, request 70747
osc
values for various switching
pin of the Si9161. The
osc
and R
www.siliconix.com
osc
pins. The